Is 55psi too much for fuel pressure???

[kreymis]

i finally checked my fuel pressure because i suspected ti to be too low. with the engine running and vac hose conneced it was around 55psi. my setup is 42lb inj strim at 6psi. the reason i thought pressure was low is because it has a tough time restarting after its warmed up. i have to pump gas pedal for engine to fire up. should i drop it down to 45 psi???

 

[Chythar]

Stock fuel pressure with the vacuum line removed from the fuel pressure regulator is 38-40 psi. With the vacuum line hooked up, you should see around 33. Sounds like your fuel pressure regulator is failing.

 

[kreymis]

i do have an adjustable regulator. what should my pressure be at with my setup?

 

[HankyGT]

Generally 39#s vaccum off and vac hose that was removed plugged (use your finger).

Different tuners will ask for different baselines, and and FMU can change things aswell...although you shouldnt need one with a 1:1 rising rate reg.

 

[ProKiller]

hmm, mine is also at like 55 at idle according to my elec gauge hooked up to the schrader valve....

 

[kreymis]

hmmmm. im lost. what could be giving me my hard restart. i cant believe i have to pump the gas pedal on a fuel injected car to get it started

 

[divit250r]

If you're holding it to the floor, that shuts off the injectors during cranking. It's how you start it if it's flooded. Pumping the pedal shouldn't have any real impact on the fuel, should it?

Scott

 

[ProKiller]

the larger injectors at hot start is a common problem with setups like ours that can be fixed with a tune. I have a PMS and there is a field for start fuel.

its not your fuel pressure, its the tune. i was more hmming Cythar's comment

 

[greengoblin95]

the most likely reason why your car has a hard time restarting is because the 42's are just soaking your plugs and when you shut it off, they are still wet and they have to dry off a little bit before you can get a good spark. you are probably going to carbon foul your plugs soon if you dont get it tuned. im having the same problem. and i have my fp at 31 with the line hooked it and its at about 40-41 disconnected. im just hoping my quarter horse comes in soon so i can tune my car so i can play

 

[GTA_V6_Mustang]

the most likely reason why your car has a hard time restarting is because the 42's are just soaking your plugs and when you shut it off, they are still wet and they have to dry off a little bit before you can get a good spark. you are probably going to carbon foul your plugs soon if you dont get it tuned. im having the same problem. and i have my fp at 31 with the line hooked it and its at about 40-41 disconnected. im just hoping my quarter horse comes in soon so i can tune my car so i can play

Yeah I think all of us with untuned setups with larger injectors and just a caled MAF have the same problem. Mines not too bad lately though.

 

[kreymis]

my car was tuned. maybe its the high fuel pressure that is fouling out the plugs? should i drop it to 45????or will that cause it to run too lean.

 

[final5-0]

You say it was tuned

By tuned ... If you mean they used an interface or chip to change
values in the pcm

then

Whatever fuel pressure you were at when the tuning was done .......
It needs to stay the same

If you hose around with the pressure .......
then that can throw off all the work the Tuner did with the pcm

Grady

 

[kreymis]

yea. i guess i shouldnt mess with it. im running a autolite 24 i think. i forgot. is there a better performance plug that may make it run better