Just put in my Walbro 255 the other day and since then the car has had many problems. It takes forever to start, stumbles sometimes, idles badly, and is slower than before. None of which were present before the new pump. I haven't checked the pressure cause I spent my last bit of available money on the pump. However, I don't think it holds pressure because 4 hours after starting it there is no fuel pressure when I open the schrader valve. I have changed the fuel filter also.

Any ideas.

 

I would check the pressure. Either is in no sending enough, or you are running way to rich, but then fuel should have been coming out of the schrader valve when ya opened it. Check the pressure and then you can get a better idea.

 

You need a gauge to check it.

Curious, how did you know your old pump was bad without a pressure gauge?

 

I replaced the old pump mainly because I didn't think it could handle 400+rwhp. Also it has been very loud in the past and lately it got quieter than usual and it had 160k miles on it.

But even with that pump the car would start up immediately and run great up until the new pump went in.

 

Maybe the new pump is bad. It can happen.
Or the connection between the pump and the assembly is loose and bleeding the pressure back into the tank.

 

your losing pressure somewhere..my first guess is at the new pump.. possibly your fp regulator... but not likely unless for some reason the high volume took it out..check the vacuum line to it for fuel...... who did the install?

good luck let us know what it was...

 

interesting, i just bought a walbro 255 and it went out in less than a week. Giving a nice steady 20psi, i think the regulator spring is stuck on mine.

 

well here's a problem i ran into stupid me i didnt tightened the hose clamps tight enough, if i were i would check all your connections before considering other problems, trust me on this one, good luck

 

I checked the pressure today and I'm getting about 25 psi at idle and it doesn't increase at all. When I turn the key on its showing about 2 or 3 psi. I'm guessing its just a bad pump?

Thanks

 

How did you connect the main fuel line to the pump? What happend with me was that the fuel line wasn't clamped down hard enough and I was losing fuel pressure.....it eventually left me stranded in the middle of the road. BE SURE TO CLAMP it down TIGHT!


-B

 

I used the supplied rubber hose and hose clamp, I put it on tight, but I guess its possible that it is not tight enough. I'll check it this week when I go in through the trunk. I didn't want to butcher my car but it looks like I'm going be in there alot and I don't have the time or patience to cut my exhaust and drop the rearend every time.

Thanks

 

i could almost bet that the rubber hose came loose! did you tightned the clamps with a screwdriver or a socket? if you did it with the screwdriver it definetly came loose becuse of the vibration and caused the hose to disconnect from the pump i know from past expierence and never will i use a a screwdriver again use the socket i think its a 5/16 or 7mm socket. trust me i might not be a very good mechanic yet but by all the mistakes i done in the past sure getting there, good luck bro and let us know what happens. laterz