Aeromotive fuel pressure regulator failure (Maybe)

[supraguy31]

Ok all, Here is my Delima.....

At Idle my Aeromotive is reading 35 psi on the Gauge and my A/F ratios are great.

Once I give it some gas and hold it anywhere from 1600rpms and above, the Reading on the Aeromotive goes up in fuel Pressure and without letting off the gas (Steady 2000 rpms) it just drops back to stock pressure. Once it does this my A/F pressure goes lean and no Adjustment on VPC or SAFC will fix it.

Does this sound like a Bad FPR....

Any help would be greatly Apprecated.
Robert

 

[mkIIIman089]

Hook up a vacuum gauge, if FP drops as vacuum increases once you have leveled at X RPM, then its working properly.

AFAIK there has never been a failure of one of those FPR, they are damn near bulletproof.

 

[teedoff00]

Yeah I agree the AFPR is pretty stout, I had problems with my liquid filled gauge, it would always seem to jump around so much I could never tell where the hell my FP was at. So if you have have a liquid filled get a good mechanical with the same thread size like an auto meter and it might save you some hours of tuning.

 

[IwantMKIII]

i would guess a vacuum leak

 

[HENRY SIEMON]

which fuel pump you are using????? check the voltage of your alternator..

 

[mkIIIman089]

No vac leak.

MKIV pump.

 

[QWIKSTRIKE]

Check to see if the pump is running 12volts all the time. If not run it full 12 volts directly, or do the 12 volt mod. If not the fuel pump is shot if the vacuum is fine.

 

[supraguy31]

This is a MKII So Im running 12volts all the time.

I think I found the Problem and I have no Idea what the heck is making it do that. At one time I was running vpc 550cc Chip (SUP009B) on 440cc Injectors (BIG NO NO) Rought Idle, and Sputtering and total leaning out so I boutght a VPC 440cc Chip and it fixed all that Problem, Well, I installed some RC 550cc Injectors and Put in my 550 chip since they were a even match and what do you know, Im back to Rough Idle and Sputter at any gas at all and total Lean on my Wideband. This is the Second VPC 550 rom chip that I have put in this car and it hasnt ran correct yet.... Do you have to reset the VPC in any way to get a Different chip to work or is it Pretty much plug and play. I went ahead and pulled the 550 chip out and Put the 440 chip back in and it runs great, Just have to pull alot of fuel out to get the A/F mixtures correct which I dont like doing.....

Anyone can help, I would be greatly Appreciated.

Robert