Why won't my car start on the first try anymore?
04-15-2017, 07:41 AM
#21
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I have similar problem and need help: Yukon Denali 2004 fuel pressure is immediately on 60 psi, after 2 or 3 seconds I hear a click, a relay de-energizes and the pressure drops immidiately to 0. Any idea please? It seems fuel pump is creating pressure just fine. As soon as I re-turn ignition key (not starting), relay comes on, pressure is immediately back to 60 psi, after 2 to 3 sec same thing, drops to 0 immediately.
04-15-2017, 08:07 AM
#22
Launching!
hey whats up i just recently bought a 97 LT1 with 156000 miles and same **** has been happening it wont crank the first try i checked the pressure changed out the pressure regulator but didnt help the psi goes to about 45 and then slowly drops down.. it takes about 5 secs to start up and ideas what it might be??? fuel pump??
I have similar problem and need help: Yukon Denali 2004 fuel pressure is immediately on 60 psi, after 2 or 3 seconds I hear a click, a relay de-energizes and the pressure drops immidiately to 0. Any idea please? It seems fuel pump is creating pressure just fine. As soon as I re-turn ignition key (not starting), relay comes on, pressure is immediately back to 60 psi, after 2 to 3 sec same thing, drops to 0 immediately.
-KP
04-17-2017, 11:08 PM
#24
ok guys, if your vehicle does not start up the first time then its 95% percent of the time a bad fuel pressure regulator. the earlier years and a return style system and the regulator was on the rail. later years with a returnless style system the pump acts as the regulator.
to diagnose have somebody turn the car on and just before the fuel pump kicks off with the key in the run position use a pair of vice grips and pinch the fuel line shut. if the pressure holds at that point then the injectors are good and are not bleeding off. once you release the vice grip and the pressure bleeds off then its the regulator and in some cases the fuel pump. i had this issue with my car with the later returnless style system and turned out to be the fuel pump. replaced with new walbro 255lph with new harness and fixed.
starts up the first time, every time.
also if you get the oem replacement pump kit, they do typically come with a new harness to fix the crappy original design that was causing the pumps to fail prematurely.
hope this helps, happy wrenching
to diagnose have somebody turn the car on and just before the fuel pump kicks off with the key in the run position use a pair of vice grips and pinch the fuel line shut. if the pressure holds at that point then the injectors are good and are not bleeding off. once you release the vice grip and the pressure bleeds off then its the regulator and in some cases the fuel pump. i had this issue with my car with the later returnless style system and turned out to be the fuel pump. replaced with new walbro 255lph with new harness and fixed.
starts up the first time, every time.
also if you get the oem replacement pump kit, they do typically come with a new harness to fix the crappy original design that was causing the pumps to fail prematurely.
hope this helps, happy wrenching
04-18-2017, 12:05 PM
#25
ok guys, if your vehicle does not start up the first time then its 95% percent of the time a bad fuel pressure regulator. the earlier years and a return style system and the regulator was on the rail. later years with a returnless style system the pump acts as the regulator.
to diagnose have somebody turn the car on and just before the fuel pump kicks off with the key in the run position use a pair of vice grips and pinch the fuel line shut. if the pressure holds at that point then the injectors are good and are not bleeding off. once you release the vice grip and the pressure bleeds off then its the regulator and in some cases the fuel pump. i had this issue with my car with the later returnless style system and turned out to be the fuel pump. replaced with new walbro 255lph with new harness and fixed.
starts up the first time, every time.
also if you get the oem replacement pump kit, they do typically come with a new harness to fix the crappy original design that was causing the pumps to fail prematurely.
hope this helps, happy wrenching
to diagnose have somebody turn the car on and just before the fuel pump kicks off with the key in the run position use a pair of vice grips and pinch the fuel line shut. if the pressure holds at that point then the injectors are good and are not bleeding off. once you release the vice grip and the pressure bleeds off then its the regulator and in some cases the fuel pump. i had this issue with my car with the later returnless style system and turned out to be the fuel pump. replaced with new walbro 255lph with new harness and fixed.
starts up the first time, every time.
also if you get the oem replacement pump kit, they do typically come with a new harness to fix the crappy original design that was causing the pumps to fail prematurely.
hope this helps, happy wrenching
I've only heard rumors of very early 98 models having the fpr on the rail, but I've never seen one. It would also mean there would be two pump part numbers for 98 models, but there are not. I believe a preproduction 98 fbody was used for testing for a few vendors which had an fpr on the drivers side rail, but again I've never seen one. I've had quite a few 98's, and I can remember seeing a few x code vin 97 trans ams on ebay a few years back. (Mostly incomplete vehicles, but they were listed as registerable and street legal)
I had a typhoon intake a loong time ago and it said 98's needed special adapters but mine did not.
So I believe the fpr on the rail for 98 models is a myth
