GMC Sonoma

I have a 01 GMC Sonoma with the 4.3 engine. Auto trans, 2 wheel drive. I have recently had problems with what appears to be the fuel pressure regulator. When the truck has been sitting for awhile, it cranks for several seconds before starting. When it's warmed up (hasn't sat for long), it lights right off. I also have noticed that my gas mileage is worse than normal and I smell gas on occasion with no sign of leaks. Sounds like the fuel pressure regulator. Now, where is this silly thing? I have looked in the Chilton GMC manual and the Motor Light truck manual. No luck in either. Thanks for any info.
Jim W
September 30, 2007.

Good guess on the problem, the regulator is located under the upper intake and rests on the rear of the poppet connector, the reg is round and has a relief tube and is held in by one clip,

good luck


Oct 18, 2007.
Sounds like you have an injector that is leaking off pressure.

Extended crank is needed to restore pressure.

A pressure regulator won't cause a gas smell or reduce your mileage but a leaking injector will.

If capable. Pull each spark plug to look for signs of fouling.

. If you find one that looks very sooty then pull the injector rail and take that one to a shop to have it cleaned/tested.

. Running cleaners thru the system usually doesn't work

Oct 21, 2007.
Im sorry sir but your wrong

fact 4.3 engine has popet valves, sfi not single injectors that can be pulled out,,,,, they are under the intake

fact a leaking regulator which is located on the rear of the sfi module will cause a fuel smell in the cab ofthis and most other vehicles while running and will cause degraded fuel mileage

Oct 21, 2007.