Hi everyone,
It seems to be that time of year when my truck runs like crap again. I have a 1995 GMC K1500 5.0L with TBI. All summer long it starts and runs perfect. Once cold weather comes around (temperatures around freezing and below), I start having cold start issues. I crank once for several seconds, and it will start briefly at a low RPM, and then die. Crank again and it fires over, runs decent for 30 seconds or so. Once I put it in gear and let the clutch out, it will start bogging down and sputtering under any load. The idle is also lower than normal. Occasionally it is so bad that the truck will die and restart several times while moving around 10 MPH, jerking back and forth as I hold the gas to the floor to make it stay running. This can be very exciting pulling out into traffic. If I just let it idle for a while before driving, the idle will get slower and slower until it just stalls out. If I 'help' it stay running by feathering the gas and revving the engine several times it will clear up. During this process I get a cloud of steam/white smoke out of the exhaust. This behavior gradually clears up within the first mile from the cold start and it then runs perfect.
I have replaced the coolant temperature sensor (the one the ECU uses to adjust fuel trim, not the temperature gauge sensor) to no avail. I'm not sure what else to check. Either something is wrong, or the TBI system just doesn't atomize fuel well when cold. It seems to run like a 2 stroke that hasn't had enough choke to warm up yet and keep running on its own.
Anyone else deal with this issue on a TBI?
It seems to be that time of year when my truck runs like crap again. I have a 1995 GMC K1500 5.0L with TBI. All summer long it starts and runs perfect. Once cold weather comes around (temperatures around freezing and below), I start having cold start issues. I crank once for several seconds, and it will start briefly at a low RPM, and then die. Crank again and it fires over, runs decent for 30 seconds or so. Once I put it in gear and let the clutch out, it will start bogging down and sputtering under any load. The idle is also lower than normal. Occasionally it is so bad that the truck will die and restart several times while moving around 10 MPH, jerking back and forth as I hold the gas to the floor to make it stay running. This can be very exciting pulling out into traffic. If I just let it idle for a while before driving, the idle will get slower and slower until it just stalls out. If I 'help' it stay running by feathering the gas and revving the engine several times it will clear up. During this process I get a cloud of steam/white smoke out of the exhaust. This behavior gradually clears up within the first mile from the cold start and it then runs perfect.
I have replaced the coolant temperature sensor (the one the ECU uses to adjust fuel trim, not the temperature gauge sensor) to no avail. I'm not sure what else to check. Either something is wrong, or the TBI system just doesn't atomize fuel well when cold. It seems to run like a 2 stroke that hasn't had enough choke to warm up yet and keep running on its own.
Anyone else deal with this issue on a TBI?