2010 Terrain - weird issues...

Was cruising along last night, 45mph or so. Approaching a red light, I let off the throttle, when out of the blue, the engine starts to shudder, and a message comes up on the communication panel "Reduced Engine Power". I have no idea what that means...so I pull over, shut the car down, and start Googling.

There's mixed info out there...likely because its still a newish vehicle. I read some forum posts talking about fuel pump issues due to the fact that direct injection requires insane fuel resure, and possible TSB's regarding other fuel system problems or excessive carbon buildup on sensors in the throttle body...but nothing conclusive.

After not getting anywhere online, I called the dealership. its 3pm on a Saturday, so of course there's no one in the service shop available. The blonde dingbat answering the phone has no idea what a fuel pump does. The car is still under power train warranty, temp was fine, oil level on the dipstick is fine, so I decide to limp up to the dealership about 15 min away.

Start the car up, and its as if nothing was wrong. Error messages are gone, cars idling normally, just the small check engine light is on. So get the car to the dealer, and out of luck, the salesman I bought the car from is working this weekend. He mentioned that onstar will run a self diagnostic at any time, and may be able to shed some insight on what's up.

On star girl is only slightly more care knowledgeable that the dealership girl, and can't really tell me exactly what's wrong except that theres a "critical engine failure", code P3725, and that I need to shut the engine off immediately.

Long shot, anyone have any insight into this code or had a recent situation with a newer GM 3 liter V6? I'm guessing if its a fuel system issue, powertrain warranty won't cover this. We need this car to last another 5 years or so, which means I will likely have a pro cover the repair (though likely not the dealer). If there are TSB's out for this issue, maybe the dealer will work with us on this, though I'm not holding my breath.

Google search turns up nothing about that code in any context with any car. I wonder if its a unique OnStar code or something.

yeah...that's the problem I'm having. There's next to no info out there. I guess there must not be a lot of Terrain enthusiasts out there.

Isn't it the same as the Acadia? The "P" warning codes generally carry over thoughout an entire line. A P0171 code is the same on a Honda and a Ford.....

I think whomever told you that code, told it to you wrong.

P0xx codes are govt set. P1xx on up are manufacturer specific. Only thing is the p0700 codes are variable to cover different transmission possibilities.

That being said it could be a multitude of problems on that specific code.

OK, so I got an update - ish. Code was P2135 - this is a Throttle Position Sensor disagreement error. Basically, there are 2 TPS in the LF1 3 liter V6. If the 2 disagree by a wide enough margin over a long enough period of time, then the engine cuts into limp mode, the "Reduced Engine Power" code is displayed, and traction control is turned off.

From what Ive read, once the engine is shut off, after 30 seconds, a restart will clear the Reduced Power setting, and TCS/Stabilitrack will be reinstated, though the CES light will remain illuminated, and the P2135 code is retained.

I found a TSB: http://engine-codes.com/uploads/gmc/11-06-04-0007B.pdf related to GM vehicles, though neither the Terrain, or the LF1 engine are mentioned. A little more forum searching revealed mixed info regarding the P2135 code in Terrains. Some users mentioned having the TPS repair/replacement covered under the 100k powertrain warranty, others not. Im not having any luck finding any 2010 GM Powertrain warranty info on teh googelz, so Im not sure if the TPS is covered or not, though considering its part of the throttle body which governs the main component of the powertrain (i.e. the engine), Im not sure how it could not be covered (dealer/MFR hi-jinx can be ...silly, though).

If anyone can steer me towards any online GM warranty resources that lay out any specifics of whats covered and whats not, that would be a huge help.

Bueller?

slap a carb on it

short version...P2135 error code is caused by carbon buildup in the throttle body.

V8 motors: covered under special coverages in the 100k powertrain warranty.
V6 motors: GM sez go berk yourself.

$500+ to replace a TPS...wait, can't replace the TPS on its own...carbon buildup means whole new overengineered throttle body.

whiskey tango foxtrot? Seriously, what the hell is up with that? Why is every 08-current V8 covered, but the exact same part having the exact same issue in the V6 is not? Perhaps there are more sixes in the wild, and they don't want to cover the cost? dunno, buy I'm feeling betrayed.

Wife: Currently drives a purchased new Terrain. Before that, a purchased new Ion. Before that, a purchased new Cavalier.

Mom: Currently drives a purchased new Malibu. Before that, a purchased new Century.

Dad, currently drives a Colorado, before that, a Malibu

Sister: Cobalt

Father in law: Purchased new Silverado. Also owns a C6 'vette

His girlfriend: a purchased new Trailblazer.

Where is GMs loyalty to a loyal family? I'm pro GM...always chatting up the Regal, was...WAS looking at a new Eco Cruze when my 99 179k daily Infiniti finally takes a crap (currently running on its factory TPS btw...cable throttle ftmfw).

maybe I'm gonna rethink that last part...

What about pulling off the t-body and cleaning it? The Supercharged Cobalts had an idle issue that went away with a good blast of cleaner.

Was it cold and snowy? Like really cold, not Florida cold? Its really common for the throttle bodies to ice up a bit, and the plate doesn't shut as quickly as the computer thinks it should, so it shuts it off and attempts to regulate rpm by cutting cylinders.

I fight that on my Volvo whenever I've been on the highway with snow. Next day, I curse it until I can get it in a warm place for a while.

If you live in warmland, clean the throttle body.

Have you called the dealer to find out what your warranty and coverage is?

Yep, been talking to the dealership, they arent budging. Told the guy I intended to call GM customer service, and he basically dared me to. Told me that GM would just call him to find out whats wrong, and then GM would tell me there was no coverage anyway, so in his words "what would be the point in the end?".

I plan to call GM anyway. In general I want to ask why the exact same issue with the exact same trouble code with the exact same component is covered under special coverage for the V8, and not the V6. Thats asinine. THe throttle body is crippling my powertrain, is connected to the powertrain, governs the powertrain, but is not covered under the powertrain warranty?

This is also happening to my not even 4 year old car. One thats been in to this dealership for 4 other warranty claims all covered under the bumper to bumper (suspension issues, and some kind of exhaust solenoid issue). Now that I have an issue outside of that 3 year 36k b2b warranty, Im being told to take a hike? This is my wifes 3rd new GM car in her lifetime. Unless GM wants this to be her last, they need to work with me on this.

I'd call GM customer service. I'd explain how loyal a customer you are, and I think they're in a tough spot to defend when the same part is covered when it's in front of a V8. Not that they have to do anything, but if I were them I would consider it. Mention that you're also influential in the purchase of new cars in your family, and give them the list of purchases. Also mention the other quality issues you've had with the car and say that you're very disappointed with GM.

By the terms of the warranty (see below), they're not obligated to do anything. Keep that in mind, and attack them from the "I'm a loyal customer, please do the right thing" angle, not the "you have to do this" angle.

Here's the coverage list: http://www.gmc.com/owners/warranty.html

GM said: Engine: Cylinder head, block, timing gears, timing chain, timing cover, oil pump/oil pump housing, OHC carriers, valve covers, oil pan, seals, gaskets, turbocharger, supercharger and all internal lubricated parts as well as manifolds, flywheel, water pump, harmonic balancer and engine mount. Timing belts are covered until the first scheduled maintenance interval. Exclusions: Excluded from the powertrain coverage are sensors, wiring, connectors, engine radiator, coolant hoses, coolant, and heater core. Coverage on the engine cooling system begins at the inlet to the water pump and ends with the thermostat housing and/or outlet that attaches to the return hose. Also excluded is the starter motor, entire pressurized fuel system (in-tank fuel pump, pressure lines, fuel rail(s), regulator, injectors, and return line) as well as the Engine/Powertrain Control Module and/or module programming.

Datsun1500 wrote: http://www.gmc.com/owners/warranty.html That shows what is covered. If it's not there, don't expect GM to override the dealer. It specifically excludes the fuel system, but does not mention the throttle body by name. Can it be cleaned?

2 things:

• I dont necessarily expect GM to override the dealer...but, I do expect them to authorize the dealer to perform the repair and then reimburse the dealer under my warranty. The dealer already said they tried to find any possible way to do the repair under warranty so I wouldnt have to pay for it, theres just nothing there covering my vehicle. I do know that GM is covering this exact repair for other vehicles (same part, same issue, same trouble code, same repair procedure - TB replacement).

• It can be cleaned: http://engine-codes.com/uploads/gmc/11-06-04-0007B.pdf . Provided its the same actual TB part number, the official GM TSB for this procedure is in that link. I probably could do it myself, but the thing is I shouldnt have to.

Still trying to get into contact with GM. If worse comes to worse, THIS GM LETTER SENT TO OWNERS OF V8 VEHICLES explains how GM plans to cover this repair for their engines. That letter was written by Jim Moloney - "General Director, Customer & Relationship Services (CARS) at General Motors", as listed by his LinkedIn profile. I could contact him directly thru linkedin, tell him how confused I am that this issue is not covered for me, but is for other owners, let him know that as a loyal GM family, how disappointed I am that there doesnt seem to be any loyalty back, and see what he says about all that... though I would prefer to avoid guerrilla tactics.

...for now

You seem to have valid questions requiring answers find the answers here CUSTOMER ASSISTANCE CENTER 1-800-462-8782 Also you might want to try another dealership

So, apparently, GM customer service wants me to believe that $500+ throttle bodies are wear items. I explained that of all the cars Ive ever owned, or that on any of the cars anyone I ever knew has owned, Ive never had to or heard of anyone else having to replace a throttle body. Sensors? Yes, TPS sensors can wear out. But not the entire assembly, especailly after only 70k miles, especially on cars not even 4 years old. Throttle bodies are not wear items.

The lady on the phone tried to explain to me that she has no idea why certain models have certain coverages, and others dont. I guess I can understand that she specifically doesnt know. She explained that coverages take into account things like the way a vehcilc is assembled, how the engine is built, what factories do the assembly, and several other factors.

She also said my particular driving style may be to blame. I must drive exactly the same as millions upon millions of other drivers, some of which are being covered. I fail to see how the factory that did the assembly can affect how carbon builds up in the motor. I fail to see how my drivng style - the style which (supposedly) leads to the error - somehow precludes me from coverage, while the style of V8 drivers keeps them in the fold.

Im trying to speak with someone higher than the nice phone lady Ive been talking to thus far, but am meeting resistance. She got a little excited when I started mentioning TSB numbers and the document ID for the letter mentioned previously. I guess time will tell.

Theyre "checking into my situation" and are going to call me back. Maybe I should draft an email to Mr. Jim Moloney, just to be on the safe side.

(also hoping that mentioning Jim Moloney enough times may trigger GMs social media peoples search engines, get them to take a look at this thread, and maybe get things moving along a little faster...)

2010 GMC Terrain SLT2, LF1, P2135 Jim Moloney

2010 GMC Terrain SLT2, LF1, P2135 Jim Moloney

2010 GMC Terrain SLT2, LF1, P2135 Jim Moloney

2010 GMC Terrain SLT2, LF1, P2135 Jim Moloney

2010 GMC Terrain SLT2, LF1, P2135 Jim Moloney

Social media may be your fastest route to resolution. Don't trash them, just go on something like Facebook and say you have some questions regarding the powertrain warranty coverage. Usually the social media channels are more adept at bringing the issues to resolution than the older channels (i.e. phone, email).

Who states whats covered in the warranty? GM? The Dealer? Im under the impression its GM. I want this problem, which has been corrected, at no cost, using special provisions made under the GM powertrain warranty, for other GM owners, to be corrected for me, also a GM owner, in the same way. Plain and simple.

Though I agree on the making myself crazy part...If GM is comfortable severing loyalties that span 3 generations over this, then I guess I am too.

I would clean it. Then, draft a polite, concise letter to someone as far up the chain as you can - and tell them your history, story and specific issue.

Then I'd forget all about it until they contact you. If it never happens or you need another car before that - maybe don't look in the same place again.

I guess I just dont understand why excessive carbon buildup is covered for the V8, and not the V6. Perhaps I will never know. But crap like this is why, when my 99 Infiniti finally breaks down, as much as I tout the new turbo regal and eco cruze, I really want to replace it with another used car from the 90s, probably japanese.

I just cant fathom a scenario where a throttle body should need to be REPLACED in under 4 years, let alone out of my pocket. Ive been struggling internally to keep my faith in GM. This isnt helping them win the war over my wallet.

Youch, don't have much to add other than the eco cruze is a great commuter. If you do go that way, grab it used, the 6spd manual depreciates like mad. That was one of the best transmissions I've shifted, long throws, but always very direct and positive.

Crazy to me that w/ 70k miles they're trying to claim it's on you....

Well, just got off the phone with GM, they told me to berk myself in a corner. I told them how disappointed I was, and how, as a long time, repeat customer, from a family of repeat customers, I will be seriously rethinking my future car purchases. GM girl didnt seem to give a flying berkeley. She sounded like a damned robot, "The part is considered by GM to be a wear and tear item". Serpentine belts and brake pads are wear and tear items, not precision machined complex mechanical components like a computer controlled throttle body.

Giant Purple Snorklewacker wrote: I would clean it. Then, draft a polite, concise letter to someone as far up the chain as you can - and tell them your history, story and specific issue. Then I'd forget all about it until they contact you. If it never happens or you need another car before that - maybe don't look in the same place again.

Like I said, Id bet Jim Moloney - General Director, Customer & Relationship Services (CARS) at General Motors:

http://www.linkedin.com/pub/jim-moloney/4/a23/978

is pretty high up...

I'd point out how disappointed I am over the fact that one of The Big Three can't make a throttle body that last more than 3 years when the rest of the world figured out throttle bodies that lasted forever somewhere in the 70s.