Hi guys, im looking for some help. I have a 98 blazer. 4 door 4x4.lately my truck has been missing pretty bad. I recently replaced plugs, wires, cap, rotor and fuel filter. Also I'll tell what else is wrong with the truck so it may be easier to help. My fuel gauge is not working properly.And as soon as the engine is shut off, and after the pump primes when koeo the pressure fuel pressure drops to zero within a minute or two. And ideas to help me out. Thanks.

 

All of the indicators relate to the fuel supply system,and it sounds like you actually answered your own question with the pressure issue,so follow your instincts and do what needs to be done! Search this site and all your questions will be addressed!

 

That's a pretty fast drop. I would suspect the fuel pump, but you can also look down the passenger side of the throttle body. If it looks really clean then you either have a bad fuel pressure regulator or leaking injectors. Or you can check out the diy section to see how to make a gauge to dead head the fuel pump to rule it out.

 

Thanks guys. I had my coil and icm tested today both were bad. So I replaced them. Still misfiring. My car has codes p0300 and p0452. I went to try and test the pressure and determine if something in the front is leaking or my pump is leaking but I never got all the parts to do that today. Might not get to it for acouple days, weathers calling for rain.

 

If fuel pressure drops that fast it's a fuel issue. Since it is missing i would guess its leaking in the intake and not the fuel pump assuming it maintains around 60 while running.