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Discussion Starter · #21 · (Edited)
Drove it about 10 miles numbers were insane on NOx 2 like 50% to 200% of #1. And NOx 2 would not go to 0. Pulled into my dad's house and engine light came on. I checked the code and p20ee. Leaving my dad's the numbers were instantly better 10-20%. About perfect if I had to guess. NOx 2 would go to 0 when coasting too. So I drove about 15 miles like that on country roads.

Stopped turned car off and back on. Started driving numbers were crazy again. After about 5 miles fluid quality came back up. Shortly after the light the numbers went perfect again. Within 10 miles the the message went away country roads again.

So... I cycled the engine again. And the numbers are insane again. They remained elevated. I stopped and ate some food in the car. Left it idling while I ate. After this the numbers made no more logical sense. NOx 2 was just off in its own world at this point. This drive was 28 miles. I stopped right in the middle. This was very mixed driving.

The exhaust fluid light didn't come back on after it went off during part 2. Don't know how because the numbers were ridiculous. Engine light still on.

So I'm thinking the def injector is sticking open a little. During highway it can clear out and the numbers normalize. But during mixed driving the fluid is building up in the system.
 

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Discussion Starter · #22 ·
Def injector is ordered. Really not thinking that's it though. Whatever is causing the numbers to go askew is corrected when the engine light illuminates. Within a few miles of the light the numbers go where I think they should be.

I'm just gonna keep driving it as long as I can avoid the death clock. I think some miles on it will help. The battery just sat flat dead for 2 months, then I cranked the dog **** out of it for several days while spraying cans of ether down it's throat. When I finally figured out the problem and started it there was an injector stuck wide open, smoking the garage and my neighbors out. I am a heavy equipment operator and I have never seen more white diesel smoke than this car was producing. Then I drove it with 1.5 qts too much oil and the egr unplugged for 150 miles.

So I'll keep clearing the code and putting miles on her. Probably do a service Regen once a week. But I really think the miles will help clear out all the debris I just put into the exhaust. And that in turn will help me get to the bottom of this.

Until then I'm open to suggestions. The new def injector will be here early next week according to the tracking. The one that's in there now is original I believe
 

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Discussion Starter · #23 ·
Well I got code p0420, p20ee, and fluid quality poor. Cleared codes. Did dpf regen, ran quality test. Drove the car for 10 miles. Then 20, then 20. Then 70. And another 70. Finally lights came back on all 3. P0420 is catalytic converter code. I did find it can be triggered by too much oil. Which mine was 1.5qt over full. So could that have ruined the dpf?
 

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Discussion Starter · #24 ·
Put the new def injector in. Now I have codes. P20ee, p0420, p205b, and b2aaa.

Ran a Def Fluid test but after about 30 minutes gretio froze up and the test stopped. All lights still on.
 

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Discussion Starter · #25 ·
I finally gave up. I bought a flashscan 3 and flashed it with a new tune. This turned out a new clue in my hunt.

The NOx 1 reading on the new tune is around 500-600ppm cruising at 60mph. Previously the NOx1 reading at 60 was around 200ppm. Which would mean my car had to spray about 3x the amount of DEF to achieve the correct NOx reduction. Which connects a lot of dots for me.
Examples: 1. the really long amount of time it took to achieve proper ratios.
2. The bizarre #s I get during city driving which indicated that it was over spraying and soaking the SCR with liquid def.

I've looked for open recalls, but found none. I have had a sneaking suspicion in the back of my mind that the car was never updated with the new parameters for the updated sensor. The sensor is updated I did confirm that, part #. So if the new tune I just put on it updated the parameters then now all the sudden the sensor is reading the correct #s??

Can someone who has a good running car please tell me what your #'s are at full temp 60mph and full temp idle. Thanks
 

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I finally gave up. I bought a flashscan 3 and flashed it with a new tune. This turned out a new clue in my hunt.

The NOx 1 reading on the new tune is around 500-600ppm cruising at 60mph. Previously the NOx1 reading at 60 was around 200ppm. Which would mean my car had to spray about 3x the amount of DEF to achieve the correct NOx reduction. Which connects a lot of dots for me.
Examples: 1. the really long amount of time it took to achieve proper ratios.
2. The bizarre #s I get during city driving which indicated that it was over spraying and soaking the SCR with liquid def.

I've looked for open recalls, but found none. I have had a sneaking suspicion in the back of my mind that the car was never updated with the new parameters for the updated sensor. The sensor is updated I did confirm that, part #. So if the new tune I just put on it updated the parameters then now all the sudden the sensor is reading the correct #s??

Can someone who has a good running car please tell me what your #'s are at full temp 60mph and full temp idle. Thanks
I was always told the specific ppm numbers didnt matter so much. I do not believe the sensors are all that accurate they are more for comparing the NOx drop not necessarily the NOx concentration.

But we want NOx 2 to be about 80% 20% of NOx 1 under normal driving conditions. You may not always get that. Especially if its really cold and the engine is struggling to heat up the cat.
 

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I was always told the specific ppm numbers didnt matter so much. I do not believe the sensors are all that accurate they are more for comparing the NOx drop not necessarily the NOx concentration.

But we want NOx 2 to be about 80% of NOx 1 under normal driving conditions. You may not always get that. Especially if its really cold and the engine is struggling to heat up the cat.
It's really bad when NOx2 is reading 10x higher than NOx1. :LOL:

But that's a different problem.
 

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I finally gave up. I bought a flashscan 3 and flashed it with a new tune. This turned out a new clue in my hunt.

The NOx 1 reading on the new tune is around 500-600ppm cruising at 60mph. Previously the NOx1 reading at 60 was around 200ppm. Which would mean my car had to spray about 3x the amount of DEF to achieve the correct NOx reduction. Which connects a lot of dots for me.
Examples: 1. the really long amount of time it took to achieve proper ratios.
2. The bizarre #s I get during city driving which indicated that it was over spraying and soaking the SCR with liquid def.

I've looked for open recalls, but found none. I have had a sneaking suspicion in the back of my mind that the car was never updated with the new parameters for the updated sensor. The sensor is updated I did confirm that, part #. So if the new tune I just put on it updated the parameters then now all the sudden the sensor is reading the correct #s??

Can someone who has a good running car please tell me what your #'s are at full temp 60mph and full temp idle. Thanks
What is this flashscan 3 you speak of? Also, did you ever resolve the issue? I purchased a 2014 CTD with 180k on the clock. All was good for about a month then SHTF. I keep getting the p2002 code from time to time with the Def Quality warning popping up. When I get the warning I drive in manual mode in 1 gear lower on the interstate. Within 15 miles the warning goes away. After that I force a regen while driving and all warnings and check engine lights stay at bay for about 5 days. When I hit 400 miles after a regen or 10 grams of calculated soot mass, the def quality warning pops up. If i regen before the 400 miles, I wont see a warning.

Components I have replaced.
DEF heater
Def Module (to the right of the pump on the tank)
NOX 1
NOX 2
Def Fluid Injector
Both Gaskets on front and rear of SCR pipe
Glow Plugs
Air Filter
DPF differential pressure sensor
Wastegate Solenoid
Removed and Cleaned EGR Valve

I will also note that every component I changed was genuine. I have also read that this issue was related with a "software anomaly" and have the most current emissions updates in the ECM.
 

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What is this flashscan 3 you speak of? Also, did you ever resolve the issue? I purchased a 2014 CTD with 180k on the clock. All was good for about a month then SHTF. I keep getting the p2002 code from time to time with the Def Quality warning popping up. When I get the warning I drive in manual mode in 1 gear lower on the interstate. Within 15 miles the warning goes away. After that I force a regen while driving and all warnings and check engine lights stay at bay for about 5 days. When I hit 400 miles after a regen or 10 grams of calculated soot mass, the def quality warning pops up. If i regen before the 400 miles, I wont see a warning.

Components I have replaced.
DEF heater
Def Module (to the right of the pump on the tank)
NOX 1
NOX 2
Def Fluid Injector
Both Gaskets on front and rear of SCR pipe
Glow Plugs
Air Filter
DPF differential pressure sensor
Wastegate Solenoid
Removed and Cleaned EGR Valve

I will also note that every component I changed was genuine. I have also read that this issue was related with a "software anomaly" and have the most current emissions updates in the ECM.
First verify that you don't have any other codes set.
If that is the case, then with the engine idling and at operating temperature, verify that there is very light or no black smoke visible at the tailpipe when performing several accelerator pedal sweeps by rapidly depressing the throttle pedal to WOT and back to rest. Let the engine rest about 5 seconds between sweeps.
If you get a lot of black smoke, then your DPF is likely defective.
If you don't get black smoke, then check for leaks in your exhaust system.
If you don't find any leaks or damaged components, then look for restrictions in the air intake, leaks in the intake ducts, a cracked or damaged MAF sensor housing, a faulty MAF sensor (skewed, stuck in range, or slow response), and also make sure the the MAF is clean of debris.
 

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First verify that you don't have any other codes set.
If that is the case, then with the engine idling and at operating temperature, verify that there is very light or no black smoke visible at the tailpipe when performing several accelerator pedal sweeps by rapidly depressing the throttle pedal to WOT and back to rest. Let the engine rest about 5 seconds between sweeps.
If you get a lot of black smoke, then your DPF is likely defective.
If you don't get black smoke, then check for leaks in your exhaust system.
If you don't find any leaks or damaged components, then look for restrictions in the air intake, leaks in the intake ducts, a cracked or damaged MAF sensor housing, a faulty MAF sensor (skewed, stuck in range, or slow response), and also make sure the the MAF is clean of debris.

No smoke at all out of the tailpipe. I was considering using a fogger to find a leak in the exhaust because I cant see or hear any leaks. No other fault codes. The intake manifold was caked up with soot like all of them seem to be and I forgot to mention in the previous post that I did put a new MAP sensor in as well. The person I did buy the car off of had the Intake pipe crack and he neglected it for quite some time. I put a new one of those on as well. MAF was cleaned.
 

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If you have checked all of that stuff and you make sure you don't have any intake or exhaust leaks, then the diagnostic troubleshooting tables would have you replace your DPF. Have you ever got a P24AE code? That would be related to the DPS (Diesel Particulate Sensor) towards the back of the exhaust behind the 3rd NOx sensor. Also...are you sure your MAF is functioning properly?
 

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If you have checked all of that stuff and you make sure you don't have any intake or exhaust leaks, then the diagnostic troubleshooting tables would have you replace your DPF. Have you ever got a P24AE code? That would be related to the DPS (Diesel Particulate Sensor) towards the back of the exhaust behind the 3rd NOx sensor. Also...are you sure your MAF is functioning properly?
I am working with a Snap On Solus Ultra, so I can monitor the MAF. I honestly have no clue what I am looking for, though. I have never experienced a P24AE code. The only leak a fogger indicated for the intake side was the intake pipe, which was replaced.
 

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Discussion Starter · #33 · (Edited)
I am working with a Snap On Solus Ultra, so I can monitor the MAF. I honestly have no clue what I am looking for, though. I have never experienced a P24AE code. The only leak a fogger indicated for the intake side was the intake pipe, which was replaced.
Yes after 15,000 miles I came to find that the scr was clogged and collapsing in on itself. I just found this last week. During the beginning the only symptom, other than a plethora of codes that came up, was low performance. Particularly low boost.At first it was just a little low 220 kpa max). But just before I found it I was struggling to reach 170 kpa. My egt were running around 500c cruising.

The parts I changed were:
Map
Maf
Def injector
Egr
Nox 2
O2
Vacuum pump
Egt sensor 2
Turbo
Intake temp sensor
Accelerator pedal

Probably more. But this is all I can think of right now.

I did also have one more symptom which I didn't know was a symptom until I fixed it. The transmission was rough/ firm shifting both up and down. Now that it's fixed the shifting is actually on the mooshy side.

Pull up your desired boost pressure and also your actual boost pressure. And see if it is making the correct amount of boost. If it's not then you may have a restriction in your exhaust. Such as a plugged dpf or a plugged scr. To check the the scr I took loose the 3 bolts at the bottom of the downpipe to let excess pressure out. Took about 5 minutes and the increase in boost was immediate.

Now that it's fixed my egt are down around 330c
My coolant temp is down 20f
The trans shifts better
About 3 times the amount of torque
And I picked up 12mpg
294126
 

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Discussion Starter · #34 ·
Also check your oil level. Apparently these can not be over filled or it will damage the dpf. Check your vacuum pump for oil and check all vacuum hoses.
 

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Yes after 15,000 miles I came to find that the scr was clogged and collapsing in on itself. I just found this last week. During the beginning the only symptom, other than a plethora of codes that came up, was low performance. Particularly low boost.At first it was just a little low 220 kpa max). But just before I found it I was struggling to reach 170 kpa. My egt were running around 500c cruising.

The parts I changed were:
Map
Maf
Def injector
Egr
Nox 2
O2
Vacuum pump
Egt sensor 2
Turbo
Intake temp sensor
Accelerator pedal

Probably more. But this is all I can think of right now.

I did also have one more symptom which I didn't know was a symptom until I fixed it. The transmission was rough/ firm shifting both up and down. Now that it's fixed the shifting is actually on the mooshy side.

Pull up your desired boost pressure and also your actual boost pressure. And see if it is making the correct amount of boost. If it's not then you may have a restriction in your exhaust. Such as a plugged dpf or a plugged scr. To check the the scr I took loose the 3 bolts at the bottom of the downpipe to let excess pressure out. Took about 5 minutes and the increase in boost was immediate.

Now that it's fixed my egt are down around 330c
My coolant temp is down 20f
The trans shifts better
About 3 times the amount of torque
And I picked up 12mpg View attachment 294126

So I have had the firm shifting since i bought the car. I changed the fluid and the shifting was a lot better. I monitored the MAF on my way into work today and that seemed fine. I did notice my EGT #2 would climb kind of high when first reaching operating temp (850 F). I have a new one, just didn't have time or a reason to put it on yet. It creeps down within 75 degrees of the other two. I run all highway so my EGT's are all around 600 to 650 F. I do know that my SCR is not plugged. I have averaged 43mpg the entire time I have had this issue. I am considering putting a new MAF and 02 sensor in, but will definitely look into the vacuum pump and lines.
 

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Discussion Starter · #36 ·
So I have had the firm shifting since i bought the car. I changed the fluid and the shifting was a lot better. I monitored the MAF on my way into work today and that seemed fine. I did notice my EGT #2 would climb kind of high when first reaching operating temp (850 F). I have a new one, just didn't have time or a reason to put it on yet. It creeps down within 75 degrees of the other two. I run all highway so my EGT's are all around 600 to 650 F. I do know that my SCR is not plugged. I have averaged 43mpg the entire time I have had this issue. I am considering putting a new MAF and 02 sensor in, but will definitely look into the vacuum pump and lines.
Well 43 on a highway tank seems on the low side. I was getting 41-43 mpg the entire time I had it (13k miles). The last 2 tanks prior to fixing it were 40 and 38mpg. I have put 2 tanks through it now that it's fixed 51mpg and 49 mpg.

How do you know that your scr is not clogged?
Did you check your boost numbers?
Did you crack the exhaust loose and check for a change in performance?

I would find it unlikely, given the parts you have changed, that the problem is all the parts. Your treating the symptoms and not the actual problem. Which is what I did too until I found the scr. The good news is that once you do fix the core issue you can have peace of mind that these parts are all new lol

My car was slow, had low boost, had high egts. Now if I turn traction control off and punch it from a stop it'll smoke the tires. I have great power every where especially passing at highway speeds
 

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Well 43 on a highway tank seems on the low side. I was getting 41-43 mpg the entire time I had it (13k miles). The last 2 tanks prior to fixing it were 40 and 38mpg. I have put 2 tanks through it now that it's fixed 51mpg and 49 mpg.

How do you know that your scr is not clogged?
Did you check your boost numbers?
Did you crack the exhaust loose and check for a change in performance?

I would find it unlikely, given the parts you have changed, that the problem is all the parts. Your treating the symptoms and not the actual problem. Which is what I did too until I found the scr. The good news is that once you do fix the core issue you can have peace of mind that these parts are all new lol

My car was slow, had low boost, had high egts. Now if I turn traction control off and punch it from a stop it'll smoke the tires. I have great power every where especially passing at highway speeds

I had the SCR removed and cleaned. I just Forced a regen yesterday and all my nox readings were consistent. Boost readings were good. I'm not sure what is considered high for EGT. I have excellent power as well. What would the vacuum pump have to do with the performance? How does oil get into it and is there a seal I would change as well? I'm assuming I would change the solenoid as well?
 

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The vacuum pump not only provides vacuum for the brake boost, but it also provides vacuum for the turbo wastegate vane control and EGR Cooler. If you are having troubles with the vacuum pump, you will likely set a bunch of different codes like P003A, P24A5, P2598 and/or P2599. The vacuum pump is bolted to the driver's side of the engine and it driven by the forward camshaft. There isn't much that is serviceable on the vacuum pump, but I imagine if the drive seal is bad, it will draw oil in from the top of the head. A replacement pump is about $70. If it is leaking you will see oil around the outside of the pump. That doesn't mean that the pump is not working properly. Mine is leaking a little and needs replacement. The oil will get on the vacuum hoses underneath the pump and swell those hoses up, causing them to eventually leak.
 

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The vacuum pump not only provides vacuum for the brake boost, but it also provides vacuum for the turbo wastegate vane control and EGR Cooler. If you are having troubles with the vacuum pump, you will likely set a bunch of different codes like P003A, P24A5, P2598 and/or P2599. The vacuum pump is bolted to the driver's side of the engine and it driven by the forward camshaft. There isn't much that is serviceable on the vacuum pump, but I imagine if the drive seal is bad, it will draw oil in from the top of the head. A replacement pump is about $70. If it is leaking you will see oil around the outside of the pump. That doesn't mean that the pump is not working properly. Mine is leaking a little and needs replacement. The oil will get on the vacuum hoses underneath the pump and swell those hoses up, causing them to eventually leak.

Thank you, I have never gotten any of these codes. With 190k miles I change a lot of components as a precaution. I just need this thing to last me 3 years or 60k miles. I commute 400 miles/week and was tired of getting 15mpg in my Silverado!
 

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I commute in mine daily at that level as well, and when I lost my vanpool due to the pandemic, commuting in my 11 mpg square-body truck was definitely NOT going to cut it! I have averaged 43 mpg overall with 126k on my 2014 diesel cruze and today driving to work the 50 mile average reading on the dash was 50 mpg.
 
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