what are possible issues now

1998 CHEVROLET TRUCK
94,372 MILES
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JOESPRIDE
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truck developed codes p0420 and po430, whiich are low catalyst flow banks 1 and 2, i pulled old parts (found cats rodded out by previous owners) i put on all new catalytics and y pipe as well as all 4 02 sensors, truck ran fine for 5 miles then i shut off for about 3 minutes, upon restart i put in gear it shifted hard and truck sputtered and died, attempted to restart and it acted as though it was either flooding or couldnt breath if tried to rev motor it would die idle was very rough then die, pulled battery term allow cpu to reset reconnected and it ran drove it 5 miles home and it had a couple of times where it lost power then picked right back up, before changing the catalytics it drove fine except for the codes generated and if you mashed down to passing gear it would cough and backfire and sputter a bit any ideas ???? where to lookas no new codes have generated and im afraid to drive it and get stuck somewhere
Mar 6, 2012 at 6:21 PM
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ASEMASTER6371
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i would have a fuel pressure teswt done first.
did you have any other codes besides the 420,430??

Roy
Mar 6, 2012 at 6:36 PM
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JOESPRIDE
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just did fuel pressure test, and it holds 55 psi at idle when reving eng it goes down to 51 never goes below 50 psi
Mar 6, 2012 at 10:04 PM
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ASEMASTER6371
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fuel pressure looks good but you need to see it when it fails. if it stays at 55, then good on the fuel side. if not there may be a spark issue.

Roy
Mar 6, 2012 at 11:22 PM
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JOESPRIDE
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ran the truck today about 10 miles and again once shutoff and restarted after a couple minutes same cenario really rough idle sputtering etc... limped it home and hooked up my scanner showed 1 code p0339 Crank sensor, so i replaced that attempted to drive the truck for a test and now its worse sputtering popping etc limped it home again and now im showing a camshaft sensor code is this normal for one sensor to show anothers weakness i feel like im just throwing parts at this thing which is getting very expensive fast
Mar 7, 2012 at 8:36 PM
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ASEMASTER6371
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yes, i agree when you are guessing.
the cam sensor is the distributor. the only issue they had was the bottom gear wearing out. you could tell that by using a scanner and looking at the cam,crank sync.
did you have the fuel pressure tester on the truck when it failed??

Roy
Mar 7, 2012 at 8:59 PM
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JOESPRIDE
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yes fuel pressure holds above 50 psi
Mar 7, 2012 at 9:09 PM
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ASEMASTER6371
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ok, then it is not fuel delivery. i would look at the distributor.

Roy
Mar 7, 2012 at 9:18 PM
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JOESPRIDE
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spoke with the prevvious owner he saaid fuel pump, relay, and filter were all new, (guess thats why it holds good pressure), i just pulled the dist cap and tried pulling up and twisting the rotor it doesnt seem to have any more play than others i have worked within years past, i also used multimeter to check power to nd ground on the cam sensor thats all good. i was told that a bad torque convertor could be causing issues is there any way to test this (the truck while setting still will idle smooth at 700 rpm and rev to hearts desire without missing a beat but when driven it sputters spits and dies
Mar 8, 2012 at 11:00 PM
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