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73-87 Chevy _ GMC Trucks => Performance => Topic started by: Tazman on March 23, 2016, 03:06:01 pm
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I try to keep up on helping my truck run at its best. Lately though I have noticed it is turning over more before starting when cold. I changed the fuel filter and gave the injectors a spray but no change in the starting. I am wondering if the fuel pressure could be an issue. Any other ideas out there?
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My truck does the same thing. What's the overall condition of the throttle body like? The fuel pressure regulators like to fail along with the big spring sitting on top of it. Does your truck like to stumble on start up? Mine does that and it's aggravating! Haven't you had issues with your fuel pumps in the past? It could be that they can't build up sufficient pressure quick enough. I've been suspecting mine for awhile now. My driver's side has been replaced at some point but I don't use that tank since it leaks when full. My passenger side lines and connections appear original so not sure if that pump has ever been replaced or not. But the truck runs the same regardless of which tank its running on. Just some things to think about.
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most times its a bad fuel pump relay that causes this problem. once you turn it over for a few seconds the oil pressure builds up and turns the pump on.
do you hear the pump turn on when you first put the key to "on"(KOEO)? do you hear it when you apply 12v to the little red wire on the fuel pump relay (should be about 3" long)
(http://forum.73-87chevytrucks.com/smforum/index.php?action=dlattach;topic=32783.0;attach=32342;image)
(Captain Swampy)
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The fuel pump was replaced a year ago and I also rebuilt the TBI before that(with the help from this site, thanks).I make it a point to hear the fuel pump before actually starting the truck.
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soooo is that a yes? if so check your fuel pressure
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The fuel pump was replaced a year ago and I also rebuilt the TBI before that(with the help from this site, thanks).I make it a point to hear the fuel pump before actually starting the truck.
When you rebuilt the tbi, i guess you put in new injectors?
Hopefully i don't confuse the issue but another common problem is the injectors can get leaky after a while and this can cause more than usual cranking at startup.
(i have a TBI car too.)
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No I did not replace the injectors, that is something to think about doing.
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Yes, the injectors can get drippy after shutdown and this causes more cranking when you go to start it up next time.
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GREAT.
Just out of coincidence, and hopefully i don't confuse the issue further by hijacking, i went to start up the TBI cavalier yesterday (i'm in the process of moving) and the pump won't turn on----so it will crank all day, but won't start.
---All fuses good.
--- i can hear the pump relay click on and off everytime i turn the key.
The car has been sitting quite a while, but could a pump just go bad like that? Just sitting?
The car ran just fine the last time until parked.
Any ideas?
Just when i was thinking TBI is more dependable and simpler than a carb and seriously thinking of changing the truck over to TBI................ :-\