fuel pump went out again the other day i decided not to install another junk napa pump in my car.... i am planning on running a 150 shot and upgraded to a 255walbro... after installing the 255walbro i started the car and it runs awefull.... it misses loads up ad blubbers while idling and if u rev it to 2500 and up it kinda clears up but doesnt sound like it did,,,, i dont know if i fowelled the plugs while trying to start it with the bad pump, or if my injectors are goin out since they are originall, or if the 255walbro has to much fuel pressure.... i dont have a adj regulator and im kinda at a lossss..... the car has been a freak ever since ive had it... its always been a strong runner and had more power than i think it should and now its running terrible any advice

 

Measure the fuel pressure at the rail. Check your fuel pressure regulator. That's where I would start. If that checks out OK, then look at the injectors.

 

how much pressure should i have and what ohms should inj read any ideas

 

~43psi primed not running.
injectors should all be about 16 ohms.
If you have a cold start injector, that should be about 4 ohms.

 

you can check your injectors for 2 more things:
1) pull the plugs, if you have a wet cylinder you have a leaky injector
2) with the car running, if you touch each injector you should be able to feel
them pulsing..if not you have a dead injector.

you might want to check your sensors also.

 

i changed my ngk plugs and they were fouled.. i put a new set in and it runs awesome again but doesnt like to idle really crisp reving and sounds great but its not wanting to idle it wants to die when u let it idle back down idk

 

What year is the car? Make sure that fuel pressure is good and that no injectors are shorted out. If that checks out good, check your TPS and IAC valve. TPS should be around .54 volts at idle and over 4.5v at WOT on 89 and earlier TPIs. Something caused your plugs to get fauled in the first place and that something may still be there.

 

its a 90

 

On speed density car the TPS is not adjustable. It should read anywhere between .7 and 1v when the throttle is closed, and over 5 volts when fully open. If you happen to check the TPS, make sure that the signal doesn't fluctuate, but progresses linearly. However, I think your problem is some place else, such as fuel delivery.