Hey, with my stock injectors in and the walbro 255 installed with key on it would hold about 58psi on the gauge. Running about the same 58 psi. Right before Wheatley tuned my truck with the procharger I installed 44# 8.1 marines in the parking lot. Jumped in the truck and turned key on and pressure would fall all the way to about 5 psi in a matter of seconds. What could possibly be the problem??? Even showing 5 psi on the gauge, turn the truck over, starts no problem and holds 60psi... Wot 64ish. Will not hold pressure anymore with the key on???? Any help welcome!!!

 

Could be a injector stickin open.

 

if those are ebay injectors, i've heard of several people having problems. if you bought them on eBay, then contact the person you bought them from. +1 on the stuck injector.

 

What can I do to remedy that? Lucas fuel injector cleaner?

 

There def. not ebay injectors... How can I find out if thats the problem? clamping the return line?

 

If you have someone that has the good snap on scan tool you can watch each injector on the screen. If one is leaking the others will compensate for that one. (hard to explain but easy to watch on screen) I used one on my wifes Pontiac to fix a hot start problem. We found an injector leaking down. Used GM injector cleaning procedure and have not had a problem since. All this can be done at a dealership.