Ok, heres my problem guys. I installed a Walbro 255 a while ago, and cant remember if I have had problems. When I first turn the key on fuel pressure only goes to about 15 or so, basically I have to prime the pump about 3 times to get it between 40 and 50 psi. When the car is running Im pretty sure its in normal range, but I believe my pump is still bad, or the injectors. Is this normal? I am pretty sure you should only have to turn the key once. Fuel injector O-rings have been replaced also. My bigger problem... Low idle. Not when you start the car, but when you let off the gas it drops under 1000, and when I come to a light and stop it sits real real low, and stalls a lot. My friend hooked up a smoke machine, no vacuum leaks, brake booster is fine. This low idle is pissing me off. I did mess with the throttle blade screw a long time ago, and my parts guy told me I need to re calibrate it with the IAC. Im wondering if I should just replace the two.

 

Normal? no.

Check with a fuel pressure gauge to see if the fuel system holds pressure when the car is off. If you have a leaking injector or pump, the 2ish second prime pulse mught not be enough to fill the line up again and re-pressureize it (like when you run it completely dry, you need to prime it a few times).

Also diagnose the pressure regulator, including the vacuum line going to the back of it's diaphragm.

And yes, adjusting the set screw will alter the idle capabilities I believe.

 

10-04 to previous post you have a fueling problem. I have decent pressure days after the ign is turned off, cracks instantly to 42 lb after the 2 second ign on prime shot. As far as idle the PCM tune decides what your RPM at idle is and it varies by coolant temp. The PCM commands the IAC valve to open or close to hold the correct RPM. Plus the TB stop should be cranked open a little this lets in a little air to assist the PCM, but never enough to cause excessive high RPMs. If idle is low when fuel pressure is present I would check, IAC solenoid could be bad, IAC valve seat in TB could be dirty, or your tune is not correct.