My 85 gslse has been acting very strange lately ive tried to diagnose the problem but havent a clue. The car always starts fine and about half the time it runs and drives like it should. However sometimes the engine misfires while driving, it doesnt happen at any specific rpm or gear but intermittently. Also it happens quite frequently that the car will start and run but when the engine gets above 2500rpm the engine just cuts out until it gets below 2500 again then starts to run fine until it is revved again. I havent done anything substantial to the car to cause this to happen the only work done was a new alternator was put in and the pulsation dampener was replaced with a bolt. i know there is a small oil and coolant leak but nothing that would cause such an adverse result.

 

Change the fuel filter maybe?

 

"and the pulsation dampener was replaced with a bolt"

this could be a problem here. See if the Doc will respond.

 

Could it be that you left the vacuum hose off for the fuel pressure regulator when you did this.
Or perhaps one of the injector connections is loose and most of the time you are firing on 1 injector.

 

When i did the banjo bolt conversion i didnt remove the intake or the pressure regulator there was enough room to get to the thing without doing so. I checked the injector connections anyways and there was no problem. The first thing i looked at wa the vacume lines and they are also all in order.

 

Could be bad injector harness, maybe a split, or fray along those lines. Id start with the basics first. Fuel filter, maybe drain the tank and see if the tank is deteriorating.

 

I havent messed with the injectors at all i understand they could be wearing but why would the problem persist as it does it only happens sometimes and the engine always cuts out at 2500rpm it seems more like a computer issue to me. I have no idea how to check that though.

 

it turned out to be the throttle position sensor the wiring was bad. I re-wired it and the problem was solved. Thanks for the replys .