88gt88

Ive checked everything. My car will crank, fire, run up to 1500rpm, then immediately die. I changed the plugs, checked the wires, cleaned the cap and rotor. I am getting spark from the coil and the plugs are firing fine. I took off the air box and it does the same thing so its getting air. Now to the fuel system. The fuel pump primes, the relay is clicking and working perfectly. the fuel pump inertia switch is bypassed. Fuel does come out of the rail after its primed, but not an excessive amount. So I have someone crank the car. As soon as it fires I start spraying carb cleaner into the throttle body. The car will idle and run perfectly as long as I do this. I stop spraying and it stumbles then dies. Does this pretty much guarantee it the fuel pump. I also changed the fuel filter beforehand. Thanks for your help. Also if I prime it like 50 times it will stay running a little longer. I actually thought I fixed it and it was idleing fine so I got of the car and it died. Im assuming the fuel pump is priming but not supplying fuel when the car is running.

5.0stanger

Put a gauge on you fuel to watch your pressure...you can rent them at auto zone.

88gt88

What pressures will I be looking for on the gauge? What pressure primed engine off, and what pressure engine idling. The only way I can check the fuel pressure when Idling though is if I spray the carb cleaner and hold it.

5.0stanger

The pressure should be around 30 at idle with the vacuum on the regulator, with the vacuum off it should be around 40. It could just be a bad regulator. Put the gage on, and watch it while someone bumps the key on, then starts it, if the pressure doesn't hold, could be a bad pump.

You change your fuel filter yet?

88gt88

Yup I changed the fuel filter. I will check the fp later and get back to you guys. I pulled off the vacuum hose off the regulator and no gas was coming out so I assumed it was fine.

AdderMk2

yup... go ahead and change the pump

put something good in though... like a Walbro 255lph

88gt88

I was gonna go with a BBK 190 LPH pump. Is that ok? The car is cammed, has rockers, offroad h pipe, flowmaster cat back, gutted airbox, underdrive pullies, 373's, and thats pretty much it.

AdderMk2

although the BBK pump is a walbro pump.... you can get it is a "walbro" for cheaper.... and get the 255... too big is not a problem... however, further down the road, if you need a bigger pump than the 190, youll have to buy another ump... you could just do it right... now

88gt88

Ok it looks like Im getting the 255LPH pump. Since everything is 20 years old I will be replacing the tank, the sending unit, and the pump at the same time. I only want to do this once. My question is will the new sending unit need to be adjusted or can I just install it and be done with it? With my luck I will just install it and the gas gauge will be wrong.

CantStopTheFox...

Summit sells the Walbro as a "Summit Fuel Pump" Great price too!