Hope someone can help. I checked the max pressure coming out of the filter and max was almost 90psi and it leaked down to just under 70 psi. Service port test 62psi but as soon as the pump kicks of it instantly drops to 40 psi and holds. The pressure regulator was leaking gas when the pump was activated so I replaced it. Fixed the leaking gas but I still have the pressure drop. I do have a spider assy. from another blazer that I put on and I still get the pressure drop with it. The assy. from the other blazer should be good. It was running when the spider assy. was taken out.

 

The fuel pump max output pressure & leakdown are within specs, the pump is fine. The leakdown to 40psi is in the plenum. Could be an injector, a poppet valve, the regulator, or something to do with the fuel metering block, (housing for the injectors). Is the injector assembly the original style, (black plastic "wing" clips to hold nozzles in place)?

 

Yes. Both are the originals.

 

Seems the leak is around the regulator. If I put a little pressure on it the leaking stops. I pulled the regulator back out and made sure the seal and the body are clean. Put it back in and it still leaks. It did slow the leak down but still leaks down to around 40psi in just a few seconds. Any ideas oh how to stop the leak here minus buying a new assembly?

 

Could be a bad regulator O ring or the clip isn't holding the regulator in tight enough, or something else ??? Fuel leaks in the plenum allow fuel into the oil, which will cause serious damage to the engine. The old style injector assemblies are prone to a list of problems, better to upgrade it and not have to worry about it.


If cost is a factor, maybe check with a boneyard for a used one. 2003 through 2005 Blazer, Jimmy, Bravada, S10 pick up, and 2002 through 2005 Astro/Safari vans have the new style injector assembly. Just a thought for an alternative