First, I wanted to say I love the site and the advice given. Great information that has saved me more than once.

Need some advice on what I should tell the stealer...

Last night on the way home, sitting at a stop light, idiling, the truck began to stumble, like it was missing, looked in the passenger mirror and there was white/light blue smoke coming out of the tail pipe. When the light turned green, stepped on the gas and it took off fine. Got on the highway a minute later, slowly eased into the throttle, no power loss, no smoke, ran great. Didn't do it once the rest of the way home (City and Highway Driving)

The truck did this once before in late January no smoke though. It was going in for the intermediate steering shaft replacement so I mentioned it to the service guy. They checked my fuel filter, about 10,000 miles on the truck at the time, and said I needed a new one. By the time I found out, they had already put a new one on, OUCH that was $150 bucks I could have saved and done the change myself. The service man said that the fuel filter replacement should fix the problem. I asked him about the injector problems some people have had or if it needed to have the computer re-flashed, he said no, the new filter should fix the problem. I made sure I got the old filter and took it home.

Both times the motor stumbled, I noticed the water temp was about 170 to 180 degrees F.

I am wondering if I need to take the truck in and insist they have the re-flash done or if there is another problem, possibly injectors?

Thanks guys, I appreciate it.

Welcome to the "Place"!!! Can't help you with the re-flash issue, I was turned away by the service manager, got to get my ducks in a row.

As far as the fuel filter goes, I once got the dealer to knock 1/2 the price off when they preformed an unauthorized but nessecary repair. Good luck, someone else will address your other issue soon.

O my

My truck has done this exact same problem even after a fresh filter. In my case though, it was about a week after removing the cat. So I was attributing the problem to an EGR related issue and have a block off plate/finger stick on the way.

Techie stuff ain't my thing, but I do a sh_tload of reading on this site so 2nd string quarterbacking is my specialty. :D

IIRC white smoke is usually an indication of injector(s) issues. Black smoke-good, white smoke-bad! That stumble may have been due to a bad injector. Cnce they replace the injector(s) they likely will reflash the truck anyway to reset the balance rates. Listen to me sounding like I know WTF I'm talking about. :o: What the he?? Have you checked the truck for any codes? The SES light doesn't have to be on to throw codes. :confused:

You might post on the "Ask the Tech" forum where the techie types cruise.

MoBoost, I haven't seen other kitty-less members posting problems like yours. Have you checked for codes as well? :) JJ

mine did this exact problem. would only do it every now and then. i had a reflash about two weeks ago and no problems since. but i have gone that long without it happening.. they spent almost 2 hours looking at everything on my engine to make sure it was running ok. they told me that the reflash may or may not fix it. but so far so good....

im going to need to do a fuel filter replacment soon as i am at 15K...

So for those who have had the re-flash...If I leave my edge on, will the edge cause any problems while they do the re-flash?

Lifted, overwhelming concensus is you should remove the E/J before going in for service, regardless of what the service advisors tell ya. Easy enough to remove and reinstall afterwards. :confused:

I had the low idle surge before my truck was reflashed, but I never had a rough idle and white smoke. I have read where others had the white smoke though. IIRC it is usually an injector issue. Where are those techie types? :cool: GM has two TSB's ( Technical Service Bulletins ) for the LLY for Fuel Knock, Surging, & White Smoke @ idle.


Greenscow, if that is your original filter you might do that change much sooner than later. It is amazing how much crap gets in the filters, especially the initial one. Be sure and get the new 2 stage filter with the black stripe around it. Be careful if you buy it at the dealer, some of them are still trying to offload the old filters. :eek:

Later. JJ :)

My truck does the exact same thing. But is there a difference in white or blue smoke? If so what do I do to fix the problem? Truck has 8000 miles and a fresh filter.

ok here is another thing to try. get soime stanadyne, pour it in the fuel tank. then replace the fuel filter. your problem should go away. if it continues and is constant, take it into the dealer. also try to read any codes on it.
it sounds like you have some bad fuel and that the filter is waxing over and causing it to stumble. try running a fuel additive in every fill up, one that does NOT contain alcohol. Stanadyne and Racor are the only ones recommended by GM. hence the reason I suggested it. when mine did it, that is what fixed the stumble and smoke. there are new calibrations out there and the reflash may help with some EGR issues and some smoke issues at idle as well as some surging issues.

Thanks for the advice, Here are the answers to some of your comments.

Right now, I don't have a way to check codes, so I don't know if I am throwing any or not. I want to order a predator in the near future, but I want to get this problem taken care of before I start doing some mods. A Predator, some exhaust, an air intake kit, and some gauges are in my future.

I'll give the stanadyne a try just as soon as I can get some here. I live in Michigan, a couple hours north of Detroit, and haven't been able to find Stanadyne at any of our local stores. Even stopped at a couple of truck stops and no luck. :help2: If it was a fuel delivery problem, would it do it all of the time? Right now the only time it stumbles is when the water temp is right around 180. As long as the motor is warmer or colder than that, it runs fine.
I also checked and the dealer installed filter is the old style LB7 filter. I called the service manager on it and he gave me the line "That is what GM specifies for us to use." If I am going to pay the money for a filter, it better be the latest and greatest, that is for sure. I may have to put a call into GM customer service about this one. :mad:

Thanks again for the help.

I dont have any idle problems or white smoke..but I guess the re-flash wouldn't hurt.

Liftedhdrado,

Do not take any chances by leaving your edge on the truck! If they note it in the vehicle service history that you are using this mod, they may use it against you when deciding to approve or decline warranty work. TAKE IT AND ALL TRACES OF IT OFF!

Do I need to disconnect the EGT Cable that is tapped in the exhaust manifold?

no need in disconnecting the EGT cable. Juat take out your Attitude Monitor. If you have the analog guages, you might be able to leave those in as they aren't linked to any specific module. The Juice Attitude monitor works only with the Edge Juice hence they will know it was juiced.

but wont they see the edge juice in the egine compartment?

Mine was doing the ruff idle thing and white smoke at operating temp stopped at redlight in gear with foot on the brake, if i put it in neutral it would quit. took it in they replaced an injector it ran fine for 2000 miles then started again took it back, this time they did the re-flash so far so good.. now time will tell

I had the same problem, stumble, white smoke. Dealer had the truck for one week. Replaced the injector on #2 cylinder. No problems yet...............