JohnAMcG

Here's where I am at. 57k miles, I bought it with 6 miles on.

CEL lights and code shows p0307. Runs rough. Clear the code and 4 days later it returns. Check the plugs and wires and everything looks good.

Next day light is out, although I still feel like it is missing occasionally. Light comes back next time truck is started and off the the dealership she goes.

They have the truck all day, and despite reiterating to my service manager that I need to be informed of the status today, I get no call and no one is there 15 minutes prior to closing. All my calls, which were many, were directed to VM.

This morning I get a call and I am told they want to flush the crank case, clean the throttle body and change 1 spark plug for 500 dollars. I am told the plug doesn't look bad. (I know this) I have no diagnosis, and am very frustrated and miffed.

I am told to completely disregard the oil life indicator as well as the manual, and to change get my oil every 3000 miles.

Is this what I can expect from GM warranty service? To get charged for PM that may nor may not be related to a problem that has no positive diagnosis and is under warranty?

Manual lists plugs as 95k miles. Although apparently that is just toilet paper.

I am having the oil changed (30% oil life remaining), and I will probably make an issue of the plug, being charged for it, and I do not expect the problem to go away.

It looks like they just want my money. I have a feeling every thing not covered under warranty will be cleaned, repaired, then replaced on my dime prior to any actual solutions being discovered.

Chevrolet Customer Service

Hi John,

I truly apologize as I understand how frustrating this may seem. We want to look into this more and provide additional assistance. Please feel free to send us a private message along with your VIN, current mileage, contact information and preferred dealership. Looking forward to your response!

Patsy G
Chevrolet Customer Care

JohnAMcG

Well, here is where I am now. They tried to charge me for the diagnosis and the plug for something like 175. They tried very hard. I met with the head manager with the old plug in hand and we agreed it was a symptom of a larger problem that will come back, and did not charge me for the diagnosis or plug.

I think I know what is going on. The AFM is allowing oil to pool above the 7th cylinder in V4 mode, then dumps oil into the cylinder when it goes back to 8 cyl. The plug was covered with silvery deposits, concistent with oil and fuel additives.

The part that really infuriates me, besides the hours long fight to not pay almost 200 dollars for a spark plug, is that I am now getting better average fuel consumption than I have gotten EVER. By over 2 MPG!! What was wrong when it was new?

So AFM costs me plugs, a quart of expensive synthetic every few weeks, and any confidence I had in the reliability of the engine, so that I can theoretically save a few pennies on Gas.

I think I may need to research this further and perhaps speak to attorney. I will probably be out of warranty when the problem recurs and I will have a 45k paper weight. Seems there could be many thousands in the same boat.