Please help..not spark or main relay but seems fuel problem. Only occurs after 60-80 minutes of freeway driving on first slowdown where rpm's drop below 1800 on lifting gas pedal. It will start back up but have to keep rev's high to keep it going (at worst) or will stall at 1st stop light (at best). Also happens after long use on hot days. After letting cool for an hour seems OK till gets hot again. Replaced Fuel filter, main relay and think ICM is OK..again it has spark. I have heard Catalytic converter? Pinched fuel line? Out of guesses. I was stuck trying to get home once and sprayed water on the fuel rail to cool and that worked...but next time did not? Now also intermitantly hesitates on acceleration from stop. Also seems like low end torque low. Any help would be GRATLY appreciated.

 

check egr

 

have heard of fuel return heat soak. where the fuel returning to the tank gets really hot that the fuel actually tries to evaporate from the regulator to the tank so when it goes around again to the fuel rail, its actually not in the liquid form anymore but vapor so u get either pre ignition or post ignition.

 

My guess would be one of the sensors in the distributor. Have you checked to see if any codes are set in memory? I know the check engine light might not be on, but you never know... there could be one set in memory. Just jump the wires and count the flashes. If you got a crankshaft sensor that just stops the signal it will kill the engine. What sux is that your problem seems to be so intermittent that it will be hard to diagnose. I'd recommend checking all of your battery connections make sure they are all clean and check all your grounds. Clean and sand all of them. Other than that i guess you got to hope it just dies and doesn't start one day so you can maybe find out what is the cause.

 

try changing fuel filter. might be ideal to check fuel pressure as well.