1995 blazer no start,runs if you make it run

[paulleeber]

Originally Posted by paulleeber

Ok here is something I found that may help out anyone with the same problem....

I checked the pressure directly at the fuel filter outlet and sure enough the pressure was dropping off as soon as the pump shut off. According to what I've been told pressure should remain even after pump goes off.

Just had replaced the pump last year but what was bad at that time wasn't really the pump it was the little pulse dampner right in front of the pump. the rubber that slides over the fuel line tube was crumbling (I later found this problem listed in service bulletin from chev) Since I was there I replaced the pump as well. The pulse dampener I got along with the pump at Autozone. Every thing was fine for about a year.

then I had the problems mentioned above with the hard starting. When I took out the gas tank and looked at everything it looked fine. So before changing anything I thought I would do a little testing. I bled my aircompressor down to 60psi (same as fuel fressure should and forced air into the fuel outlet on the pump it self. the pump held pressure fine.
Then I reassembled the pump and pulse dampner onto the assy that goes into the tank and put air into the fuel outlet. This is where I found what was causing the fuel pressure to leak down. One end of the pulse dampener was not sealing around the tubing properly.

So today I went to the chevy dealer and bought one fron them. The material looked different than the after market unit. I talked to several people about this and most times the complete unit is swaped durring a fuel pump including the sender unit as one assy. If this is the case then the pulse dampner gets changed too.

I think what we see when people complain about constantly haveing to change feul pumps in these vehicles is really a problem with the pulse dampner. I will know for sure tonight and will report back

I changed the pulsator and everything is perfect now !!!! thanks for everyones feed back