02 hard start when hot

[chevyman98]

Put a set of bosch reman injectors(8) in my friends truck. Runs good but when hot now it takes a few seconds longer to start. Filter housing has been rebuilt before and it system holds vacuum. Done checked everything balance rates hot and cold are good. Pulled the new injectors back out had the tested 4 were bad replaced used new seals and return lines. While I was there we shimmed pressure relief valve with 3 m4 washers. Still long crank when hot. Cold using tech 2 commanding full fuel it stays around 22 23k psi. Driving wot rail pressure stays with the desired at about 23k psi and regulator 17-20%
When hot and commanding fpr to 23k psi it stays around 20k psi. Replaced fpr still same out come. I'm leaning towards a pump anything else to try before we put a new cp3 on it

 

[jdlover1]

do you check to see what your cp3 pressure was when starting. It takes 1500psi to crank.

 

[chevyman98]

Yes it builds but slow when it hits 1600-1700 it starts

 

[catman3126]

How do all the engine fuel lines look? find a way to pinch off or cap off the two lines on the drivers side valve cover and pressurize through the bleeder port on the filter housing and see if it holds pressure 10 psi will do. if there is a leak on a rubber line you will see it. I've been meaning to get a couple dorman quick connects the size of the ones on the drivers side head and rig up a test tool to make it easier to pressurize the engine fuel system and look for leaks on the hoses. these trucks are getting old enough now that the rubber is cracking from the heat and age and a small crack will not leak fuel but will suck air.

 

[chevyman98]

The rubber lines are new from ficm to filter housing and from filter housing to pump. Im about to replace the little rubber hose from feed line from metal line to ficm inlet

 

[catman3126]

check the one to the test port also.

 

[chevyman98]

Replaced both still same problem

 

[chevyman98]

Pressured up the system didn't see any leaks. I'm going to say its going to be a pump problem. I pulled the line from fuel filter housing to cp3 blocked off and pulls 13-15in of vacuum when hot or cold. I thought it was kind of low should be around 18inhg correct

 

[chevyman98]

Just for future reference the pump was bad