chevy in my blood
Newbie
Hey guys, new here, been searching around for a couple hours and haven't found much that helps at this point. running out of ideas, its my dads truck and hes at his wits end.
He recently replaced the fuel pressure regulator on his truck because it would take a few tries to start and it died on him a few times going down the road. discovered it was dripping out of the vac port. he put everything back together with new gaskets and upon starting it up, here are the symptoms:
it idles okay, noticeable random misfires but fairly smooth
loading up, not wanting to rev sometimes, stumbles like its choking outon multiple cylinders
random misfires everywhere.
gas smell from the exhaust,
backfires on pass. side.
started throwing p0300 and p0154 after he drove it once or twice.
fuel pressure at the test valve noticeably weak by sight (don't have a fuel pressure gauge, don't think he'll buy one either)
sounds like the motor is sucking air for all it can, like gasping for air nonstop
hellacious vacuum.
screams like a banshee and runs great at WOT
one plug wire on drivers side was arching out. could hear it but could not see at night.
what we've done:
replaced fuel pressure regulator
new intake and TB gasket
replaced spider gasket 3 times with new gasket each time (first one was pinched, verified with borescope cam)
replaced plenum twice from two other running engines
replaced egr from a running engine
swapped plug wires from my Tahoe (solved arching plug wire but no other change)
new NGK plugs gapped properly.
new fuel pump & filter.
gone through 2 cans of carb spray looking for vacuum leaks both at idle and while revving or holding idle high
tested for vacuum at the dipstick, none.
so far the only change has been that the arching plug wire stopped.
He's swapping the spider tonight with a used one off one of those running engines.
one thing we noticed is that it idles pretty much okay, but when he revs on it it looks like the spider is getting sucked down. we also noticed that the bracket holding it is very loose, where on the other two intakes it is very tight and the spider doesn't move at all. could this be a part of the problem? the last time he swapped the spider gasket, he used red RTV up top suspecting its leaking vacuum when under a load, and it seemed to run fine revving it in the driveway for a couple mins, but then as we noticed the spider getting sucked down, it started running the same again. we're open to any ideas at this point. I have a diablosport OBDII tuner/scanner, but its made for a duramax, so it will read the codes but wont pull live data, nor can it reset the codes. though oddly, it did on my 99 suburban. got it free from a cousin, don't know much about I. any help is welcome, need to get him back on the road so I can start playing with the new (to me) Tahoe!
He recently replaced the fuel pressure regulator on his truck because it would take a few tries to start and it died on him a few times going down the road. discovered it was dripping out of the vac port. he put everything back together with new gaskets and upon starting it up, here are the symptoms:
it idles okay, noticeable random misfires but fairly smooth
loading up, not wanting to rev sometimes, stumbles like its choking outon multiple cylinders
random misfires everywhere.
gas smell from the exhaust,
backfires on pass. side.
started throwing p0300 and p0154 after he drove it once or twice.
fuel pressure at the test valve noticeably weak by sight (don't have a fuel pressure gauge, don't think he'll buy one either)
sounds like the motor is sucking air for all it can, like gasping for air nonstop
hellacious vacuum.
screams like a banshee and runs great at WOT
one plug wire on drivers side was arching out. could hear it but could not see at night.
what we've done:
replaced fuel pressure regulator
new intake and TB gasket
replaced spider gasket 3 times with new gasket each time (first one was pinched, verified with borescope cam)
replaced plenum twice from two other running engines
replaced egr from a running engine
swapped plug wires from my Tahoe (solved arching plug wire but no other change)
new NGK plugs gapped properly.
new fuel pump & filter.
gone through 2 cans of carb spray looking for vacuum leaks both at idle and while revving or holding idle high
tested for vacuum at the dipstick, none.
so far the only change has been that the arching plug wire stopped.
He's swapping the spider tonight with a used one off one of those running engines.
one thing we noticed is that it idles pretty much okay, but when he revs on it it looks like the spider is getting sucked down. we also noticed that the bracket holding it is very loose, where on the other two intakes it is very tight and the spider doesn't move at all. could this be a part of the problem? the last time he swapped the spider gasket, he used red RTV up top suspecting its leaking vacuum when under a load, and it seemed to run fine revving it in the driveway for a couple mins, but then as we noticed the spider getting sucked down, it started running the same again. we're open to any ideas at this point. I have a diablosport OBDII tuner/scanner, but its made for a duramax, so it will read the codes but wont pull live data, nor can it reset the codes. though oddly, it did on my 99 suburban. got it free from a cousin, don't know much about I. any help is welcome, need to get him back on the road so I can start playing with the new (to me) Tahoe!
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