2000 Tahoe

i'm having real trouble with this vehicle and it's very frustrating. I've tried several remidies including chevy dealerships, which claim they have never run across the problem. There responce is we'll put the scanner on it, for $60 to $80, with no success. Sequence of events below.
1. Replaced air filter, fuel filter, oil and filter, and orginal plugs, whiched caused a miss fire.
2. Had Rudolf Cheverolet, in El Paso, clean throttle body and fuel rails, which they claimed caused the problem, however the miss came back.
3. The 1 and 2 plugs were carbon tracking causing the miss. I replaced the plugs, again, with the suggested plugs, upgraded model.
4. To eliminate the coil, wire assy. I switched 1 and 2 with 3 and 4 coil and wire assy. It worked great for a while however the carbon tracking came back to 1 and 2.
5. i can switch plugs to other cylinder and they will work great, however the carbon tracking and miss will reoccur.
6. When in cold start the engine runs OK, when warm the engine will start missing, especially on excelleration.

Sounds like a problem I am having with my 2000 5.7L Z71 Tahoe, 53000miles.

(I really think my truck is possessed, wait until you read the other problem I had 2months ago at the end of this)

I was driving from Pittsburg back to NC. I am at McD's drive through and the engine just dies, no warning whatsoever. I start it up, runs fine and continue. I drive a few hundred miles more and am pulling into a rest area parking lot at about 10mph, engine dies, again no warning. Stop the truck, put in park, and start it up. Runs fine. Continue to drive it another couple hundred miles and within 30min of home...on the highway...going 80mph...enigne dies...no warning..no power sterrring...so i carfefully coasted to the shoulder and stopped. Tried to start and it has difficulty starting, I figure..maybe slightly flooded from me pushing on the gas when it was dead. I wait 2min and start it up, it runs fine, I make it home and drive it to work the next day. No problems. Not once has a "service engine light" came on. The oil is fine, the engine temp is fine. So I take it the same engine shop that has serviced my truck before. The store owner hooked up this fancy computer and looked at the misfire history..nothing...he looked at all the readings...no a problem. So then we took it fo a 10min drive and monitor the puter....not a single problem. A couple ideas we had were inginiton coil or the plugs. The plugs are 4000 miles old ac delco plantinum. So I left the truck with the mechanic and they drove it somemore over the past 2 days and not a DAMN PROBLEM!!!!

SO here is the other problem I had 2 months ago.... I was getting misfires, service engine soon lights, and rough idling. So I took the truck to a chain mechanic shop(Merchants). They said I needed new plugs, iginition wire, distributor cap, and rotor button, and fuel system clean. 1 week and $600 later the same problems were back. I know, I got taken for a ride on that one. So I brought it back, and they said my injectors were clogged, they cleaned them at no charge. 1 week later problem is back. I then take it to a Chevy dealer and they say I need all injectors replaced and will generously do it for $1200. I say ha and no thanks. I then take it to a engine repair shop. They tell me that #1 and #2 cylinders are misfiring and the tube that goes from the injector is clogged. So they replace 2 injectors, fuel filter, clean the fuel system, and the air intake. 2 days later problem is back. I take it back to engine repair shop...Now injectors 3 and 4 are clogged. So the mechanic takes a gas sample from the tank and the clogged injector and finds SAND. So they replace all injectors, clean the fuel system, and cleaned the gas tank, replaced the fuel filter. I have no idea how the sand got in there, but the mechanic thought I was vandalized. So I got the insurance company involved and they pay for everything, even the $$ i spent at the chain mechanic shop (Merchants). So a few days later the problem comes back. I take it back , they pull the tank and still find sand stuck to the walls of the tank. So then they replace the fuel tank, fuel pump, filter, clean the fuel system again. I get it back and truck runs fine. However I did have to bring it back for a few of their human error screw ups, like bending a contact on the mass air flow sensor (which caused a service engine light), not tighening the clamps on the fuel hoses so gas leaks. SO after all that I havent had problems for a month until my trip from Pittsburg.

Sorry for the novel, but I wanted to share my bad luck. I need a break or just to get rid of this truck. The good news to this sad story is that the insurance company has paid for almost all of the SAND problem. We have no answers for this new problem. I am driving next week up to the Mtns of West Virginia, lets pray I dont have this problem!

I am actually having the exact same stall problem with my 2000 Tahoe Z-71 as I write. Over the holidays I was travelling and it happened twice. Basically the engine would start and I would get moving and the Tahoe would stall. After stopping and getting back in park, the engine would restart no problem and then I was able to drive. This actually occurred twice on successive nights. I happened to have a buddy working at the local Chevy Dealership in the service dept, so I took it in and we looked through everything. No codes from the computer and the only potential electrical problem we could find was a slightly loose ground wire leading from the battery to the block. We tightened this and everything seemed to be fine. The main reason we believed the problem to be electrical was because upon stalling the vehicle, the clock was reset to 1:00. Thus, there had to be a complete loss of power from the electrical source. Well everything was fine and we got back to home and my wife was driving the Tahoe. Tuesday she went to start it and had the exact problem. So I took it into the local dealership here and then had it overnight and all of yesterday. Finally they called back saying they could not get the problem to duplicate and thus couldn't find any problem. I drove the Tahoe today and it happened just the same. My question is: why would there be a reset function to the clock? When this happened to me today, there was two sorts of stalls, one that reset the clock and another "less-invasive" that did not? I'm pretty much at a loss and I think it may be fuel related, but again why the clock resetting? If anybody has any suggestions, please help out.
Thanks

first of all you need a scanner to see which cylinder is actually causing the misfire, once you know that then we can diagnose this properly without throwing a bunch of parts on it. I have seen water cause cylinders 7 and 8 misfires, just a drop in the fuel rail will cause a injector problem, remove the fuel filter and blow out the fuel on cement and see how long the fuel takes to evaporate, whats left will be water, if its not that, I have see injector wires chaff on the ecm connector, the wires make a hard turn just off the connector and can chaff on the connector, the connector is grounded.

corduroy's problem sounds like one I had on my daughter's '96 Tahoe. Ended up being the fuel pump going bad intermittantly until it finally crapped out.

Carbon tracking on the outside of a plug is caused by moisture creating an easier path to ground. Weak fuel pump can cause lean fuel mixture on only one or two cylinders. Heat damaged coil wires create less insulation. Lean condition can cause(but maybe isn't problem here) higher spark gap resistance, leading to arcing.Hope this helps.