Suggestion for HIGH Fuel Pressure???

[hermesbooking]

OK, Needing some help from you guys. I am pretty much lost at this point, here is my issue:

I have a small acceleration glitch while driving, you can feel it when you give it gas kind of feels like it is missing. I can hardly feel it when it is at an idle due to having a fluxuating idle of about 100-200 RPM

While running I have around 40 PSI fuel pressure at the rail, I have a fuel gauge set up at the end of the rail.

When you turn the car off, yesterday I noticed I had almost 50 PSI at the rail.

Noticed the pressure bleeds down faster that it use to a year ago, but I can't find any leaks, injectors rail all dry.

Have installed NEW in the last year:
4 Injectors
Fuel pressure regulator
Fuel filter
vacc line kit from lindsey racing
MSD Coil
Lindsey racing plug wires
rotor
cap
battery
alternator
plugs

Also changed out the computer for a working good one, did not fix the problem


Did notice that the Fuel pump is not the correct one, someone had to make it work by soldering the wires to it!
Also when the car is running the DME Relay gets pretty warm, almost too hot to leave in your hand.

This problem has been from the beginning, so none of these items has fixed it, was wondering if you got any suggestions

[earlr85944]

try the correct fuel pump

[hermesbooking]

That is what I was thinking as well, but have put soo much money into the car so far, I want to bee 100% sure pump

[db cooper]

I had a similar problem, where fuel pressure was up to 40 psi at idle, and had a bad hesitation when accelerating. High pressure caused it to run very rich.

When I put in the lindsey vacuum line kit prior to this problem, I accidentally swapped the vacuum lines on the fpr and the damper. I switched them back and pressure was back down to 29.5 psi at idle. Runs like it should. It's worth a shot before replacing your fuel pump.

Dave

[Zero10]

If swapping the 2 vacuum lines made a difference then one of them is leaking badly or disconnected. They both come from the same place and should have a Y connector very near the fuel rail.

As for the OP, verify that you have vacuum at the FPR, and that it matches manifold vacuum (looping idle makes me think vacuum leak too...). With no vacuum at the FPR those numbers are right. Also, provide the part number from the FPR, lets make sure it is the correct one for your car.

The FPR can flow quite a lot of fuel, unless you have a massively over-sized fuel pump it isn't the problem. Might as well post up what pump it is as well.

[db cooper]

You are absolutely right. I meant to say that I swapped the hose that branches off from both the fpr and the damper, from the vacuum ports on either side of the throttle body. Can't remember off hand, but that hose needs to be on a certain side of the throttle body because one side has a higher vacuum than the other.

[Zero10]

One side of the throttle body has only intermittent vacuum (IIRC only for the instant you take it off-idle) while the other is constant. That would totally explain the issue

[hermesbooking]

I will try the lines when I get the car running again. I bought a NEW Fuel Pump for it, totaly diff from the one that was in the car. But the line from the tank to the pump that almost does a 180 turn was rigged to make the other fuel pump fit. Had to order that little hose from pelican parts, not too many people had that part! So if you got one keep it as a spare! I looked at the vacc lines, The fuel damper/ regulator attaches to the hoes connection on the back side of the butterfly, Looks to be correct from the decal under the hood. I will kppe informed!Thanks

[hermesbooking]

Well wanted to give an update. Removed old fuel pump p/n 9580810-021, don't think that this was the correct one, built way different and input was really small. Well, so far so good. Starts a lot better and seams to be running smoother. Will give an update at the end of the week.