BlackBirdLSOne

iTrader: (2)

Bought this 98 TA that has a serious misfire. Had the fuel pressure tested and it seems that the fuel pump is only putting out about 35PSI. It misfires and won't rev up. It also hesitates when you give it a little throttle.

I have already drained out the bad gas as well as cleaned the tank and the sock on the fuel pump- then put in some fresh gas. (I will have it re-tested when I can borrow the fuel pressure tester) The guy I got it from had a new fuel pump installed before he parked it and let it sit for a long time... so maybe it just needs a fuel pump... the trap door is already there so if that is all it is it would be an easy install.

Has anyone out there had similar symptoms due to low fuel pressure or a faulty fuel pump? Or if you've had a problem with low fuel pressure what were the symptoms?

Any help would be greatly appreciated. Wanna get this thing on the road ASAP.

HCI2000SS

iTrader: (2)

I'm having a very similar issue right now actually lol! I'm assuming it's 35 psi at idle since it won't rev up?

BlackBirdLSOne

iTrader: (2)

Yeah, I'm hoping so- it's not even drivable the way it sits. I don't have a ton of cash to sink into this thing... what problem is your car having ?

HCI2000SS

iTrader: (2)

Gotcha! Well mine was holding 58 psi at idle (like it should) but would drop to around 30 psi at WOT at redline. Also my car would surge around a 1/4 tank and sometimes stall out. Long story short...the previous owner said the he had a Walbro 255 pump in there, and i come to find out it's Walbro 190, which is good only till 450 hp at the flywheel...friggin idiot lol! So anyways, I just bought a entire Racetronix kit which does have a Walbro 255 and it also sits in the bucket without having to modify it (that's why I was getting fuel issues at a 1/4 tank) and has a new regulator, sock, etc...not leaving anything to chance here lol

What pump do you have in there now? What mods do you have?

BlackBirdLSOne

iTrader: (2)

Well my car is bone stock... I would think the fuel pump would just stop working if it was effed up... Why would it be just putting out low pressure?

HCI2000SS

iTrader: (2)

Well not necessarily. Okay first of all did you use a good manual gauge to check the pressure? No leaks? How is the fuel filter? Could be the regulator as well, but hard to say at the moment

Homeless2bNY

iTrader: (2)

change the pump.

SPEC is 55-60psi KOEO(KeyOnEngineOff)

so even if that's not the root issue,
either way it needs to be done.

replace the fuel pump and filter.

then Recheck.

next step is valve train inspection.