this sucks, everytime i think i get something taken car of another thing pops up, well i decided to check my fuel pressure today after change the plugs and all of them having white tips(lean). it idles at about 35 psi and if i blip the throttle 2500 maybe, i dunno i was under the hood, it dropped to 30psi on the gauge. Fuel pump toast? the hose isnt long enough to tape it to the windshield, but can i pretty much assume that the problem will not get better under load?

 

When you "blip" the throttle, fuel pressure should actually rise, because the vacuum compensation is being reduced. Sounds like your fuel system is weak.

 

well this is exactly what it did, when i blipped the throttle it jumped to 40 then back to 30 in an instant. someone suggested to check the voltage to the pump, do you know which wire and a pic or something?

 

sounds like you're not checking it the right way. At idle, remove the vacuum line. Should read between 41-47psi. Reconnect the vacuum line, should drop in proportion to intake manifold vacuum.... the 35psi you got at idle is "normal" IF that was with the vacuum line connected.

When you "blip" the throttle, the vacuum disappears, and the pressure rises back toward the "no vacuum" level, so rising to 40psi is "normal". Then as the throttle blades snap close, you get a significant increase in manifold vacuum, and the pressure would drop dwon below the 35psi you had at idle with the vacuum line connected. Obviously, "blipping" the throttle is a sort of useless test.

So far, it doesn't sound too bad. The trick it to run it on the road at max RPM/load and see if the fuel pressure holds within 2psi of the "no vacuum" reading. If your gauge hose is too short to do that test, get the right gauge.

 

ok, i saw the error in my ways, i did the test again, at idle with the line connected its about 30-31 psi when i take the vacuum line off it goes to 39, i got the guage out of the hood so i could read it, it held 39 to redline

 

Then the fuel pump or the filter is "marginal". To meet the minimum spec, should be a couple psi higher. 43.5psi (no vacuum) is the pressure the injectors are flow rated at. Anything less reduces the flow.

 

ok well how much could this be hurting performance? my car is running like crap, its throwing a code but im waiting for my neighbor to get his scanner back so i can scan the car