# 2017 Heat soak hesitation / WOT miss shift



## Morsel (May 11, 2021)

The first thing you should try whenever you have a performance issue with the engine (hesitation in the heat in your case) is to refuel at a different top tier gas station (Exxon, Shell, full list here TOP TIER™ Gasoline Brands). Gas stations occasionally get bad batches. 

Your old Ford 300 with 8:1 compression wont care, but these modern engines do.

The transmission behavior is probably the result of the shop overfilling it.

Have the dealership, not some random shop, check the fluid level.
It has to be checked at a specific temperature. If it is not, you can easily overfill it.
Overfilling the transmission as little as half a quart can cause those exact problems.


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## 6Speed2016LT (Jun 14, 2016)

Definitely second the top tier premium gas.......Until I knew better I was running regular 87 Octane gas for the first few years....When I switched to Premium 91+ it was an entirely different car. Especially when hot outside.

Jason


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## jblackburn (Apr 14, 2012)

Mine does the heat soak thing in heavy traffic for sure. It is 49593883x more apparent when run on low octane.


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## Morsel (May 11, 2021)

Yes, your cars pull timing in response to higher IATs.










If you have another issue thats causing the car to pull even more timing (knock from low quality gas, carbon, etc), you're *really *gonna notice it.

That's why its important to always check the basics like fuel quality or spark plugs before blaming something mechanical.

Below are some examples of IAT spark correction tables.
These tell the ECM how much advance to add or remove from the final spark advance based on intake air temperature (x axis) and cylinder airmass (basically engine load, on the y axis)
Granted the amount of timing added or pulled according to this table isnt 1:1 - it modulates the values based on engine rpm, humidity, coolant temperature, etc so that its not totally falling on its face in severe operating conditions, but it can still pull quite a bit of timing if everything lines up.

Stock 2011 1.4 cruze:










2010 6.2 camaro:









Its fascinating to see how conservative GM is with these settings.
Granted their higher performance cars (z06 for example) are far more aggressive,
but they start pulling timing on my camaro at 86 degrees Fahrenheit.

Meanwhile Dodge, for example, makes absolutely no changes to spark unless IATs are very high.


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## Cobawlt2010 (May 13, 2021)

Morsel said:


> The first thing you should try whenever you have a performance issue with the engine (hesitation in the heat in your case) is to refuel at a different top tier gas station (Exxon, Shell, full list here TOP TIER™ Gasoline Brands). Gas stations occasionally get bad batches.
> 
> Your old Ford 300 with 8:1 compression wont care, but these modern engines do.
> 
> ...


1. I always fill up with CITGO, Costco, or Shell. It's usually CITGO though since it's so close to work. Usually 87 or 89. I was told by the dealership there's little point putting premium in it.

2. Trans service was done at a dealership.

The heat soak thing is push on the gas. Get no response until 2-3 seconds after I am on the gas pedal.

I'm not sure what is up with both issues to be honest.


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## jblackburn (Apr 14, 2012)

> 1. I always fill up with CITGO, Costco, or Shell. It's usually CITGO though since it's so close to work. Usually 87 or 89. I was told by the dealership there's little point putting premium in it.


They tell you that to sell you an economy car. No one wants to buy one that needs something more than 87. The Buick/Cadillac dealer down the road may have customers that would be more accepting of it.

The reality is they benefit greatly from 91+ octane. It's a turbo motor, and turbo motors heat soak and pull the crap out of timing and feel severely down on power to avoid knock.

91+ will also help you avoid piston-cracking LSPI which is quite common in 2017s.


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## Thebigzeus (Dec 2, 2018)

Dealerships sadly aren’t experts on cars.


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## JLL (Sep 12, 2017)

Thebigzeus said:


> Dealerships sadly aren’t experts on cars.


It all depends on the technicians. Some are ALOT smarter than others.


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## Morsel (May 11, 2021)

Cobawlt2010 said:


> 1. I always fill up with CITGO, Costco, or Shell. It's usually CITGO though since it's so close to work. Usually 87 or 89. I was told by the dealership there's little point putting premium in it.
> 
> 2. Trans service was done at a dealership.
> 
> ...


Disconnect the battery, wait 3 minutes, and then reconnect the battery.
If its still being dumb, go back to the dealership and tell them you're still experiencing shifting problems.


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## Cobawlt2010 (May 13, 2021)

jblackburn said:


> They tell you that to sell you an economy car. No one wants to buy one that needs something more than 87. The Buick/Cadillac dealer down the road may have customers that would be more accepting of it.
> 
> The reality is they benefit greatly from 91+ octane. It's a turbo motor, and turbo motors heat soak and pull the crap out of timing and feel severely down on power to avoid knock.
> 
> 91+ will also help you avoid piston-cracking LSPI which is quite common in 2017s.


This was brought up to a technician, not to sales staff. He said 87 is fine. He seemed knowledgeable and he said he was with the dealership for over 30 years. We were on a test drive because of a squeak in certain conditions (something I haven't figured out either but am not super worried about). That happens at high load with low RPM and was worried about LSPI. I do my own oil changes with 5w30 Mobile 1 EP 15k oil (though I think they're now marketing it as 20k oil). I go by the service indicator and change my oil then. I've often thought about using Lucas but considering it isn't Dexos 2 certified I'd rather not. I know it's mostly down to the $$$ for the certification but I'd rather be in spec should something go wrong... though I guess my warranty is up so I shouldn't really care anymore. Either way, I'm fitting the bill at this point.

I have tried high octane and the squeak has not gone away and I noticed no measurable difference in performance of the vehicle.


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## Cobawlt2010 (May 13, 2021)

Morsel said:


> Disconnect the battery, wait 3 minutes, and then reconnect the battery.
> If its still being dumb, go back to the dealership and tell them you're still experiencing shifting problems.


Was actually planning on doing that this weekend as well as lifting it and checking for fluid leaks...


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## Morsel (May 11, 2021)

jblackburn said:


> They tell you that to sell you an economy car. No one wants to buy one that needs something more than 87. The Buick/Cadillac dealer down the road may have customers that would be more accepting of it.
> 
> The reality is they benefit greatly from 91+ octane. It's a turbo motor, and turbo motors heat soak and pull the crap out of timing and feel severely down on power to avoid knock.
> 
> 91+ will also help you avoid piston-cracking LSPI which is quite common in 2017s.


He does not need to rum premium fuel.
Theres more involved to Low speed preignition than just octane rating


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## Morsel (May 11, 2021)

Cobawlt2010 said:


> This was brought up to a technician, not to sales staff. He said 87 is fine. He seemed knowledgeable and he said he was with the dealership for over 30 years. We were on a test drive because of a squeak in certain conditions (something I haven't figured out either but am not super worried about). That happens at high load with low RPM and was worried about LSPI. I do my own oil changes with 5w30 Mobile 1 EP 15k oil (though I think they're now marketing it as 20k oil). I go by the service indicator and change my oil then. I've often thought about using Lucas but considering it isn't Dexos 2 certified I'd rather not. I know it's mostly down to the $$$ for the certification but I'd rather be in spec should something go wrong... though I guess my warranty is up so I shouldn't really care anymore. Either way, I'm fitting the bill at this point.


Don't use Lucas oil. Continue using the recommended oil, change it when the car tells you to.

GM has active measures to try and avoid "come backs" - they really do want to try and fix whatever problem you're having. If you bring it into the dealer and tell them you're still experiencing shifting issues, they should be giving you a rental and taking however long they need to figure out what's going on.

Here, in a forum where we haven't even seen your car, let alone logged what it was doing, there's not much constructive advice we can give aside from letting you know common problems that cause similar symptoms to what you're experiencing, or maybe some other advise that could help later down the road.

So lets go on a tangent about LSPI! 🙃 

You're not hearing knock.
Light spark knock sounds like a can rattling in your cupholder. Its so faint and generic sounding it can be confused with just about anything.
If you look up spark knock on youtube, 90% of the videos are just that.
It is of no concern.

Heavy knock sounds horrible - like this but louder:





But you will never hear this unless you filled up with some ridiculously poor quality fuel or some idiot tuner suppressed GM's knock mitigation strategies.
Your car's knock sensors are set to just about the most sensitive they can realistically be:









In contrast to the previous generation 1.4, where you actually hear light knock at low RPMs:
(raising boost too low without changing these sensitivities is what cracks ringlands on those engines)









Now LSPI (or "super knock", yes researchers really call it that) is a special catastrophic mode of knock that small displacement, direct injected, turbocharged engines are susceptible to. Unlike conventional knock, which is extremely well studied and managed, LSPI occurs randomly following a minor knock event, occurs at a point in the process where the ECM cannot respond to it, and conventional means of suppressing knock (pulling timing and adding fuel) actually make it worse.

This is a graph show the devastating spike in cylinder pressures when LSPI (super knock) occurs:









Current research in preventing its occurrence all come down to combustion chamber design.
The way manufacturers band-aid the problem is to simply not load the engine at low RPMs (you car limits power quite a bit below 3000rpm), and then try to minimize knock as much as possible.
You may have seen oils with a "helps prevent low speed preignition" label on them. Modern oils have been reformulated to help keep blowby from triggering knock events.

This figure explains how particulates present in blow-by gasses and carbon can trigger LSPI:








Before someone says something about catch cans - that wont help you either.

GM now has a turbo 3 cylinder in the new trailblazers that is pretty darn quick, and is rated to pull 1000lbs.
They're figuring out ways around it.

But because you're engine is not their latest design, the best you can do is follow GM's service recommendations, and maybe ask to see if a software update is available.

If the car feels like its starting to cost more than its worth, see how much you can get for a trade-in.


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## jblackburn (Apr 14, 2012)

Morsel said:


> He does not need to rum premium fuel.
> Theres more involved to Low speed preignition than just octane rating


Yes, largely oil too.

The fact remains that power delivery is a lumpy, inconsistent, jittery mess on both Gen 1 and 2 1.4Ts on 87 octane. It is terrible in 70F weather, and it is way worse in 95F weather. Other manufacturers tune better to run on 87, but GM is not one of them.


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## 6Speed2016LT (Jun 14, 2016)

91+ Octane and Amsoil, Thank us all later...


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## Morsel (May 11, 2021)

jblackburn said:


> Yes, largely oil too.
> 
> The fact remains that power delivery is a lumpy, inconsistent, jittery mess on both Gen 1 and 2 1.4Ts on 87 octane. It is terrible in 70F weather, and it is way worse in 95F weather. Other manufacturers tune better to run on 87, but GM is not one of them.


Look, these cars are slow. That's just the way they are. There is nothing wrong with that, but if you're expecting Type R or WRX performance out of this thing, you're gonna be disappointed. Tuning can address quite a bit of the drivability complaints (especially with the older cruzes), but you're not gonna catch up with other sportier cars.

Not trying to talk trash, but its important that we're all on the same page in terms of what is realistically achievable out of this car.

I don't get into my cruze and expect it to respond like my ls3, or the 5.7 I built for a friend's charger PPV.

Having said that:

Yes, I've logged enough of these things to know the engine prefers higher octane fuel. The ECM runs pretty much entirely on knock feedback on 87 octane.

However you are not going to get dramatic increases in performance simply from switching to a higher octane fuel.
If you feel anything at all, you may notice it feel "happier" going up hills.

I also know GM's strategy of blending between two "High" and "Low" octane spark advance tables based on knock feedback, instead of switching between completely different tables like Ford or Honda can set you up for some odd drivability problems (things like "dead spots" in the rev range: car goes, but then hesitates at 2k or something, then starts moving at 3k).

Even so, you car should not act like a "lumpy, inconsistent jittery mess" on 87 octane. Something else is wrong if that is the case.


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## JLL (Sep 12, 2017)

@Morsel , @jblackburn knows that. Most of us on this forum know that. If we would have wanted (or could have afforded) a Type R, or a WRX, we would have bought one.

But, for whatever the reason we bought Cruze's. And for most of us, we enjoyed trying to make our cars better, even if it's not the most economical or reasonable thing to do.

I just wanted to comment because it kinda sounds like you beating a dead horse. 

BTW, please make an introduction thread in the new member introduction section so we can get to know you better.


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## Morsel (May 11, 2021)

JLL said:


> @Morsel , @jblackburn knows that. Most of us on this forum know that. If we would have wanted (or could have afforded) a Type R, or a WRX, we would have bought one.
> 
> But, for whatever the reason we bought Cruze's. And for most of us, we enjoyed trying to make our cars better, even if it's not the most economical or reasonable thing to do.
> 
> ...


I don't want OP thinking he needs to put $50 oil and expensive gas into his commuter car just to make it drive properly.
Hes clearly not happy with how is car is performing. Moderators telling him to pay more for gas and oil isn't going to make him happier.


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## JLL (Sep 12, 2017)

Morsel said:


> I don't want OP thinking he needs to put $50 oil and expensive gas into his commuter car just to make it drive properly.
> Hes clearly not happy with how is car is performing. Moderators telling him to pay more for gas and oil isn't going to make him happier.


I'm going to take off my moderator hat for a second because I don't want people to think I'm smarter than them just because I'm a moderator. I love my Cruze and I love this forum.

I've worked in the automotive service industry for 10 years. I've owned 3 turbocharged vehicles. I can vouch that a turbocharged engine runs better in the long run using premium fuel and oil vs. Low quality fuel and oil.

But, I agree there could be an underlying issue with the OP's car.


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## Cobawlt2010 (May 13, 2021)

Morsel said:


> Look, these cars are slow. That's just the way they are. There is nothing wrong with that, but if you're expecting Type R or WRX performance out of this thing, you're gonna be disappointed. Tuning can address quite a bit of the drivability complaints (especially with the older cruzes), but you're not gonna catch up with other sportier cars.
> 
> Not trying to talk trash, but its important that we're all on the same page in terms of what is realistically achievable out of this car.
> 
> ...


Dang, If you consider the second gen "slow"... then you never drove a 1.8l first gen cruze. I owned one for awhile... that thing was sloowwww... The 8 seconds to 60 of the LE2 compared to 11 of the 1.8l is a big difference... Honestly, I see even quite a large difference between the LUV and LE2. I love this car. If the drivability issues were picked up by the computer it would make my life easier. I put on tons of miles. So going back to the shop that done the trans service might laugh at me now. Since that service I have put on 18k on it... and that was just through winter... I might as well have another service done at this point. I doubt they'd want to help me there without any diag fee. And tbh a trans service is almost the same price as the diag fee anymore. I don't like that the shops around here (yes I know I am saying shops but I really mean dealerships) are all using BG products... I don't like the ****... put in what GM recommends... no cleaning crap... just the fluid... I would only want BG garbage in my car if the manufacturer said to put it in there... I honestly called 3 dealerships to get prices... all three were BG additives... asked about no BG additive and they said since it's BG equipment they wouldn't do that. Hogwash... Might as well take it to a real trans shop to have the work done IMO... Especially considering it didn't do this before the fluid exchange.

I know I said Lucas oil but I also meant AMS oil... I thought it wasn't dexos 2 certified? Am I correct at stating that... I'm not sure why I confused the two...


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## Thebigzeus (Dec 2, 2018)

Amsoil meets the requirements for it, but doesn't pay for the certification to Dexos. Its great oil.


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## Barry Allen (Apr 18, 2018)

Morsel said:


> Meanwhile Dodge, for example, makes absolutely no changes to spark unless IATs are very high.


Hah, the one experience I have with this is helping a guy build a custom cold-air intake for his Ram 2500 with the V-10 engine. 

For the third-generation pickups, the V-10 was only offered in the 2002-2003 models. Dodge redesigned to where the air filter was on the passenger side of the front but the throttle body was on the driver side of the aluminium intake manifold. You couldn't swap the manifold to reverse it because that interfered with the brake booster, and apparently Dodge was unwilling to do anything to redesign that part. The result was the air came through the filter and then ran inside a plastic tube across the front of the engine to make a 180 degree turn and feed into the throttle body. The result when doing heavy towing was a huge amount of heat soak because hot air flowing through the radiator would cause intake air temperatures to soar. Fuel economy when towing was HORRIBLE. Down in single digits because the ECU was running the mixture rich to avoid detonation. That V-10 engine called for 89 octane (most people don't know that) but even 91-93 octane didn't help. The catalytic converters would glow cherry red from all that excess fuel going into the cylinders!

We purchased a spare hood and did some cutting and welding to mount a NACA duct that fed into a custom baffled air box. It wasn't sealed tight, but it did corral enough air to feed a shorty K&N filter that we mounted on the throttle body. The end result was putting performance and fuel economy back where it should have been.


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## Barry Allen (Apr 18, 2018)

Cobawlt2010 said:


> I was told by the dealership there's little point putting premium in it.


They are ignorant on the issue. One of the RPO codes for turbocharged Cruze vehicles is "91 OCTANE RECOMMENDED."


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## Barry Allen (Apr 18, 2018)

Cobawlt2010 said:


> he was with the dealership for over 30 years


Ah, I think I see the problem.

I genuinely mean no offense to older people here, but I'm going to state this as carefully as I can.

He has limited or no experience with modern turbocharged vehicles and his knowledge is out-of-date. He doesn't know what he is talking about.


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## Morsel (May 11, 2021)

Cobawlt2010 said:


> Dang, If you consider the second gen "slow"... then you never drove a 1.8l first gen cruze. I owned one for awhile... that thing was sloowwww... The 8 seconds to 60 of the LE2 compared to 11 of the 1.8l is a big difference... Honestly, I see even quite a large difference between the LUV and LE2. I love this car. If the drivability issues were picked up by the computer it would make my life easier. I put on tons of miles. So going back to the shop that done the trans service might laugh at me now. Since that service I have put on 18k on it... and that was just through winter... I might as well have another service done at this point. I doubt they'd want to help me there without any diag fee. And tbh a trans service is almost the same price as the diag fee anymore. I don't like that the shops around here (yes I know I am saying shops but I really mean dealerships) are all using BG products... I don't like the ****... put in what GM recommends... no cleaning crap... just the fluid... I would only want BG garbage in my car if the manufacturer said to put it in there... I honestly called 3 dealerships to get prices... all three were BG additives... asked about no BG additive and they said since it's BG equipment they wouldn't do that. Hogwash... Might as well take it to a real trans shop to have the work done IMO... Especially considering it didn't do this before the fluid exchange.
> 
> I know I said Lucas oil but I also meant AMS oil... I thought it wasn't dexos 2 certified? Am I correct at stating that... I'm not sure why I confused the two...


Oh I own a 2014 cruze LS 1.8 too - slow, but never had a single problem with it. Easiest car I've ever had to deal with.
Between family and friends I've dealt with 4 of these things. They're very strong underrated little guys
(just not fast, but who cares)

I brought up the "not fast" part because it was in response to that mod's crazy performance issue on regular gas.
The first gen cruzes are easily one of the slowest cars you'd ever drive. If you go from owning anything else to this, expecting it to be more or less the same, you'd think somethings wrong with the car. Their performance concern would simply being the car not meeting their expectations rather than something actually being wrong with the car.

But I'm not saying that to you at all - you have a real issue. I've experienced your exact transmission issue twice. First was a slight overfill when I installed my second trans cooler (yes I have two external coolers :3). Second was when I butchered a trans fast learn, which required the tcm to relearn all the shifts through driving. Boy was that a fun 100 miles 

Second gens are definitely zippier - I haven't owned or worked on one, but I've driven a 2017 hatchback 6 speed. Hell of alot better than the 2012 eco 6 speed my family had.

But back on topic,
Honestly if you mention that you've brought it in with this issue before and tell them how frustrated you are about it, how its making you want to sell it, etc, I'm sure a manager will step it and make it right.

If they still wanna play you, trying to sell you the BG crap or whatever, go ahead and give that trans place a try.

I just dont want them to try and sell you a new transmission - unless they find metal in the fluid I'm almost positive you're not at that point yet.


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## Morsel (May 11, 2021)

Barry Allen said:


> Hah, the one experience I have with this is helping a guy build a custom cold-air intake for his Ram 2500 with the V-10 engine.
> 
> For the third-generation pickups, the V-10 was only offered in the 2002-2003 models. Dodge redesigned to where the air filter was on the passenger side of the front but the throttle body was on the driver side of the aluminium intake manifold. You couldn't swap the manifold to reverse it because that interfered with the brake booster, and apparently Dodge was unwilling to do anything to redesign that part. The result was the air came through the filter and then ran inside a plastic tube across the front of the engine to make a 180 degree turn and feed into the throttle body. The result when doing heavy towing was a huge amount of heat soak because hot air flowing through the radiator would cause intake air temperatures to soar. Fuel economy when towing was HORRIBLE. Down in single digits because the ECU was running the mixture rich to avoid detonation. That V-10 engine called for 89 octane (most people don't know that) but even 91-93 octane didn't help. The catalytic converters would glow cherry red from all that excess fuel going into the cylinders!
> 
> We purchased a spare hood and did some cutting and welding to mount a NACA duct that fed into a custom baffled air box. It wasn't sealed tight, but it did corral enough air to feed a shorty K&N filter that we mounted on the throttle body. The end result was putting performance and fuel economy back where it should have been.


Dude you should of made him a snorkel!

















Man I'd love to have an 8.0 Ram. Those LAs are so fun to work on.


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## jblackburn (Apr 14, 2012)

Morsel said:


> Oh I own a 2014 cruze LS 1.8 too - slow, but never had a single problem with it. Easiest car I've ever had to deal with.
> Between family and friends I've dealt with 4 of these things. They're very strong underrated little guys
> (just not fast, but who cares)
> 
> ...


If you don’t own a Gen 2 or a 1.4T, why are you commenting that they don’t deliver low end power better on premium? They absolutely do. 

I never expected my (stock) Cruze to perform like a GTI or WRX. I just want it to not be a dog around town, and BOTH of my 1.4Ts - one a manual Gen 1, the other an automatic Gen 2 - reacted like that on low octane fuel. It’s seat of the pants noticeable to where even my wife put midgrade in it and said “something felt wrong after I took off from the gas station”.


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## Morsel (May 11, 2021)

jblackburn said:


> If you don’t own a Gen 2 or a 1.4T, why are you commenting that they don’t deliver low end power better on premium? They absolutely do.
> 
> I never expected my (stock) Cruze to perform like a GTI or WRX. I just want it to not be a dog around town, and BOTH of my 1.4Ts - one a manual Gen 1, the other an automatic Gen 2 - reacted like that on low octane fuel. It’s seat of the pants noticeable to where even my wife put midgrade in it and said “something felt wrong after I took off from the gas station”.


First of all, what are you talking about.
I just explained in this post how drivability problems could be setup due to the way GM optimizes spark advance.








2017 Heat soak hesitation / WOT miss shift


So I own a 2017 second gen Chevy Cruze LT. This car has 78k on the odometer and I have been having issues with it for about twenty thousand miles so far. My first issue started around 55k which was a hesitation when hot outside and the car had been heat soaked running on the highway for a...




www.cruzetalk.com













Also, I have the tune right in front of me.








High octane table:








Low octane table:









This is the knock airmass table - the amount of air allowed to enter the cylinder when knock is present.
Basically, this tells you how much boost to pull at a given rpm when the ECM is trying to suppress knock.

For example 0.84g of airmass is what the ECM tries to target when no knock is present.
So take a look at that row in the spark advance table to get an idea of what timing will be set to at full power.









Let me explain in better detail how GM handles spark:
Lets say we are at 2400 rpm commanding 0.60 airmass.
Look at (2400,0.6) on both tables.
High Octane is -2 degrees.
Low Octane is -14.5 degrees.
With no learning values, we target the middle of these two, which would be -8.25.
If no knock is present, we gradually start moving towards the value in the high octane table.
If knock is present, we suppress the event, and gradually start moving towards the value in the low octane table.

So the final spark advance table is generated through knock feedback.
You can probably see how issues can develop - mainly in the transition periods.
If you drive on high octane gas of time in the high octane side, and then either get a bad batch or switch to low octane, there may be quite a bit of knock initially.

Going back to the knock airmass table, if the car pulls 7 degrees of timing in response to knock, its gonna dramatically limit boost. In extreme cases you will feel this as a hesitation.

But once the ECM figures out what blend of the two tables will mostly result in little to no knock, performance becomes a little more consistent.

So now lets say you've been driving close to the low octane table for a while, and then put premium in the thing.
Well now its just not going to knock with that low of spark advance, so its always going to give you full power when you ask for it.
Its going to just keep raising spark towards the values in the high octane table until finally knock starts to occur, and then normalizes from there.

tl;dr You WILL notice performance changes on the higher octane, but they will NOT be considerable enough to warrant the increase in cost.
(Did I not say that either?)









Could we get back onto OP's topic though?
I find it odd that I have to ask a moderator that.


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## Thebigzeus (Dec 2, 2018)

🍿


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## Barry Allen (Apr 18, 2018)

Run a minimum of three tanks of premium fuel and see if the behavior improves. Look for 91-93 octane:






Find 93 Octane Gas: Locate Gasoline Stations Selling Premium


93 Octane Gas Finder. Discover where to find gas stations in your area that have 93 octane gasoline!




find93.com


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## Sourkreme (Feb 4, 2020)

6Speed2016LT said:


> Definitely second the top tier premium gas.......Until I knew better I was running regular 87 Octane gas for the first few years....When I switched to Premium 91+ it was an entirely different car. Especially when hot outside.
> 
> Jason


They told me when I bought mine Do Not used premium gas or ethanol. It would damage the motor. 2017 Cruze LT


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## jblackburn (Apr 14, 2012)

Sourkreme said:


> They told me when I bought mine Do Not used premium gas or ethanol. It would damage the motor. 2017 Cruze LT


Those are both inaccurate statements. The Cruze can run up to E15 no problem (it is in the manual/inside the gas door), and has built-in tables for high octane fuel. MOST fuel in the US is E10.


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## Cobawlt2010 (May 13, 2021)

Can overfilling the transmission with fluid cause damage to the transmission? This is what occurred. How responsible is the dealer for overfilling the transmission for damages? It's not like the darn thing has a dipstick.


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## jblackburn (Apr 14, 2012)

Cobawlt2010 said:


> Can overfilling the transmission with fluid cause damage to the transmission? This is what occurred. How responsible is the dealer for overfilling the transmission for damages? It's not like the darn thing has a dipstick.


Yes. It can cause the fluid to overheat/burn. If you have a record that someone did the service that overfilled the trans and caused it to overheat/fail, they are the ones that caused that failure. Whether or not they see it that way without legal representation may be a different battle altogether.


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## JJOcean (Oct 24, 2021)

I had my doubts after reading this thread but Premium sure does seem to make a difference. My 2018 runs much smoother and with zero hesitation now. Hard to believe that something so simple as a fuel upgrade can make such a difference. I hate paying extra for Premium with fuel costs so high but no way I am living with 87 Octane and the problems it causes.


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## JLL (Sep 12, 2017)

JJOcean said:


> I had my doubts after reading this thread but Premium sure does seem to make a difference. My 2018 runs much smoother and with zero hesitation now. Hard to believe that something so simple as a fuel upgrade can make such a difference. I hate paying extra for Premium with fuel costs so high but no way I am living with 87 Octane and the problems it causes.


More fuel stability make a huge difference.


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## Barry Allen (Apr 18, 2018)

Cobawlt2010 said:


> This was brought up to a technician, not to sales staff. He said 87 is fine. He seemed knowledgeable and he said he was with the dealership for over 30 years.


He sounds old and stuck in his ways.


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