Car sputters and hard to crank on a cold start.
 

Hello everyone. I have a 2011 HHR with only 32000 miles. My car is sputtering after cranking it only on a cold start. My check engine light is also on and the error code is (P 0172). When I took it to the dealership for a diagnosis, they tell me that the fuel trim is rich and that my alcohol content from the gasoline I'm using is very high, over 65% and that is what's causing my car to sputter on a cold start and my check engine light to come on. Of course that kind of problem want be covered under the manufacturers warranty.

They claim in order to fix the problem, they would need to clean the fuel injectors and the throttle body. After cleaning all of that the computer would have to be programmed also. I'm sorry but that sounds like a bunch of bull and I'm not believing that story without seeking a second opinion first.

Has anyone ever had this kind of problem?

A few people have had the same code pop up. Did you use the Search Tool at the top of the page to search for p0172? One that I just read mentioned that they cleaned the MAF sensor and the problem cleared.
https://www.chevyhhr.net/forums/problems-service-repairs-42/more-cel-p0172-44575/

Did you fuel up with e85 instead of regular gas? Is your car e85 capable?

X2.....

before allowing the dealer to proceed I would use up as much of the fuel, that is in the tank, as possible and refill with a name brand making sure it is AT LEAST 87 octane then use Seafoam, or similar product. Might be required to do this a couple of times to get acceptable results. And of course do as suggested above.

Look at the threads that are listed for your problem in the "Search" field.

Of course you may also have a fuel pressure problem, which creates additional service.

Do you know how the dealer determined that your current fuel is 65% alcohol?

Check your PM, and sorry for the late reply.

To me it sounds like a dealer that's bypassing the proper diagnostic procedures and going for your wallet with the classic "upsell" of a "Fuel System Service".

To me, the first step is always suspecting a dirty, failed, or loose MAF sensor.

http://www.obd-codes.com/p0172

A. they can tell the alcohol % with a scanner.
B. P0172 Can mean: bad O2 sensor, exhaust leak, bad catalytic converter, broken flex pipe among other things.
C. Pretty amazing that a GM dealer would leave it at that. An OBDII code is the STARTING point in a diagnostic not the end.

donbrew....

I know what the procedure is (by the way, they also use a litmus paper test and compare it to a color chart). I want to know if the dealer did that or guessed. Seems like an unusual number, but I guess it would depend on the mixture proportions.

But I doubt even "if" he used any mixture ratio it would cause the symptoms he is expressing.....unless used for a long period of time AND the mixture did cause some corroding effect.

Sorry, I didn't see the "do you know" part of the sentence. :red:

And, it would only apply to FlexFuel vehicle anyway. It's a 2011 so it is.

The other way would be a refractometer (however it is spelled).

But it doesn't sound like the "dealer" spent much time on it.

Thanks for replying. Yes my car is E85 capable and I always use regular gas that is 87% percent octane rated and I always get gas from the same gas station. I will be sure to check the MAF sensor to see if its working properly.
When I typed in the error code in the search tool it didnt give me any results. But thanks for pasting the link so I can find it...

Thanks for the info. I will do as suggested. No I don't know how the dealer determined the alcohol content in my gasoline. Apparently they must have some kind of device that they can connect to my fuel rail to get a sample.

Wow I had no idea that code could mean all of those things. The dealer didn't mention any of those possibilities, I guess not all GM dealers are created equally.
Yes I totally agree that an OBDII code is the STARTING point in any diagnostic, but it should definitely point you in the right direction in troubleshooting a problem. But my next step is too seek out another dealership for a second opinion for sure.

Thanks for your input and for replying to my thread.

The OBDII reports the alcohol % to a TechII scanner and many other scan tools, not all. My ScanmasterELM software and my $12 bluetooth adapter does.

If you are not buying E85 on purpose, I might be suspecting the sensor in the gas tank, I think it's part of the fuel pump.

When I put "P0172" into the search box 8 pages of results spit out.

The computer reports the alcohol content to the OBDII reader. There is a sensor in the gas tank, part of the fuel pump IIRC. If you are not putting E85 in the tank, maybe the sensor has gone wonky.

The OBDII code is supposed to tell the technician where to turn his book to start further testing. All too many of them got their training at Advance AutoZone PEP as a tool to sell parts. We have been hearing a lot of people lately getting caught in the "throw parts at it until goes away" tornado, it surprises me that it's Official GM shops doing it.

Hey, I think I missed something......

If your car is E85 certified how is the 65% alcohol to high and affecting the performance? E85 is 85% alcohol.....no???

I think that the basic issue is a dealer or dealer's tech who isn't versed in the proper diagnostic procedures, coupled with the typical service department "upsell" mentality.

Now if there is really that much alcohol in the fuel, and as the OP stated, he doesn't use E-85....then the gas station may have a tank filled with the wrong juice.

That can happen, not too long ago a local gas station got their tank filled with diesel accidentally, around 100 cars had to be fixed on their dime.

[QUOTE=843de;726103]Check your PM, and sorry for the late reply.

To me it sounds like a dealer that's bypassing the proper diagnostic procedures and going for your wallet with the classic "upsell" of a "Fuel System Service".

To me, the first step is always suspecting a dirty, failed, or loose MAF sensor.

http://www.obd-codes.com/p0172[/QUOTE

Please pardon my ignorance but where is the MAF sensor located?

(Check out post #18 below....843de)

No I have never used E85 gas. I have always used regular gas that's 87 octane rated or higher. Well if it is the sensor in the gas tank that should be a covered repair under the manufacturers warranty hopefully.

I found the results for the code in the search engine thanks. I had a typo in my search which threw everything off. Yes I too am very surprised at the poor troubleshooting abilities of these GM mechanics but I think its just this particular GM shop. There are a few others in my area so I will be giving them a visit.

The MAF sensor is part #14 in this diagram, it's easy to get at once you've removed the airbox. It should only be cleaned using "MAF Sensor Cleaner" available at your local auto parts store.

One important thing to remember, DO NOT under any circumstances touch the sensor elements, just let the cleaner blast away any deposits. If you touch the sensor elements, it's pretty much ruined.

http://parts.nalleygmc.com/images/pa...231T03-003.JPG

ooooo I like that picture. Downloaded for future reference.

Easy to understand, gets the job done, and suitable for framing. What more could you ask for?;)

Thanks for the diagram! That was just what I needed!:thumb::thumb::

Ok after taking my car to several local mechanics they all agreed that it was the MAF sensor that was bad, but this is the problem I am running into now. You specifically stated and others have also that "One important thing to remember, DO NOT under any circumstances touch the sensor elements, just let the cleaner blast away any deposits. If you touch the sensor elements, it's pretty much ruined.. I have went to several local part stores to buy the part and they all come in a box UNSEALED. How do I know if the part has been touched or mishandled if its not sealed in plastic! I cannot believe that the manufacturer would ship the part like that knowing how sensitivie it is. I dont trust buying a part like that if it isn't sealed. What can I do or am I just over reacting a little bit?

Personally, I've never run across a replacement MAF sensor in a shrink wrapped box, this includes one right off the dealer's shelves.

If you buy your new sensor at a reputable location, and the box isn't beaten up or showing greasy fingerprints, I wouldn't worry.

The absolute worst case scenario is a new sensor coming out of the box dead, which happens sometimes, so you just take it back for another one.

After over 30+ years of working on cars/trucks/tractors, I can count the number of "new in the box" dud parts on the fingers of one hand.

Ok that was my same thinking. But I actually called the dealer and it was the same scenario except they packaged the part in bubble wrap. But I will certainly take your advice and thoroughly inspect it for fingerprints and or scratches. Thanks for your help!