# MAP sensor plugged solid- cleaned and reinstalled



## Carminooch (Mar 23, 2018)

2018 Cruze diesel, RS hatchback. 6spd manual.


As the title states, my MAP sensor was plugged solid. For a while I’ve been experiencing

1.) Deteriorating fuel economy (nothing drastic but enough to notice).

2.) Feels sluggish. Doesn’t have that pep that it had when new.

3.) Upon cold start the car hiccups VERY badly for 2 mins before clearing up. The “hiccup” never, ever, occurs with the RPM’s above exactly 2000 rpm


I took the engine cover off and this helped make room to reveal the MAP sensor. I forget the size of the screw in there but it was a torx.

I removed the sensor and sprayed it down with WD40 and picked out the tar and carbon, which was much harder in texture than I imagined. I don’t have a photo of the “after”.


I reinstalled the sensor, started the car, and the car ran terribly for 30 seconds. It cleared right up after that. I took the car out for a long drive and I can say with absolute certainty that this made a noticeable difference in acceleration and pedal response. Big difference. We’ll see how MPG plays out. I’ve got 50,000 miles.


I can’t comment on the cold start hiccup just yet because I need to let the car sit overnight but I figured I would pass this info along and urge others to carefully inspect their MAP sensor. It’s easy to get to and cleaning it was not difficult.


----------



## Detrious (Jul 5, 2017)

Oh yes, that will be a big help with mileage for sure, now the ecm can accurately see the charge air pressure and temp and adjust fuel accordingly. One thing, last time I cleaned mine at around 100k the o-ring got carbon packed around it and stuck in the bore and it broke off the plastic cage around the temp sensor. I was about to get it out with a right angle pick and replace the sensor but when I went back in with it I lubed the o-ring with a bit of antisieze. I'm getting close to needing to clean it again and I'm hoping it comes right out.


----------



## MRO1791 (Sep 2, 2016)

A known common issue and fix also for the Gen 1 diesel engine. Not surprising to see it is common in both engines. Thanks for posting.


----------



## Carminooch (Mar 23, 2018)

Detrious said:


> Oh yes, that will be a big help with mileage for sure, now the ecm can accurately see the charge air pressure and temp and adjust fuel accordingly. One thing, last time I cleaned mine at around 100k the o-ring got carbon packed around it and stuck in the bore and it broke off the plastic cage around the temp sensor. I was about to get it out with a right angle pick and replace the sensor but when I went back in with it I lubed the o-ring with a bit of antisieze. I'm getting close to needing to clean it again and I'm hoping it comes right out.


Good point, my o-ring was still pliable and wasn’t hard or packed with carbon but this is something I’ll keep an eye on when I go to take a look at this again (inevitably) in the future. Seems this is something I’ll have to routinely do, since the EGR is spewing this crap into the intake. 

20k miles ago I made the dealership address a plugged EGR system. They refused to look at or touch my EGR cooler but as a compromise they replaced the EGR valve in my intake. Flash forward to now, 20k miles later, it’s **** near close to being plugged up again. I learned my lesson and do very little idling if I can avoid it.

Most of my driving is highway driving and I’m pretty spirited when I drive. I really really hate to see what the inside of my intake manifold looks like and I don’t even know where to begin in terms of figuring out how to do it myself as a DIY (no idea where I’d find detailed instructions to remove and reinstall). I doubt I would have even the faintest shred of luck asking the dealership to address the carbon buildup inside there


----------



## Carminooch (Mar 23, 2018)

MRO1791 said:


> A known common issue and fix also for the Gen 1 diesel engine. Not surprising to see it is common in both engines. Thanks for posting.


You’re welcome! It was very easy to get to and wd40 really helped. This is something I’ll be looking at yearly. I don’t mind having a DPF and I can deal with an SCR and adding the exhaust fluid, but the EGR clogging up my intake and stuff is absolutely maddening and I wish I could make it stop


----------



## MP81 (Jul 20, 2015)

MRO1791 said:


> A known common issue and fix also for the Gen 1 diesel engine. Not surprising to see it is common in both engines.  Thanks for posting.


Yeah...something I've been meaning to tackle on our '14...done the EGR/Throttle Valve twice, but never the MAP.


----------



## Detrious (Jul 5, 2017)

MP81 said:


> Yeah...something I've been meaning to tackle on our '14...done the EGR/Throttle Valve twice, but never the MAP.


Oh man. So if it won't budge you can try twisting it a bit back and forth like a stubborn bolt, not too much or it will definitely break. If you're lucky once it seems to move free it should come out, in maybe one piece too! Lol honestly maybe just have a sensor on standby because that plastic does not like all that heat over time.


----------



## MP81 (Jul 20, 2015)

Detrious said:


> Oh man. So if it won't budge you can try twisting it a bit back and forth like a stubborn bolt, not too much or it will definitely break. If you're lucky once it seems to move free it should come out, in maybe one piece too! Lol honestly maybe just have a sensor on standby because that plastic does not like all that heat over time.


Oh boy...sounds like it's going to be a blast. I presume it's at least easy to access? I haven't actually looked for where its at in the car. WD40 doesn't seem like the right thing to clean it off, maybe brake clean will be a better option, though I'm always leery when it comes to a sensor.


----------



## oregon_rider (Jul 21, 2017)

MP81 said:


> Oh boy...sounds like it's going to be a blast. I presume it's at least easy to access? I haven't actually looked for where its at in the car. WD40 doesn't seem like the right thing to clean it off, maybe brake clean will be a better option, though I'm always leery when it comes to a sensor.


 A Guide to MAP Sensor Cleaning

Notes using electrical parts cleaner.



https://www.napaonline.com/en/p/CRC091313?cid=social_blog_082017_PartsCleaner



jeff


----------



## Carminooch (Mar 23, 2018)

Any idea how hard it is to remove the intake manifold? It’s a tight fit. Seeing how my EGR got plugged up, my MAP sensor got plugged up, and now my new EGR is looking close to plugged up again after 20k miles, I really hate to see what the intake looks like inside.

Anyone ever take the intake manifold off?


----------



## oregon_rider (Jul 21, 2017)

I have an alldatadiy account and it has instructions for intake manifold replacement. The book time for replacement is 4.8 hours. Just scanning over the instructions - it looks like alot of stuff to get out of the way to get at it...

Jeff


----------



## Barry Allen (Apr 18, 2018)

Think you can soak that sensor in kerosene or diesel to loosen all that crud?


----------



## rauan (Apr 14, 2021)

Does anyone have the instructions on how to do it? I think I could figure it out myself, but it is a lot easier when you follow someone's work on YouTube


----------



## Carminooch (Mar 23, 2018)

rauan said:


> Does anyone have the instructions on how to do it? I think I could figure it out myself, but it is a lot easier when you follow someone's work on YouTube


Your MAP sensor is where the green circle is in this photo (ignore the red, I took this photo off the internet where someone else was point something unrelated out).

Remove the sensor, very carefully clean using WD40 or kerosine or electrical cleaner and a tooth pick, maybe a cotton swab as well. Inspect your O ring on the sensor to ensure it’s not broken or brittle or missing 

Hand tighten back into place.


----------



## kelmil182 (Jun 7, 2021)

I have about 110K KMs on my 2017 and would like to change out my MAP sensor. Can anyone let me know what the part number is?


----------



## oregon_rider (Jul 21, 2017)

2017-2019 GM Intake Air Pressure and Temperature Sensor 55593802 | Trunk Monkey Parts


2017-2019 GM part # 55593802 - Intake Air Pressure and Temperature Sensor




www.trunkmonkeyparts.com





Jeff


----------



## spaycace (Feb 9, 2012)

I looked into this after stumbling on to this thread and found my MAP to be plugged up like the photos as well ... but unfortunately, I didn't notice any change in MPG after cleaning it thoroughly. I think the tires I purchased are the cause of decreased fuel economy, but I won't really know unless I put another set of OE tires back on it, and check my mileage. I got new tires in the winter, so just figured part of it was the winterized fuel. Last summer, I would get up to 65 mpg on the trip home from work every morning ... this summer, my best has been 58 mpg. Back to the MAP though, so I don't hijack this thread ... having seen this on my own sensor, what other components could be seeing the same type of "buildup" that could cause potential issues down the road? I know these cars have ceramic "glow plugs" and wonder if they could be impacted like this ...


----------



## Carminooch (Mar 23, 2018)

spaycace said:


> I looked into this after stumbling on to this thread and found my MAP to be plugged up like the photos as well ... but unfortunately, I didn't notice any change in MPG after cleaning it thoroughly. I think the tires I purchased are the cause of decreased fuel economy, but I won't really know unless I put another set of OE tires back on it, and check my mileage. I got new tires in the winter, so just figured part of it was the winterized fuel. Last summer, I would get up to 65 mpg on the trip home from work every morning ... this summer, my best has been 58 mpg. Back to the MAP though, so I don't hijack this thread ... having seen this on my own sensor, what other components could be seeing the same type of "buildup" that could cause potential issues down the road? I know these cars have ceramic "glow plugs" and wonder if they could be impacted like this ...


If your MAP is plugged like mine was, your EGR, EGR cooler, and intake all probably suffer from the same carbon buildup. Our cars run a really aggressive EGR tuning that forces a lot of dirty exhaust soot air back into our intakes. Unfortunately there doesn’t seem to be much you can do about it

I’d be happy to run a DPF and even the SCR with the exhaust fluid for emissions, but the EGR just screws everything up


----------



## 6speedTi (May 18, 2018)

Just have to wait for a EGR delete on the second gen diesel.


----------



## Barry Allen (Apr 18, 2018)

6speedTi said:


> Just have to wait for a EGR delete on the second gen diesel.


Yeah, we've been waiting. It's probably never coming. They didn't make many of these vehicles (Cruze, Terrain, Equinox) and they aren't making any more, so the market for any possible tuning or emissions delete is small and shrinking as cars fall out of the fleet (accidents, broken engines not worth repairing, etc.)


----------



## MP81 (Jul 20, 2015)

Barry Allen said:


> Yeah, we've been waiting. It's probably never coming. They didn't make many of these vehicles (Cruze, Terrain, Equinox) and they aren't making any more, so the market for any possible tuning or emissions delete is small and shrinking as cars fall out of the fleet (accidents, broken engines not worth repairing, etc.)


I am a little surprised that at least Trifecta didn't develop a non-delete tune for the 1.6TD vehicles. The 1st gens weren't produced in very high numbers either, though I expect the 2nd gen was even less than that.


----------



## Barry Allen (Apr 18, 2018)

MP81 said:


> I am a little surprised that at least Trifecta didn't develop a non-delete tune for the 1.6TD vehicles. The 1st gens weren't produced in very high numbers either, though I expect the 2nd gen was even less than that.


I think the 1st gen was really easy to tune. My understanding (and I could be very wrong) is that the ECU on the second gen cars is hard to unlock, hard to tune, etc.

I want a car that I can leave the DPF on it. I believe they capture soot well and do good things for the environment by getting rid of the belching clouds of smoke that used to come out the exhaust of diesel vehicles.

However, I do want the ability to turn off EGR. That's the big problem that clogs up and destroys diesel engines.


----------



## MP81 (Jul 20, 2015)

Barry Allen said:


> I think the 1st gen was really easy to tune. My understanding (and I could be very wrong) is that the ECU on the second gen cars is hard to unlock, hard to tune, etc.
> 
> I want a car that I can leave the DPF on it. I believe they capture soot well and do good things for the environment by getting rid of the belching clouds of smoke that used to come out the exhaust of diesel vehicles.
> 
> However, I do want the ability to turn off EGR. That's the big problem that clogs up and destroys diesel engines.


I think you are correct when it comes to their difficulty to unlock.

And again, agreed - I'd love to just delete EGR - and only EGR - and leave everything else intact.


----------



## Blkmagicturbo (Nov 25, 2021)

I found my intake completely gummed up. I had a small leak in my egr cooler that mixed with the soot and tarred. Up my intake as well as the cylinder head intake and valves. I replaced the egr cooler, the gaskets and also pulled the intake to clean it. Here are the pics of the clogged up


----------



## Blkmagicturbo (Nov 25, 2021)

To take the intake off it wasn't as bad as I thought it would be. I removed the engine cover, throttle body, the egr metal pipe from egr cooler to intake, disconnect the sensor harness for egr temp, the map sensor disconnect, disconnect the glow plugs, the fuel lines (I disconnected the fuel rail lines and the one coming off the pump) , a couple brackets, then the bolts for the intake 5 on bottom and 4 on the top. Once the I take was loose I pulled it out the top pass side while rotating it(it just fits see photo below) . I cleaned out the intake with purple power as what was recommended by the Ford diesel guys). It was an absolutely filthy mess, I got soot tar all over, the flapper valves on intake were super caked up as well as the intake. I used info I found on the direct injection gasoline BMW crowd to use berryman's b12 injector cleaner for the cylinder head intake and valves. Make sure you rotate the engine so the valves are closed (otherwise you'll fill up the cylinder with non diesel compatible cleaner). With the valves closed I filled up the runner with berryman's cleaner and use wire brush from harbor freight. Then soak up the dirty solvent with paper towels and repeat.... Several times until the runner looked clean. I used my cell phone camera to take pictures down the runners to see my progress. See the cleaned up photos vs the clogged up ones


----------



## Barry Allen (Apr 18, 2018)

With that much time and effort invested you might as well have done an EGR delete with tuning.


----------



## Barry Allen (Apr 18, 2018)

Plastic manifold, so no change to clean it with a blowtorch:


----------

