My 1996 GMC sonoma 4.3 Vortec has 125000 miles. 95% of the time is starts great, runs great and has alot of power.
Every now and then it spits a few times and runs very rough, the only way to keep it going is to hold it wide open. Once wide open it spits and sputters, but usually has enough power to keep the truck going a few miles an hour. Sometimes, however, the engine stalls abruptly. Sometimes it will stat back up, sometimes not.
This behavior will usually clear up after a few minutes, but sometimes is is dead for a while. It usually starts back up after an hour or two.
I have replaced the following items
All O2 sensors Wires Plugs Distributor cap & rotor Spark Coil Fuel Filter
I have brought it to the shop several times, they dont seem to know what to tell me.
Any ideas? I am so mad that I am about to junk it, but I know it is mechanically sound!
TIA
Dean