motor stalls when it warms up and wont start back up ?
Asked by kev323 Dec 28, 2016 at 06:46 AM about the 1988 GMC Sierra C/K 2500
Question type: Maintenance & Repair
I have a 1987 GMC High Serria 2500 4x4 350 TBI . The motor startsup and
idles fine you can even rev it up and its fine but once the motor warms up it
dies and wont start back up for a day or two . I have replaced the fuel
pump,tbi sensor , mapping sensor, ignition module ,new distributor
cap,rotor bug, plugs wires , plugs, temp sensor. at this point i have no clue
what it could be can someone please help me out
6 Answers
also i have spark its alittle weak and no fuel pressure after it dies
A weak spark is not good, have the coil checked out, spark should be white in color if you check, also on those tbi throttle body's, the built in regulator spring gets weak so it cannot supply the 9 to 13 lbs fuel pressure required to run the motor. There is a rebuild kit available for the TBI.
i rebuilt the tbi but it didn't come with a new spring and it only looses fuel pressure after the motor dies and wont start back
Look down the throat of the throttle body after turning the engine off after starting it, the warmer the better, and look to see if you can see any fuel dripping from the injectors onto the butterflies. If there is then it is not holding the fuel pressure.
Still here, so what does the spark look like, white or orange? White would be a good spark. And how do you know it looses fuel pressure when it dies? One more thing to look at before getting back here would be do you notice any dripping of fuel from the injectors when it is running? The fuel spray should be a nice cone spray, a mist, not bigger drops of fuel.
