EGR Trouble

07 6.6L Turbo diesel keeps popping EGR 402 codes. GM cleaning procedure done ($90). EGR Valve replaced (free). No codes for a couple weeks then bam... three times in the last week. Reset with code reader each time to see if it was a stray code or a real problem. So what to do next? The dealership should be responsible at this point for tracking down the problem, but apparently they don't know how.
Reply to
MAMM (maybe a mechanical moro
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"MAMM (maybe a mechanical moron)" wrote in message news:XiBml.10639$ snipped-for-privacy@newsfe16.iad...

Has this vehicle been modified from stock? Like a K&N filter or other instake mod? A MAF sensor issue or something stuck to it can throw this code.

Reply to
Augustus

Nope. This truck is stock. No exhaust mods, no programmer, no chip, stock air filter (although at the price a K&N actually looks economical). It does have over 90K miles on it.

Reply to
MAMM (maybe a mechanical moro

Might try changing fuel source. The fact that it is fouling out so soon tend to suggest incomplete combustion due to injection timing or fuel quality. Also is engine "loaded" a lot of mostly loafing.

Reply to
SnoMan

Its says P0402 Generic EGR Excessive Flow. I decided to keep an eye on it and wait for it top pop up again so I would know exactly what I was doing when it came up again. Of course after popping up several times only a couple days apart, it then decided not to pop up again for a couple weeks. In the intervening time I have done around town driving, freeway driving, and moderate weight towing to including a 3000lb boat. It popped back up again this morning finally with the same code cruising down the freeway with the cruise control set at 65mph and the truck loafing along in high gear.

Reply to
I R AN IDIOT

Excessive egr flow is usually caused by a partially plugged exhaust system. On gas engine cars it's usually due to bad catalytic converter. I don't fool with diesels but I would guess there could be something that could get stopped up in the exhaust system.

nobody #1

Reply to
nobody #1

Well, I took it back to the dealer on Monday who said they went through it from stem to stern, and said it was perfect. Today just cruising along at

55MPH it popped up again. I driove straight to the dealer,and their next step is to replace the EGR again.
Reply to
I R AN IDIOT

Trying to fix something like that by throwing parts at it usually doesn't get very good results. You need to tell them it's *diagnose them repair* it seems they don't know that. The problem with a lot of dealerships is they have an unlimited supply of parts and a limited supply of really good techs.

nobody #1

Reply to
nobody #1

Yeah, buddy! I get frustrated by that too. In bigger markets you can go to different dealers until you find a shop that will take care of you, but GM severely limited that by prohibiting cross line warranty service a few years ago, and in smaller markets you often only have one choice now. Personally in my market I like the commercial sales staff at the Chevy Dealer, but like the service shop at the GMC dealer.

Waddayagonnado!

Bob La Londe

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Reply to
Bob La Londe

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