We got a 2002 Suburban 1500 from our local Chevrolet dealership on December 18. It ran fine upon test drive, etc. The Service Engine Soon light came on on the 22nd, but noticed nothing else irregular. When I started it up in the morning of the 23rd, I noticed a rough idle. Every few seconds the vehicle would shudder, and the RPMs would dip. This continues until the car has driven a few miles and warms up.
On the 23rd, I took it to the dealership to see if they could take a peek since we'd only had it a few days. They did, said the computer threw a code (didn't tell me which one) and they replaced the Mass Air Flow Sensor and brought it back to me. The SES light was off and of course no rough idle because the car was warm so I thought it was fixed.
Today, the 24th, get in it and again, rough idle is back. Same symptoms as before, except the SES light is off. So I thought for a minute, turned off the car, turned it back on and no SES light comes on at all to confirm it's even working. Those guys must have disconnected the darn thing, is all I can think.
Any ideas?
So now, I'm mad, I have a dealership who apparently has no interest in fixing it right.

 

Welcome to the forum...
So the Service Engine light no long illuminates when you turn the key to start but don't crank it over?
When you turn to key to start, but don't turn it all the way to crank the engine, all the available instrument panel lights should illuminate, its how you can check the bulbs basically...
Attached is what you should see for a few seconds, this is for an 07 and up but you should seen something similar, and one of them should be the service engine light...

 

Right, the ABS (I think) comes on, as well as the seatbelt light, but not the SES light.

It was on yesterday ... making me think the dealership just disconnected it. :/

 

Please do post the name of the dealership so that others may chime in when they read this if they have had problems...
I would suggest taking it to another dealership or even a local auto parts store to see if they will check for any codes for you... many code readers will tell you if the "MIL" light is on. (MIL=malfunction indicator lamp) even if the lamp is out...


The reader will read something like this if the service engine light is really out becasue there is no problems, if it shows on, and the light is not on the dash, then the lamp is out.

MIL STATUS($00) OFF
MIL STATUS($02) OFF
ABSLT TPS($00) 17.6
ENG SPEED($00) 592
BARO PRS($00) 98
CALC LOAD($00) 19.2
MAF FLOW($00) 5.69

 

Are you absolutely sure that the little yellow engine symbol doesnt come on at all when you turn the key to the on position. Just seems odd that a chevy dealer would turn off or remove the bulb from the dash let alone go through that hassle. Plus it would be illegal on their part. Now im not calling you a liar nor taking sides with the dealer. And it might've just been a code for the mass air flow sensor. Which was replaced and there would be no more code. So the rough idle could be something else. Clogged injector, bad plug, bad gas, etc. Such things may not give codes. I would go back to the dealer after tomorrow and tell them again about your issue. They should make it right being that 1. You purchased it from them and 2.you have only had it a week or so.

 

I agree they need to make it right and I will be calling them back on Thursday.

The service engine light thing is what I really think is odd. Earlier today I swear it wasn't coming on right before turning over the engine, then this evening when my husband went to check it, it's working right now. I'm confused. :/

Anyway, we are thinking possibly it needs a new intake manifold gasket or whatever it's called. Thoughts?

 

Oh, and the dealership is Ratliff Chevrolet in Llano, TX. Small town.

More info - it blows white smoke out of the exhaust.
The rough idle only happens when the vehicle is cold and in park. Doesn't do it if it's in gear.
This morning, the SES light again doesn't come on when you turn the key to on. Something wrong with the computer maybe?

 

so many texans on the forum. man i envy you guys. i wanna move out there so bad but all my roots are here!

 

Ever hear the saying "I wasn't born in Texas, but I got here as fast as I could!"? Yeah.

Hubs is calling the dealership this morning. I'll let you all know what they say/do. He is thinking that maybe they just clean the MAF sensor and didn't replace it, which is what I *THOUGHT* they said they did. I'm thinking maybe the intake manifold gasket.

 

Well, good news, he said that the dealership said they will come to the house and pick it up from me this morning so they can more accurately see what it does on a cold start and that they will take care of the repairs. So hopefully that remains to be true throughout.

I will continue to update this thread so hopefully it can help others in the future.