What should my fuel presure be?

[4geze63]

When my car starts for the first time after sitting overnight it starts fine, maintains agood idle for about 5 seconds....then wants to die for the next minuite until it gets going, I have to keep giving it gas to keep it from dieing, Would this be something todo with fuel presure?, also I didnt not install the o-ring and spacer on the fuel pump, does it matter?

It just started to have this problem after I installed my -6an feedline. I have an aeromotive FPR, walbro 255

What fuel presure would be ideal for my mods (or would be be what I have it set to now, 39psi with vac hose off.

intake tube
small 16g
2.5' turboback
-6an feed
walbro 255

My afc+datalogger are in the mail,

 

[temfate]

Is your 255 a high or low pressure unit? I'd imagine you might have a slight fuel leak in your new line maybe... I run 40psi, but 38 or so is normal for a stock car. The AFPR will cause it to be hard to start when it hasn't been running lately, but not for a minute... That's gotta be something else. Check for leaks, and when you get the logger check timing and knock at that rough point... It could be something with your fuel trims, or the ICS?

 

[4geze63]

will do thanks, I also have no leaks and its a regular 255

 

[94surpatalon]

Check your Coolant Temp Sensor. If it is not working it will tell the car it is 40 degrees and so it will dump fuel into it. If it is shorted out it will tell the computer it is 325 degrees.

 

[psychlow]

Uhh... you didn't use the o-ring on the pump?

Yes, that's very necessary. Without it, the pressure bleeds out of the pump while the engine is off. It's also likely that you have a fuel leak in the tank after the pump.

 

[4geze63]

My car ran good with no ring or spacer on the stock fuel lines tho. after Installing the -6an lines it started todo this. shoud i get a oring and spacer then anyways, even tho I dont think its the direct cause.

I dont see how it can be leaking after the pump as it has 2 ring clamps on the supplied rubber hose to clamp onto the pump.


allthough what you say makes sense. I will get an oring and spacer asap. it wsnt supplied in my walbro 255 kit so I didnt think I needed it when installing. can any damage be done as it is now to the pump. does the syntom of the car wanting to die for a minuite after starting go inhand with no oring and spacer?

 

[psychlow]

Well, reading into your post a little bit, you seem to have a fuel pressure gauge and everything. When it wants to stall, does the fuel pressure get low?

 

[4geze63]

im not fully sure, my gauge is on my fpr, ill take alook nextime