Truck Not Starting When Cold. I'm Clueless?

[SonomaSLS4x4]

Ok I have a 1998 GMC Sonoma SLS 4x4 with a 4.3L Vin X motor. It is CSEFI Injection. I am stumped on why my truck will not start when it is cold. I am almost positive it is a fuel problem because when I pour a little bit of fuel down the throttle body it will fire up and run fine. This only happends after it sits for more than a few hours but if im running around doing stuff it will start up just fine.

 

So I have changed the IAT sensor, the CT sensor, the fuel pressure regulator, and the fuel filter. I have checked fuel pressure and its 56 PSI with the key off and 55 PSI when its running so to me the fuel pump is good. I did a resistance check on the injectors and they are all 13.5 or 13.6 ohm which is in spec.

 

Any help would be appreciated as I am pretty much out of ideas on what this could be. Thanks

[gmtech4]

what you paid throwing parts at it you could have had it diag'd at a dealer ,getting a diag on the internet is even better ,take it to a tech.

[SonomaSLS4x4]

what you paid throwing parts at it you could have had it diag'd at a dealer ,getting a diag on the internet is even better ,take it to a tech.

 

 

Thanks for your input but it doesn't help me. Dealer prices are outrageous so I would rather do things myself thanks.

 

Anyone else have any ideas. Thanks.

[SonomaSLS4x4]

I have solved the problem. It was a weak fuel Pump. I checked the fuel pressure after sitting over night and it was 50 PSI which is out of spec. Funny thing is when I checked it the day before the truck was warmed up and it showed fuel pressure within spec.

 

Anyway I thought I would let everyone know in case anyone else is having a similar problem.