HX_Guy

Say your idle fuel pressure is 38 psi (with hose attached).
What happens to your pressure when you rev the motor to 3000 RPms and hold that RPM? Does the pressure drop? rise? Or stay at 38 PSI?

I ask because my pressure rises on the initial rev but then drops down to 32 PSI and stays there until I let the car idle again. That doesnt seem right.

HX_Guy

Cmon...no one with a turbo has a fuel pressure gauge?

Anyway, I checked my vacuum at idle at ~3000 RPMs
At idle its at around -280mmHg to -300mmHg and at 3000 RPMs its at -550mmHg when holding a steady RPM (not reving)

Does that sound right?





[Modified by HX_Guy, 11:42 AM 12/7/2001]

Doodoo

From what I remember mine rises and holds. From a dead stop it rises to about 70psi and then drops immediately. At idle I am about 33-35, so when I cruise at about 65-70mph it holds at around 40-41psi.

HX_Guy

Ok I talked to my buddy who has a LS Teg.
He said at idle his vacuum is around -500! So I definately have ALOT less vacuum due to my cams probably, which is why its feeding it SO much fuel at idle/low rpms and is probably why it runs so rich/stalls.

liam821

thats about what i have too...

liam

HX_Guy

Damn cams...see what you did Liam!

CivicV10@18000rpm

Do you have an A/F meter? I thought the ECU in closed loop operation would be able to adjust the pulse width of the injectors if the O2 sensors were reading a rich condition. I guess not.

HX_Guy

Yes, my A/F Gauge is off the scale LEAN at idle (its probably fucked), yet tht car is pumping out so much fuel at idle that it makes me choke! It has 10 times the amount of unburned fuel in the exhaust that it should when idling.

Finest

Are you sure it's an overdose of fuel? Does your exhaust shoot black smoke? How's your gas mileage?

Anyways, too much fuel can actually harm your O2 sensors...which explains the faulty A/F readings. Might want to check if the O2 is clogged or fouled.

HX_Guy

Yes Im 10000% sure

For one, you can smell it! Two, I only got 200 miles from my last tank of gas...thast like less then 20 MPG, and third I had it checked on an emissions machine..at idle its putting out 10 times the amount of unburned fuel it should.

degradated

My fuel pressure gauge stays high if I'm revving high. Do you have a FMU? Yours should hold constant pressure too depending on what position the throttle is at.