Fuel Pressure

[Jesse Whitley]

Sorry this is a total NOOB question but im not sure about domestics and the fine tuning of things since I came from the import seen where stuff is a bit different. I know my injectors and fuel pump arent stock, not sure size im sure i could pull one off if needed to check. I live in Albuquerque where its about 6500ft above sea level. What is a good fuel pressure to run. My car seems to run rich but my car wont run if i raise my FP above 30psi. It runs best in the low 20s but im not about to blow my motor up hints the Dumb questions. I know things need to be leaner at this altitude but it just seems to low. Im also runing a caspers chip and any help would be appreciated

87 Buick GN
Mods: Precision TE44 turbo, Larger injectors, FP, FPR, Down pipe with electronic cut out, caspers chip, Built T-350 tranny, upgraded intercooler, K&N intake, upgraded hardpipes, and other suspention and sway bar stuff

 

[Boost231]

something is wrong for sure. you should have a fuel pressure of 42-43 line off. Set it at that and lets figured out whats wrong with the car.

 

[Jesse Whitley]

The car wont start at any pressure over 35psi unless i have my foot on the gas peddle. So 42-43psi is at idle or WOT? But i will raise it or maybe i will get another guage to make sure its correct. I have a knock sensor guage setup on the car and im not reading any knock. No error codes also just to get that out there.

 

[Heg87t]

Fuel pressure is referenced at idle with the vacuum hose pulled off the regulator and plugged.

Check the pressure with another gage. That one doesn't seem right.

 

[Boost231]

set base fuel pressure, then the basics like tps, iac etc

 

[turbojay]

I bet your fuel pressure guage is faulty...happened to me.

 

[Jesse Whitley]

ok i will buy a new one today on lunch and do it tonight at home. Car ran great thats why i was lost when it showed low. Soa good base is 42-43 then?

 

[Jesse Whitley]

OK well i have my pressure set to 43psi. That guage must of been shot. I had error 15 so i ordered a new VDO temperature sending unit and i will hook up my scan master i just got in the mail today. Then pull some runs this week, I will post the rreadings and maybe everyone can give me some Tips on whats going on with it.

 

[87GN_70GS]

Since you don't know the configuration of your fuel system, it would be helpful to obtain a fuel pressure gauge that you can monitor while at WOT to determine if your pump is keeping up or the pressure is falling off.

 

[Jesse Whitley]

Good point didnt think about that. I will look into some options and install one. I was also looking into getting a wideband also.