1998 Sierra 4.3L Hard Hot Start

[Derek Scharringa]

I have been having a hard hot start issue for quiet a while now, and I can't seem to get it figured out. Whenever I try to restart it after the engine has reach operating temperature, it cranks for almost 10 seconds and then fires up. It drives normal, although there is a little bit of a rough idle/surge when its running.

I have a new Spider Injector assembly (with a new fuel pressure regulator), new Distributor Cap, new Fuel Filter, new Engine Coolant Temp sensor, and new Intake Air temp Sensor. My fuel pressure is stable and does not drop when I hook a gauge up to the pressure valve, and my fuel pump sounds normal.

Any help would be greatly appreciated, thanks,

 

[StepsideGMC]

That sounds like it might be a plugged EGR valve. My guess is something to do with emissions or vacuum, since your fuel system checks out. I had a bad Idle Air Control valve do that once to me. The truck would cough under load too though. All of your diagnostic guesses so far are good things to check too.