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2012 Terrain V6 engine or transmissions problems

64K views 77 replies 17 participants last post by  Jmtech22 
#1 ·
Hey all. I purchased a used 2012 V6 Terrain with 33,000 miles on it back in October. I have had it back to the GM dealer that sold it to me twice for what I describe a miss or maybe a Torque converter problem. When the vehicle reaches around 35-45 mph i get a shuttering affect like its either missing or the converter isn't locking up. Not sure what it is. Anyone else have this problem or maybe some suggerstions? The dealership replaced the coil and plug on the number 6 cylinder and they said it was fine but its not. Looking for answers or suggestions. Thanks
 
#3 ·
Dmax121 said:
Hey all. I purchased a used 2012 V6 Terrain with 33,000 miles on it back in October. I have had it back to the GM dealer that sold it to me twice for what I describe a miss or maybe a Torque converter problem. When the vehicle reaches around 35-45 mph i get a shuttering affect like its either missing or the converter isn't locking up. Not sure what it is. Anyone else have this problem or maybe some suggerstions? The dealership replaced the coil and plug on the number 6 cylinder and they said it was fine but its not. Looking for answers or suggestions. Thanks
Hey Dmax121,

Sorry to hear that your concern wasn't fully resolved by your dealership. As Rit suggested, definitely make them aware that the issue is still occurring. There is a chance that this issue may be covered by the parts warranty, and the dealership can correct whatever is causing problems in your vehicle. If you'd like our assistance with communicating your concerns with them, please message us your full contact information, VIN, mileage, and dealership name/location.

Thanks,

Amber N.
GMC Customer Care
 
#4 ·
I agree with Rit. Keep taking it back until they solve the issue. As far as I know it's not an issue that has been reported on this forum before or often. Best of luck and keep us posted. I own one of those models too so I'm very interested in your findings (and hopefully your solution.)
 
#5 ·
Dmax121 said:
Hey all. I purchased a used 2012 V6 Terrain with 33,000 miles on it back in October. I have had it back to the GM dealer that sold it to me twice for what I describe a miss or maybe a Torque converter problem. When the vehicle reaches around 35-45 mph i get a shuttering affect like its either missing or the converter isn't locking up. Not sure what it is. Anyone else have this problem or maybe some suggerstions? The dealership replaced the coil and plug on the number 6 cylinder and they said it was fine but its not. Looking for answers or suggestions. Thanks
I have the exact same thing happening with my 2012 Equinox with the 3.0 V6. I have had it to the dealership at least 5 or 6 times and every time they tell me that everything is ok. Here are the specifics of mine.

The issue is that you can feel a hesitation/miss that feels like a small "buck." I have narrowed down the circumstances of when it happens.

They are:

Speed: 30-50 mph
Gear: High gear
RPM: 1100-1500 rpm
Driving Condition: Under Load

When driving in the above ranges in high gear on flat ground it does not do it very often. As soon as you give it just a little bit of gas to slightly increase speed or simply hold the pedal in the same position while going up a slight incline, the engine is placed under load and it will do it 75% of the time. It does seem to get worse after driving for a few hours and getting everything heated up. If you press the gas down a little further or too much speed is lost on a hill, it will downshift and not happen again until it goes back into high gear and it is under load again.

I have had it into my dealer several times and they cannot find anything wrong. It has not thrown a code and is current on all software (ECM and Transmission) per dealer. They also test drove with their laptop connected and all fuel maps were perfect according to the service manager. They did complete a TSB that was similar to my symptoms regarding checking the camshaft sensor and putting dielectric grease on the connection. My symptoms did not change after the TSB service.

The last time I had the service manager ride with me, he had his laptop hooked up during our 30 minute ride. He felt the hesitation or "buck" several times and took snapshots of data in his computer when it happened so he could go back and look further into it. He then wondered if the problem wasn't with the TCC ?? (Torque Converter Control???) He overrode it while I was driving and locked it in and then locked it out. I cannot remember which way it occurred but one way made the situation dramatically worse and the symptom was displayed nonstop. I called him a few days after the ride to see what he found in the snapshots and he said nothing showed up and all fuel trims and data were normal. At that point he said there wasn't anything else he could do until it either throws a code or the symptom gets worse. It is frustrating that along with advances in technology comes reliance on technology and inability to diagnose and solve problems. Everyone wants to hook vehicles to a computer to diagnose issues and if it tells them everything is ok they cannot do anything even though they have felt the issue and know there is something mechanically wrong.

Let me know if you find the culprit as I currently have about 35,000 miles left on my 100,000 mile warranty. As much as I drive, it will be out of warranty this year!
 
#6 ·
OverRHeads said:
I have the exact same thing happening with my 2012 Equinox with the 3.0 V6. I have had it to the dealership at least 5 or 6 times and every time they tell me that everything is ok. Here are the specifics of mine.

The issue is that you can feel a hesitation/miss that feels like a small "buck." I have narrowed down the circumstances of when it happens.

They are:

Speed: 30-50 mph
Gear: High gear
RPM: 1100-1500 rpm
Driving Condition: Under Load

When driving in the above ranges in high gear on flat ground it does not do it very often. As soon as you give it just a little bit of gas to slightly increase speed or simply hold the pedal in the same position while going up a slight incline, the engine is placed under load and it will do it 75% of the time. It does seem to get worse after driving for a few hours and getting everything heated up. If you press the gas down a little further or too much speed is lost on a hill, it will downshift and not happen again until it goes back into high gear and it is under load again.

I have had it into my dealer several times and they cannot find anything wrong. It has not thrown a code and is current on all software (ECM and Transmission) per dealer. They also test drove with their laptop connected and all fuel maps were perfect according to the service manager. They did complete a TSB that was similar to my symptoms regarding checking the camshaft sensor and putting dielectric grease on the connection. My symptoms did not change after the TSB service.

The last time I had the service manager ride with me, he had his laptop hooked up during our 30 minute ride. He felt the hesitation or "buck" several times and took snapshots of data in his computer when it happened so he could go back and look further into it. He then wondered if the problem wasn't with the TCC ?? (Torque Converter Control???) He overrode it while I was driving and locked it in and then locked it out. I cannot remember which way it occurred but one way made the situation dramatically worse and the symptom was displayed nonstop. I called him a few days after the ride to see what he found in the snapshots and he said nothing showed up and all fuel trims and data were normal. At that point he said there wasn't anything else he could do until it either throws a code or the symptom gets worse. It is frustrating that along with advances in technology comes reliance on technology and inability to diagnose and solve problems. Everyone wants to hook vehicles to a computer to diagnose issues and if it tells them everything is ok they cannot do anything even though they have felt the issue and know there is something mechanically wrong.

Let me know if you find the culprit as I currently have about 35,000 miles left on my 100,000 mile warranty. As much as I drive, it will be out of warranty this year!
Sounds like what my 2012 3.0 nox was doing! They ended up being misfires. When I hooked up my laptop I could read the misfire counter and 2 of the cylinders had dramatically higher counts than the other 4. It was improved but not mitigated by a TSB the dealer preformed which included a "fuel system cleaner" soak for a few hours to decarbon the engine. It wasn't enough misfires to throw a code but enough to feel and be annoying. Try going in complaining of a rogue misfire instead of a tcc problem.


Sent from my bragging iPhone using an app that encourages it.
 
#7 ·
austin said:
Sounds like what my 2012 3.0 nox was doing! They ended up being misfires. When I hooked up my laptop I could read the misfire counter and 2 of the cylinders had dramatically higher counts than the other 4. It was improved but not mitigated by a TSB the dealer preformed which included a "fuel system cleaner" soak for a few hours to decarbon the engine. It wasn't enough misfires to throw a code but enough to feel and be annoying. Try going in complaining of a rogue misfire instead of a tcc problem.
That is great info! I remembered after reading your post that my dealer did try a decarbon TSB at one point but it did not solve the problem. I guess it may have gotten a little better for a very short time but did not fix it. As far as the misfires showing up on the computer. Wouldn't that have jumped out at my service manager when he rode with me with his laptop hooked up? Do you think the carbon is causing the misfire? Do you think the carbon is from the notorious oil into the intake issue? I don't have a catch can installed.
 
#8 ·
OverRHeads said:
That is great info! I remembered after reading your post that my dealer did try a decarbon TSB at one point but it did not solve the problem. I guess it may have gotten a little better for a very short time but did not fix it. As far as the misfires showing up on the computer. Wouldn't that have jumped out at my service manager when he rode with me with his laptop hooked up? Do you think the carbon is causing the misfire? Do you think the carbon is from the notorious oil into the intake issue? I don't have a catch can installed.
Yeah it did improve after they did the work but it didn't solve it. I took it back to see if they'd do it again for me but they said they bent the rules doing it in the first place as there was no CEL. I don't know why that didn't jump out at the tech on the ride. Maybe he just wasn't looking for them? And I do believe the carbon probably came from not having a catch can. DI engines are known for this...one of the few downsides. It could also be the coil packs I suppose. I know the traverses had a notorious coil pack issue. Seemed like the same symptoms. I believe Rbarrios could tell you more about that.


Sent from my bragging iPhone using an app that encourages it.
 
#10 ·
Iliketerrain said:
I have a '12 Terrain 3.0 V6 AWD and I have the same symptoms. In light loads
up a hill at 1500 rpm it bucks. This summer when the weather isn't 20 or below
I'll put the computer and see if I'm having misfires.
What software/hardware do you use, and where did you get it ?

THX
 
#11 ·
Thanks for all the info guys. This is exactly what i am experiencing. They did replace the coil and plug on the #6 cylinder but to no avail. Its like a hesitation or a miss. Kinda jerks back and forth between 35-50. Also I have watched the tach and it bounces around just a little. I am gonna take it back again and if its not fixed i'll contact GM and also repond on here with my info. Thanks for all the replys. Keep them coming especially if anyone resolves the issue!
 
#13 ·
Going to the dealership in the morning and leaving my 12 Terrain to have them check out this problem for the second time. I had the service manager ride with me and he felt several times what seems to be a misfire. They are giving me a car to drive till they find the problem. He did state that the 3.0 engine which is used in older Acadias tend to have a know problem with the coils. They replaced the coil and sparkplug on cylinder #6 a little while ago and it didn't help. I guess we will find out. The service manager also said the problem might have to get worse before it shows up on the computer. At least they are trying to solve it. :beer:
 
#14 ·
Well got my Terrain back and guess what? They couldn't find anything wrong with it. The service advisor said the mechanic drove it and had it hooked up to the laptop and no codes or misfires showed up. Its gotta be something. Told the service advisor about the posts on here and he said there is nothing they can do till a code shows up. What ever happened to using your brain and not a computer? I have a call in to the actual Service Manager. I went to all the inconvience of going to the garage, unloading what I needed to a loaner vehicle, taking it back. All on a day off where I had alot of other things to do. So pissed right now. When the guy rode with me he felt what it was doing and said theres a problem somewhere. Now they say just hope it gets worse so something..or should I say a code shows up. What should my next step be? I need some advice here.
 
#15 ·
some dealers have a device--
that is plugged into the car..

when the vehicle begins to act up... you press a button to records engine/computer parameters that may aid in diagnosing whats going on.
 
#16 ·
Related to rbarrios's suggestion - I use the TorquePro Android app with a bluetooth scanner. Within the app, I asked for a log file to track my voltages as I was trying to troubleshoot my pulsing lights.

Don't know if you have a OBD scanner, but it might be incredibly helpful here. My scanner was >$100, expensive, but likely cheaper than any repair bill you'll see if this problem persists beyond your warranty period. Just a thought. And there are cheaper scanners, but I don't know how quick their read times are. The app was a cheap $5.

And this set up would work with practically any other OBD II vehicle made since 1996 (buy it once, you're good for many years down the road).
 
#17 ·
Update..... They did hook up my Terrain to their laptop as they drove. Everything was within normal limits. But with that said they felt the jerk, hesitation, miss what ever you wanna call it. Gonna replace my torque converted and a few other parts. The service department has been great to work with. I bought my Terrain used with 34,000 miles on it. Good thing was it is a. Certified GM vehicle which gives it another 30,000 mile or two year warranty. He promised me that they will get it fixed. Giving me Buick Enclave to drive again. My wife loved it. I admit it was sweet but love the size of the Terrain. GM told him that they had a few complaints about the same problem. Any suggestions?
 
#18 ·
Transmission

One of the things I have taught my wife over the years is to come to a COMPLETE stop in going from reverse into drive and vise versa. Rolling switching into these gears is hard on transmissions. IMO of course.
 
#19 ·
Gotta say my wife is a very good driver. She does not speed and does come to a complete stop before going from reverse to drive. She's really easy on a vehicle. That's why when we traded her 2008 Civic in They gave us a fantastic trade. Sold it within three days. The sales manager ask if anyone had ever stepped on the carpet. My answer was no. Lol had the all season mats. We both baby our vehicles. It's your second biggest investment besides your home.
 
#20 ·
Dmax121 said:
It's your second biggest investment besides your home.
Well, for some of us our retirement is our biggest investment. Then the house. Then the cars...
 
#22 ·
UPDATE.... I am taking the Terrain in tomorrow for a torque converter changeout and something else but not sure. They are giving me a Enclave to drive. I gotta say the Service Manager at the dealership I bought it from is really trying to figure out what is going on. He said we will start with this and then if it doesn't work we will do something else. He actually felt it several times when he did the ride along. The laptop they had hooked up while driving showed everything normal but as we know something is wrong somewhere. Not sure if its an engine miss, torque converter or what although the computer says no. I love the vehicle but even my wife, who drives it most of the time is starting to complain about it. I'll let everyyone know the outcome after we drive it for a while.
 
#24 ·
Dmax121 said:
What are they telling you OverRHeads ?
I have not taken mine to the dealer for a while. The service manager doesn't seem as proactive as yours to try things and figure out the issue. He refers to the fact that there are not codes being thrown and the laptop and freeze frames showed that everything was normal when the symptom occurred. His best suggestion was that he would check for engine ecm or transmission control updates when I brought it in for oil changes, etc. I am not satisfied with this answer but, until I have something else to go on, I am in a "wait for a code" pattern. :banghead: :thumbdown:

I have great hopes that your service manager will find the culprit and I can go to my dealer and let them know that I have the answer to the problem that they should have been able to find!!!!!
 
#25 ·
Dropped the Terrain off this morning and I had a brand spankin new Enclave waiting on me. The service manager said it should be done by Friday. He's very supportive and proactive. We will see what happens in the end. That's why I like the smaller dealerships. They tend to take things more serious than just getting you I and out. Just my opinion. :beer:
 
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