hi guys
my 98 tahoe 6.5 is running very smokey at low rpms under load in low gear. if i tromp on the gas pedal it usually stops smoking. but sometimes it smokes a lot. and the black smoke stinks like burning rubber. the engine itself sounds good, runs cool with lots of oil pressure. the check engine light is on, but the previous owner said it was always on and off. if anyone out there can help thanks a lot in advance. money is tight these days i'd like to try to fix it myself.
thanks everyone
andrew

do you know what code its throwing? just guessing I would say EGR/Boost problem. If the light comes on at idle, and goes away when you give it some throttle, you can bet its the EGR giving fits, conversely, if it comes on at highway speed or you have excessive black smoke/low power, you can bet its a wastegate problem. Both systems operate on the same vacuum system so a leak would cause problems for both. Did you ever figure out your stalling problem? Sounds like the Oil sender switch located either behind and just to the drivers side of the fuel filter on the back of the block or in the Valley. Easy to tell, just open the bleed on top of the filter with the truck idling and see if fuel comes out. If it does then your lift pump/sender switch are working, but if it doesnt, well then you can bet its the oil sender, which would explain why you can start it, the truck will run the supply pump while the starter is engaged, and as soon as you let off the starter the oil sender takes over. so when you start it, it primes the system up it can run normally for some time, especially in the shorter wheelbase models like yours.Edited by: Texas Diesel Guy