# New Member - First Post & Cruze Diagnosis Mystery



## Gr3mlin (Jul 6, 2021)

Hi all, been lurking and soaking up info in the background here intermittently for ~2yrs. Thanks for all the help already. I'm working on a 2012 LT, automatic 1.4L. Location; NC, US. 
Not current on the mileage, but I'd guess ~160k. 

I do have a repair project I'm working on and would appreciate the experience / advice of the community, even if that's just linking established threads I'm having trouble trying to find. 

Here's my short-version rundown of symptoms / situation: 
Waiting on a Valve Cover, a cheap corrugated PCV hose, an Intake Manifold, Ignition Coil, and going to pick up some copper spark plugs. I know the fuel side of the combustion equation could very-well still be a factor, as well as the Ignition Coil electrical connector, the Surge or Purge Valve - whatever it's called, etc.. But I've got to keep the dang thing semi-drivable before I want to risk pulling off that corrugated hose or anything else I'm terrified might crumble at the slightest tug before actually getting to see which Check Valves are toast and if the electrical side of things goes into corroded connectors. After that? We'll see 



And Here's More Depth in Case I Missed a Clue Somewhere (Questions for Help Updated @ End):
Owned ~2years, starting at ~130k miles with basically zero knowledge of previous ownership. 

Problems started with the infamous Stabilitrak / Traction Control / Infotainment shutoff shenanigans. I replaced the Negative Battery Cable and the Infotainment shutoff has not reoccurred. Stabilitrak / Traction Control messages have persisted though.

During that next phase of figuring out what problem remained, I was distracted by coolant system issues (replacing the spontaneously shattering plastic water outlet housing where the radiator hose connects).

At some point, while I was trying to gauge over time whether there were still overall cooling issues, the Stabilitrak / Traction Control notifications became constants at startup and rough idles became normal, worsening into registerable misfires. It was around that time that I became aware of and checked the vent-port of the PCV vacuum regulator, but did not witness the tell-tale hissing/suction of the ruptured diaphragm. So, my hypothesis centered around: an oil leak existing somewhere else, which was causing vacuum failure, which was making the Crankcase run inefficient and hot, which was adding more heat to the coolant system than it was designed for, which was why once/month I'd have to top-off the coolant reservoir.

Some time later, the rough idle and misfires were becoming evident at acceleration (or lack thereof). I kept observing, still not finding any leaks or seeing any serious drop in either the oil or coolant levels. At some point, I checked the Valve Cover diaphragm again and realized that it had failed. We minimized overall driving, but some family/financial emergencies made it so I couldn't do much else other than watch and observe while we continued to use the vehicle.

Fast forward a month, and the only change was that the idling roughness became marginally worse and persistent at every idle - the same with every acceleration.

Then we had to make a late-notice 2 hour trip for a doctor's visit. We left an hour early, and it was going to be interstate @ 65mph the whole way once we got up to speed. (That was the idea, anyway). But one over-rev up to 3k rpm going up a 30degree hill, just to barely keep 50mph, and we were overheated. At first, I thought the worst, thinking we'd blown a seal and I'd just painted the interstate with oil. "It's seized. Everything's fusing together in there right now. Any piston/cylinder in there that's not already conjoined probably looks ready to cosplay as hellraiser with the amount of metal fragments splintered and shredded throughout the place."

But there was oil. And after only about 5 minutes of letting the engine bay breeze off... there was still an almost full reservoir of coolant.

Started the car again. Normal temp. So... we kept driving. Overheated again and stopped. Another relatively quick cooldown without any significant loss evident in either fluid. (Tried again 1-3 more times maybe; same result).

Eventually, our extra hour of leeway for drive-time was gone though. We got them to postpone the appt for two hours, so I decided to let the car cool as much as possible. One good cooldown, then check absolutely everything. In the shade, over an hour. Checked fluids. Still full. So, starting with an engine essentially cooled to the touch, we got back on the road and... yep. Overheat. Pulled off the Ignition Coil at the next stop before, hypothesizing, at my whit's end, that the plugs were just fouled - causing the misfires - and that the excess work and inefficient combustion in the other cylinders was the source of the excess heat.

And somewhere during that drive home, after having to cancel the appointment, where we took back roads and kept the rpms below 2k, pausing at high temp for 2-3 min until normal temp resumed... then realizing that, sitting at idle, I could run the A/C full blast without the digital engine temp gauge showing any increase whatsoever above normal...
It hit me. 

Stabilitrak. Traction Control. 
IGNITION COIL. SPARK PLUGS. 
The cooling system was proving itself to be totally fine. The oil was definitely worn out, but the system itself was closed. But, ignoring the original coolant issues, the Stabilitrak/Traction Control were the beginning. Whether or not those misfires had caused the vacuum failure or not didn't really matter. All the components in those two categories were enough to make the 4-cyl act like we'd swapped it for a lawnmower. And they were all components I'd been hearing were infamous design failures over and over again. 

Anyway... that's what I'm operating under. Waiting on a Valve Cover, a cheap corrugated PCV hose, an Intake Manifold, Ignition Coil, and going to pick up some copper spark plugs. I know the fuel side of the combustion equation could very-well still be a factor, as well as the Ignition Coil electrical connector, the Surge or Purge Valve - whatever it's called, etc.. But I've got to keep the dang thing semi-drivable before I want to risk pulling off that corrugated hose or anything else I'm terrified might crumble at the slightest tug before actually getting to see which Check Valves are toast and if the electrical side of things goes into corroded connectors. After that? We'll see 



*So... Questions:*

I'm having trouble finding a thread specific to the electrical side: 
Namely, is there a way I can test the Ignition Coil now, before I order? Should I replace it anyway? (b/c it seems apparent here that it's prone to failure).
Is there any other component in that line from power source to Ignition Coil to new spark plugs where I should be considering any other suspect(s) in addition? (I am not intuitive when it comes to electrical, so if there are fuses, relays, harnesses, wiring connectors, etc. that I should check with a voltmeter... Let's just say, plz remind me which dial to set the voltmeter to ).
Answered! Thanks @Blasirl 

As far as the compression/vacuum side of things: 
I'm about to start watching specific videos for replacing the Intake, etc. to make sure there isn't anything else connecting to that system which - like the corrugated hose - I should be planning on needing to replace (I saw mention of Brake Booster, Surge Valve, etc.). I'm going to do my best to keep reading here and clipping through youtube videos, but would very much appreciate any guidance or known threads related.
Is it stupid to replace the parts I've listed without doing the turbo oil cooler gaskets as well? (etc.). I understand how replacing the Valve Cover without knowing if the actual PCV Check-Valves in the Intake/hose are functioning is just asking for the new diaphragm to rupture.. I just don't know if any other oil lines, sensor connections, or whatever are pertinent the same way. Answered! Thanks @Blasirl 

Less concerning questions which I could probably keep digging for or just wing an answer to, but still welcome input:
1) Deciphering a decade of posts in multiple threads is a grind. Has the whole .028 vs. .035 gap debate been decided at this point? 18 ft-lbs, yes on anti-sieze, yes on dialectic? Check the springs inside the boot, I saw. I've got a spark plug socket. Copper is shorter overall life but better with heat? Iridium lasts a bit longer, but check the gap at half-life?
Answered! Thanks @Blasirl and @jblackburn 

2) I've seen Andre's kits and will absolutely be looking into doing one of those as soon as life gets back to semi-normal, but would prefer to just buy a $30 corrugated hose POS off amazon and know it could be crumbling like Thanos snapped his fingers 3 months from now, than take a drill anywhere near that engine bay right now. Besides, I'll have an extra Intake to do the mod bench-side after. But can someone clarify for me if his kits eliminate BOTH check-valves? or just the Intake one? I'll just finish watching his install of V3 if no answer, but right now I gotta look elsewhere so I can put these other part orders in asap.
Answered! Thanks @Blasirl 

3) Any recommendations on a good torque wrench for these finer applications? I have it in my notes from these threads that it needs to be inch-pound capable and I've been envying the digital ones for awhile now, but I'll take whatever gets the job done at a decent value. I have snapped some obnoxiously positioned bolts before, so... would prefer to just let the little wrench-robot or analog-click tell me when enough is enough.

4) My experience with RTV / Sealant is... I can't remember if I have any experience with RTV or Engine Sealant. So... I might even have some, but... the last time I went into Autozone and they were out of stock, the guy behind the counter pointed to the Advance across the street and said, "Have you tried Autozone?" So... if there's a temperature specification or if silicone is better or something... I trust you guys more.

5) When I fixed my earlier coolant issue with that water inlet connection point shattering, I wanted to pressurize the coolant system as much as possible before committing to turning the engine on and adding actual heat/pressure to the mix. So I removed the little plastic piece (vent chute?) adjoining at the neck of the coolant reservoir - plugged that (vent chute?) with a rag, and pressurized the system as much as I could with my mouth. (Sexy, I know). It worked, though. But... I dropped that little vent-chute thing down the wheel-well a week later when replacing the stupid plastic housing water inlet POS with another just like it. To be clear, the coolant system holds pressure. I don't see/smell any vapor or hear any whistling or hissing from that plug-in vent hole or whatever. When the car was really overheating that first time though, and coolant was recirculating back into the reservoir and (probably) bubbling with a boil - Little spits of coolant were purging out that little channel where the chute-thingy was supposed to clip in. Anybody know if that piece is in anyway functional beyond an overflow gutter to aim down and away from the battery / electrical boxes?
Answered! Thanks, @Hoon


Last info Quick List in case you have questions regarding other root problems:
No white smoke. No evidence of substantial oil or coolant consumption. No milky oil, as far as I know. No coolant residue evidenced anywhere near spark plugs/cylinders at this point. Um... what else would you guys ask... I'm pretty sure the oil line between the turbo and filter has been replaced at some point. No leaks apparent there. No idea what the state of the turbo oil cooler behind the heat shield is, apart from - like I said - no evidence of any substantial oil loss.


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## Blasirl (Mar 31, 2015)

Gr3mlin said:


> Hi all, been lurking and soaking up info in the background here intermittently for ~2yrs. Thanks for all the help already. I'm working on a 2012 LT, automatic 1.4L. Location; NC, US.
> Not current on the mileage, but I'd guess ~160k.
> 
> 
> ...


Welcome Aboard!

That is an epic post and somewhat difficult to read. If you like to write, at the end or even at the beginning of your posts I would suggest you add a TL;DR (Too Long; Didn't Read) addendum. Be very concise what your issues are and what you need t know. You will get far more answers to your inquiries.

That said, I happened to have a bit of extra time so I tried to decipher what was going on.

*Question 1:*

Coil Pack TSB
coil diagnosis video
 coil pack fix 
coil ground

Tips to ensure no misfires occur:

Remove the coil pack. If the boots are stuck on, use a small screwdriver or pick with some dielectric grease on it to go around the outside of the boot and then possibly the inside of the boot to help aid in removal.

Remember to (p)re-gap your plugs to .028, (0.24 if tuned)

*Set gap with the black portion of this tool.*










To increase the gap size bend the ground strap up to the desired height. DO NOT LET THE GAPPING TOOL TOUCH THE *IRIDIUM* CENTER ELECTRODE OR PORCELAIN.

*Measure the gap with feeler gauges.*










*Throw this away.*












Torque to 18 ft-lbs with no anti-seize on the threads of a stock type plug.

Ensure the boots have no rips/tears or holes in them, lightly coat them with dielectric/silicone grease and make sure the resister springs are clean and not caught up in the boots when you install them.

If the plugs look bad, consider these:

*-BKR8EIX-2668* (iridium plugs), ~$25, expect ~10-15k regaps on these, ~40-50k overall life.
*-BKR7E-4644* (nickel/copper plugs), ~$8, expect 15-25K out of these plugs, with a regap or two required at 5-8k intervals on stock tune.

Read _Hesitation Gone!_ for more info on the plugs.






A good replacement coil is the MSD Blaster OEM Replacement Coilpack 8236


*QUESTION 2:*

If the turbo cooler is not leaking, I would leave it be. Install the fix-kit and the replace the corrugated line. I would get both from Andre myself. This will eliminate many of the issues. This fixes the failing orange nipple in the intake manifold and thie linked kit does not require a drill. The Turbo side PCV usually does not fail.








V3.4+ GM 1.4L Turbo PCV Fix/Upgrade Kit


V3.4+ PCV Fix Kit This fix kit addresses the intake manifold check valve failure on the GM 1.4L Turbo LUV/LUJ and eliminates the need to replace your intake manifold. This kit has been improved and proven since 2019 and uses a number of custom designed fittings, check valves, and hardware. Note...




cruzekits.com






https://cruzekits.com/shop/ols/products/gm-14l-turbo-luvluj-pcv-pipe-replacementupgrade-kit


*2011-2016 Cruze 1.4 PCV Valve Cover/Intake Manifold Issues*

Cooling system

Replace the water outlet, thermostat , coolant tank and coolant tank hose when needed. I buy Duralast and/or Mahle parts with a lifetime warranty as you will probably replace them again later.
Random Links
coolant links
trouble shooting temp sensors
 Water Pump TSB
Burp the tank video
 collateral damage 
Normal Coolant Temp 


Don't forget to introduce yourself and your Cruze here as I moved this to the appropriate sub-forum.


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## Gr3mlin (Jul 6, 2021)

Blasirl said:


> Welcome Aboard!
> 
> That is an epic post and somewhat difficult to read. If you like to write, at the end or even at the beginning of your posts I would suggest you add a TL;DR (Too Long; Didn't Read) addendum. Be very concise what your issues are and what you need t know. You will get far more answers to your inquiries.
> 
> ...


You're a legend. Those coil related links are incredible and I never would have found them otherwise. Same with the Spark Plug thread - I feel like I was searching/scrolling forever but that was nice and concise. All of are great, so thank you for taking the time.

Sorry it was wordy. I know circumstances / conditions when things occur can be important factors - and I was terrified there was some clue in the order things happened that I was missing but someone else might recognize. I'll be more brief in the future for sure. 
Peace!


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