[ADubH]

Check engine light came on again in my 2012 Terrain.

Onstar diagnosed as part of the emissions system not working as expected. I made a service appointment for this Saturday with the dealer. Anyone else had this issue?


Previous: 1999 Chevy Lumina Base

Current: 2012 GMC Terrain SLT2 AWD V6
20 mpg average

 

[rbarrios]

if it was a loose gas cap- im sure Onstar would have told you to check the gas cap.
But let us know what it is.

 

[Chevrolet Customer Svc]

Please keep me posted on what you find at the dealer. Feel free to contact me if you have further questions. Thank you.

Tricia, GM Customer Service.

 

[ADubH]

Bad EGR valve. Driving a Buick LaCrosse while they order the part and fix it.


Previous: 1999 Chevy Lumina Base

Current: 2012 GMC Terrain SLT2 AWD V6
20 mpg average

 

[kparrent]

Bad EGR valve. Driving a Buick LaCrosse while they order the part and fix it.


Previous: 1999 Chevy Lumina Base

Current: 2012 GMC Terrain SLT2 AWD V6
20 mpg average

Bad EGR already? Did they say what was wrong with it? How many miles do you have on it?

 

[ADubH]

They didn't say what was wrong, just that it needed to be replaced. I have about 4700 miles on mine. Had it right under 5 months.

 

[kparrent]

They didn't say what was wrong, just that it needed to be replaced. I have about 4700 miles on mine. Had it right under 5 months.

Hopefully it was just electrical or something. I would hate to be seeing the valves failing or being clogged already.

 

[ADubH]

Hopefully it was just electrical or something. I would hate to be seeing the valves failing or being clogged already.

No kidding. Hopefully this is the only problem for a while besides regular maintenance.


2012 GMC Terrain SLT2 Carbon Black/Gray interior

 

[ADubH]

Haven't heard anything today. Dealer expected to have it until Wednesday so hopefully I get it back tomorrow. Guess we will see.


2012 GMC Terrain SLT2 Carbon Black/Gray interior

 

[ADubH]

The part is stuck in customs in Canada. Dealer says 4-7 days possibly. At least I have the loaner to drive.


2012 GMC Terrain SLT2 Carbon Black/Gray interior

 

[ADubH]

Called dealer today. Part came in but was damaged. Should have another one tomorrow and will hopefully get my Terrain back.

With my luck that part will get stuck in customs too.


2012 GMC Terrain SLT2 Carbon Black/Gray interior

 

[ADubH]

Finally got my Terrain back! Getting better gas mileage and everything. It's back to 20 mpg!


2012 GMC Terrain SLT2 Carbon Black/Gray interior

 

[robotpepper]

I've had my engine light come on at least three times so far this winter in southern Ontario (and it's a very mild winter at that). Each time it came on soon after a "cold" start-up (I usually let it warm up for 30-60 seconds then drive it very easily until it's fully warmed up). I've called OnStar about it and they always said it was a temporary air/fuel ratio issue (but nothing ever noticeable to me). The adviser said it was a temporary issue and everything looked fine to them each time when they did their system scans, that the light should go out shortly or after a couple days and if it didn't then to take it to the dealer.
It's a 2011 SLE-2 I4 with ~50,000km on it and a K&N CAI put on shortly after getting it (I think around 12,000km). Thought it may have been from the CAI but I had that on last winter (which was much colder) and it never happened to me then. Ideas?

 

[Wkeatonjr]

I've had my engine light come on at least three times so far this winter in southern Ontario (and it's a very mild winter at that). Each time it came on soon after a "cold" start-up (I usually let it warm up for 30-60 seconds then drive it very easily until it's fully warmed up). I've called OnStar about it and they always said it was a temporary air/fuel ratio issue (but nothing ever noticeable to me). The adviser said it was a temporary issue and everything looked fine to them each time when they did their system scans, that the light should go out shortly or after a couple days and if it didn't then to take it to the dealer.
It's a 2011 SLE-2 I4 with ~50,000km on it and a K&N CAI put on shortly after getting it (I think around 12,000km). Thought it may have been from the CAI but I had that on last winter (which was much colder) and it never happened to me then. Ideas?

If I suspected the CAI, I would remove it and put my stock airflow back in to test that theory.

 

[robotpepper]

If I suspected the CAI, I would remove it and put my stock airflow back in to test that theory.

Of course, but the problem is very intermittent and conditions/environment are never the same. The weather was different, driving style (for one of the episodes) was different, the fact it never happened last year despite it being even colder... leads me to believe it isn't the CAI, or the problem would be much more frequent and/or even constant (I think, anyway...) wondering what else could cause this though - too many variables and won't be able to replicate it for the dealer. ah well.

 

[Wkeatonjr]

Of course, but the problem is very intermittent and conditions/environment are never the same. The weather was different, driving style (for one of the episodes) was different, the fact it never happened last year despite it being even colder... leads me to believe it isn't the CAI, or the problem would be much more frequent and/or even constant (I think, anyway...) wondering what else could cause this though - too many variables and won't be able to replicate it for the dealer. ah well.

My first thought is a MAF (Mass air flow) sensor going bad.

 

[RIT333]

My first thought is a MAF (Mass air flow) sensor going bad.

Or, the MAF is getting oily from the CAI. Have you tried cleaning the MAF ?

 

[CuHead]

Of course, but the problem is very intermittent and conditions/environment are never the same. The weather was different, driving style (for one of the episodes) was different, the fact it never happened last year despite it being even colder... leads me to believe it isn't the CAI, or the problem would be much more frequent and/or even constant (I think, anyway...) wondering what else could cause this though - too many variables and won't be able to replicate it for the dealer. ah well.

did onStar give you the code? had P0171 (too lean) with K&N CAI anytime after cold start when it was less than about -10C. It has been a rather warm winter here, so have only had a few days at this temp. Swapped the factory intake back in and code has not reappeared.

 

[Wkeatonjr]

Or, the MAF is getting oily from the CAI. Have you tried cleaning the MAF ?

Very possible. I used to have to soak the MAF on my VW in alcohol overnight to clear the check engine lights once in a while.

 

[robotpepper]

Or, the MAF is getting oily from the CAI. Have you tried cleaning the MAF ?

That occurred to me but it's an oil-free CAI from what I understand... the light always goes away after a day or two with no adverse effect on performance. If it continues I'll put the stock intake back on.