# Sticky  Diesel Emissions Sensor Number and Location



## oilburner (Jun 13, 2013)

Rev ...... just one o2 sensor an its pre DPF an it has 3 exhaust temp sensors, top an bottom of dpf an pre def injector in exhaust pipe.


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## diesel (Jun 8, 2013)

Great idea for a post!


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## revjpeterson (Oct 2, 2013)

oilburner said:


> Rev ...... just one o2 sensor an its pre DPF an it has 3 exhaust temp sensors, top an bottom of dpf an pre def injector in exhaust pipe.


updated original post to reflect this


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## diesel (Jun 8, 2013)

I'm guessing you've seen this? It's not exactly straightforward:

EGR SYSTEM for 2014 Chevrolet Cruze (Diesel)


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## revjpeterson (Oct 2, 2013)

diesel said:


> I'm guessing you've seen this? It's not exactly straightforward:
> 
> EGR SYSTEM for 2014 Chevrolet Cruze (Diesel)


Yeah. That's one of the three diagrams across which the emissions components are spread. That particular diagram drove me crazy when I was doing my Particulate Matter Sensor search, because that sensor, and a few others do not show up on any parts diagram at all. Kind of infuriating when trying to work on the vehicles. Hopefully the service/repair manual has better diagrams, but by the time I get my hands on one at a price I can afford, we may have already put all the pieces together ourselves, making it unnecessary. 

You'd think they would just create a diagram of the exhaust stream from the manifold through the turn-down and diagram all of the sensors in the locations they're installed. Instead, they have them floating out in thin air with no indication where the sensor you're seeing inserts or where the sensor you know the location of on your car is in the diagram.


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## diesel (Jun 8, 2013)

I seem to remember somebody posting a diagram on here that listed all the sensors, but I can't find it.


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## Scott M. (Apr 23, 2013)

This is a great picture


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## revjpeterson (Oct 2, 2013)

Scott M. said:


> This is a great picture


That's a good diagram. Even though it doesn't have the various twists and turns of the pipe, and some of the locations are slightly off (NOX2, for example, should be on the other side of the pipe), it at least provides the order they come in the stream. I see a few naming differences and location details that vary from what I have compiled above, so when I get a chance, I'll have to edit the original post to reflect those corrections. Thanks for posting the diagram!


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## diesel (Jun 8, 2013)

Scott M. said:


> This is a great picture


That's the one I was talking about


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## revjpeterson (Oct 2, 2013)

I got the picture of sensors in the front of the engine bay today. (Hopefully I can get the remaining under-car sensors next time I have it lifted up.) 

Here's my first shot at labeling this photo. It's difficult to translate from the diagram above to the real-life photo, so look it over and see if you agree with my labeling or if I need to make some revisions.


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## revjpeterson (Oct 2, 2013)

OP updated with 2 photos and revised descriptions


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## diesel (Jun 8, 2013)

I love this thread, a great resource!


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## revjpeterson (Oct 2, 2013)

Found out while looking under the hood today and looking up part numbers on some of the sensor modules that I have the labels NOX1 and O2 reversed in my under-hood photo. When I have a chance, I will re-label the photo to correct the mistake. I also discovered the location of the DPF Pressure Sensor and lines (hidden in plain sight), so I plan to add a photo and description of its location, along with part numbers for many of these sensors, which I've discovered in my search for a decent price on NOX2 for my Cruze, when I do that as well. 

In addition, I discovered a new sensor while I had the engine cover off. There is a sensor that looks a lot like the EGT sensors which appears to be inserted directly to the exhaust manifold (pre-turbo, near the front-driver's side corner of the engine). I wasn't previously aware that this sensor existed, and it isn't listed in the diagrams that I can recall, so it looks like I'll be trying to research what this sensor is/does.


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## revjpeterson (Oct 2, 2013)

I had time today to swap the location descriptions for O2 and NOX#1. I also added all of the part numbers, including both the original part number (for those of us with early 2014 builds) and the updated part numbers (original to 2015 and later 2014 built vehicles and used as replacement parts for those of us with older builds). 

My preliminary conclusion about the newly-discovered sensor is that it is the EGR Temp Sensor. I have included that definition, but continue to research to confirm this conclusion and would welcome input from others about this sensor and its location/definition. 

I still need to update the labels on the photo of the DPF area (and add photos of EGT#3, EGR Temp, and the Differential Pressure Sensor). Hope to do that on a rainy day when I have time to dig into the photo editing software or once I finish all my fall outdoor work that is hanging over my head.


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## revjpeterson (Oct 2, 2013)

Completed major update of the OP this afternoon: Additional photos, corrected labels, finished adding part numbers (except for EGT#3), updated some info, and included note that the repair How-to for NOX#2 is identical to the Particulate Matter Sensor, except that you replace the neighboring sensor and trace it to a module on the other side of the fuel filter.


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## BradHerr (Sep 29, 2013)

You may need to re-look at the Differential Pressure Sensor location and hoses. It appears the hose labeled "pre DPF line" actually routes to the turbo variable-vane actuator and the hose labeled "post DPF line" goes to some sort of vacuum reservoir on the front of the engine. 



-Brad


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## DECruzer (Jul 19, 2015)

Thanks for this. Very educational for those still learning. Now I'm wondering what have I got myself into....


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## revjpeterson (Oct 2, 2013)

BradHerr said:


> You may need to re-look at the Differential Pressure Sensor location and hoses. It appears the hose labeled "pre DPF line" actually routes to the turbo variable-vane actuator and the hose labeled "post DPF line" goes to some sort of vacuum reservoir on the front of the engine.
> 
> 
> 
> -Brad


You're right. I based that info on a too-hasty look at the parts and I crossed up the paths of the lines with those of similar neighboring hoses when I was tracing their path. I re-examined yesterday and found out that the part number traces back to the turbo actuator. I'll edit the OP to remove that erroneous info. Looks like it's time for me to start researching that DPS again to figure out where it is.


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## IndyDiesel (May 24, 2015)

I am new to having a diesel. Any idea what the various sensors and DPF cost if out of warranty? What a great thread, great work Rev. Thanks so much:eusa_clap:


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## Tomko (Jun 1, 2013)

Stickied.


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## Snipesy (Dec 7, 2015)

BTW that is not the differential pressure sensor, it is a vacuum for the actuator for the turbo vanes.

The differential pressure sensor pipes loop down and right (looking from front) around the ecm to the back of the engine. Then it should be hovering around the intake manifold on a bracket.

It's dumb.


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## OkieTD (Jun 17, 2014)

This thread makes me happier than it should.


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## diesel (Jun 8, 2013)

Tomko said:


> Stickied.


Did it un-stick?


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## Tomko (Jun 1, 2013)

diesel said:


> Did it un-stick?


I wonder if it was unstuck when the new gen1 format was released. 

Nevertheless, I am sticking it again.


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## revjpeterson (Oct 2, 2013)

Snipesy said:


> BTW that is not the differential pressure sensor, it is a vacuum for the actuator for the turbo vanes.
> 
> The differential pressure sensor pipes loop down and right (looking from front) around the ecm to the back of the engine. Then it should be hovering around the intake manifold on a bracket.
> 
> It's dumb.


You're right. I didn't realize that an old thumbnail from before I updated the post a few months ago was still attached. I got in and deleted that thumbnail today.


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## Cruz15 (Mar 17, 2016)

Do you know where the map sensor is?


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## BradHerr (Sep 29, 2013)

Cruz15 said:


> Do you know where the map sensor is?











It is on the intake manifold. It is hard to get a picture of. Mine was all sooted up at one time. Haven't checked it in a while. It sits just downstream from the EGR hose in the intake. 


Sent from AutoGuide.com Free App


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## BradHerr (Sep 29, 2013)

Sent from AutoGuide.com Free App


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## Cruz15 (Mar 17, 2016)

BradHerr said:


> View attachment 194730
> 
> 
> 
> Sent from AutoGuide.com Free App


That is exactly why I want to clean mine. Thank You. Is it easy to remove?


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## BradHerr (Sep 29, 2013)

Cruz15 said:


> That is exactly why I want to clean mine. Thank You. Is it easy to remove?


Yes, it is just one bolt. I didn't notice a difference after cleaning it, but there is no way it was operating at full capacity. 


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## Cruz15 (Mar 17, 2016)

Figured it out was actually pretty sooty. Thank You.

Edit and update

On my Cruze with this sensor clean it was quite amazing the difference.
Just the sound at idle, it really quieted down and my low rpm torque came back.
Its much easier to accelerate with very little throttle compared to before and after.
Im am going to have to do this probably every 10,000 kms or 6250 miles. Ill see how it goes.
Cheers.


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## diesel (Jun 8, 2013)

Very interesting. I never even looked at mine, but I never noticed any drop in power either.


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## Danny5 (Dec 22, 2011)

revjpeterson said:


> *Exhaust Gas Temperature Sensor #1 *(pre-DPF) - Next to (right of) NOX#1 Sensor, between Turbo and DPF. Original Part#: 55583113, New Part#: 55598259
> 
> *Exhaust Gas Temperature Sensor #2* (mid-DPF) - Inserts onto front of the DPF unit at the border between the Oxidation Catalyst stage and the Particulate Filter stage. Part#: 55581034*
> 
> Exhaust Gas Temperature Sensor #3 *(pre-SCR) - upstream of DEF injector Part#: 55581035


So I think the #2 and the #3 sensor part numbers are wrong (switched). I had gone off this thread:

http://www.cruzetalk.com/forum/201-...5961-part-number-exhaust-temp-sensor-2-a.html

but after replacing sensor #2 with 55581035, I am now getting (a week later) a P20E4 code. So coming back this thread, thinking I might need sensor #3.

Now, if you look up 55581035 on Amazon it shows a curved sensor, like what was in position #2 of your picture. Part 55581034 shows a straight sensor, like in the downstream position 3. I double checked this against GMPartsDirect.

Description of 55581034: CRUZE, CRUZE LIMITED; 2.0L; DOWNSTREAM; EXHAUST TEMP SENSOR; POSITION 3
Description of 55581035: CRUZE, CRUZE LIMITED; 2.0L; DOWNSTREAM; EXHAUST TEMP SENSOR; POSITION 2

Can anyone verify this? I would hate to think I put the wrong sensor in position #2 in my car. However, it was an exact match of what I took out...


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## revjpeterson (Oct 2, 2013)

Danny5 said:


> So I think the #2 and the #3 sensor part numbers are wrong (switched). I had gone off this thread:
> 
> http://www.cruzetalk.com/forum/201-...5961-part-number-exhaust-temp-sensor-2-a.html
> 
> ...


I've been trying to find this answer myself since it was raised in the other thread. The part numbers in my OP here are based on the descriptions given in the RockAuto.com catalog at the time it was written. I know that another user has seen the numbers used as you describe above in a work order written by the dealer who replaced his sensor. As more evidence comes in and the part becomes more readily available, it is looking like I might need to revise the OP to reverse those part numbers. The difficulty with these EGT sensors is that I can't find the part number imprinted anywhere on the part itself, which is the method I used for identifying many of the other sensors, leaving us to rely on secondary evidence to discern the correct part numbers.


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## Snipesy (Dec 7, 2015)

EGT2 is the bent one. I dont know what the part number is. Make sure it didn't fall out on you like it did for me once.


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## Danny5 (Dec 22, 2011)

revjpeterson said:


> I've been trying to find this answer myself since it was raised in the other thread. The part numbers in my OP here are based on the descriptions given in the RockAuto.com catalog at the time it was written. I know that another user has seen the numbers used as you describe above in a work order written by the dealer who replaced his sensor. As more evidence comes in and the part becomes more readily available, it is looking like I might need to revise the OP to reverse those part numbers. The difficulty with these EGT sensors is that I can't find the part number imprinted anywhere on the part itself, which is the method I used for identifying many of the other sensors, leaving us to rely on secondary evidence to discern the correct part numbers.


Well, you're in luck! I still have the sensor I removed from position #2 on my shelf, so I looked on it to find a part number. Lo and behold!!!


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## rvblacksmith (Dec 7, 2016)

I have 2011 diesel cruze and part number for my EGT sensor 2 is 25183657.


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## diesel (Jun 8, 2013)

rvblacksmith said:


> I have 2011 diesel cruze and part number for my EGT sensor 2 is 25183657.


This thread is specifically for the US Cruze. Yours will likely be different.


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## Danny5 (Dec 22, 2011)

*A cautionary tale*

So I've been getting the dreaded EGT codes lately. About 2 months ago, I replaced EGT#2.

However, I was still getting some intermittent codes, and I naturally assumed EGT#3 also had to be replaced. This sensor gave me some troubles, so let's get you some helpful tips.

First, the #3 sensor is only 6" forward of the DEF injector, and on top of the pipe. You can almost see it by looking down the back of the engine bay. The sensor wire is clipped to another wire, and then has it's own clip that fits around a small pipe on the back of the engine. Access from under the car should be done from the Passenger wheel area. I removed the wheel for more clearance for my fat ass. 

Here is the tricky part:








It's clipped in an open connector on the back of the engine towards the top. A little wiggle will pull it out of the clip so you can access the connection better. Pull up on the red lock clip, and separate the connector. Note orientation! There is a mark on the egt plug, so I wanted to make sure the same mark went the same direction when putting it back together.

Now a 17mm will fit on the sensor itself, but when mine broke loose, it was in the direction of the DEF injector, and I broke it. I tried to MacGyver it back together, but the def line is high pressure...

















Breaking the def injector is a $450 repair at your local dealer. 









My suggestion is to save money by buying EGT#3, but also SAVE money by letting the dealer replace it.


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## mkohan (Dec 19, 2015)

Danny5 said:


> So I've been getting the dreaded EGT codes lately. About 2 months ago, I replaced EGT#2.
> 
> However, I was still getting some intermittent codes, and I naturally assumed EGT#3 also had to be replaced. This sensor gave me some troubles, so let's get you some helpful tips.
> 
> ...


OUCH thanks for the heads up


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## diesel (Jun 8, 2013)

Yes, thanks for posting about that. It stinks that it happened, but you might definitely save others trouble!


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## sparkola (Jun 9, 2014)

I changed mine from the top of the engine compartment with a couple of rachet extensions. That way the only thing you might break is the ol knuckles


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## Danny5 (Dec 22, 2011)

sparkola said:


> I changed mine from the top of the engine compartment with a couple of rachet extensions. That way the only thing you might break is the ol knuckles


Interested to hear how you did this. None of my ratchets would fit over a sensor with a 3' wire coming off of it!


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## BradHerr (Sep 29, 2013)

I believe a socket like these with an extension would get around the wire.





















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## Rebooter (Mar 27, 2020)

I just replaced EGT#2 and 3. Hope to keep the P20E4 away now, changed them with 1k miles space.


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## Schutze_hun (Mar 27, 2020)

Hi, guys, maybe some one can help me. I have a 2013 2.0Diesel Cruze. On a highway ca. at 140 km/h had reduced engine power message on screen. The ODB code was P0101->MAF sensor issues. First, I ve tried to clean the sensor, then I have changed it, but the problem is still there, at 140 km/h (90mph/h?) Have u got any idea?


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## Snipesy (Dec 7, 2015)

Schutze_hun said:


> Hi, guys, maybe some one can help me. I have a 2013 2.0Diesel Cruze. On a highway ca. at 140 km/h had reduced engine power message on screen. The ODB code was P0101->MAF sensor issues. First, I ve tried to clean the sensor, then I have changed it, but the problem is still there, at 140 km/h (90mph/h?) Have u got any idea?


Intake tampering, EGR tampering, intake leak, or EGR is clogged.

P0101 does not cause REP so you are probably missing something.


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## revjpeterson (Oct 2, 2013)

Update: The Diesel Particulate Matter Sensor's part number has been superseded again. It is now 12662647


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## Roger Ramjet (Oct 11, 2018)

Great Thread. Belated Thanks!!!


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