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Little bit of problems

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Old Nov 26, 2008 | 05:50 PM
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Default Little bit of problems

Im going to give this in as much detail as I can.

Truck runs fine when I am not in it, drives perfectly. Now at WOT it spins the RPMS but it bogs down. I am thinking it is clogged catalyctic converters (out of first gear it does a little pa pow backfire I am guessing) but it also could be the feul pump.

Need some input from some gear heads.



thanks
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Old Nov 26, 2008 | 05:52 PM
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fuel filter/regulator maybe? I'd be looking at fuel pressure
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Old Nov 26, 2008 | 05:56 PM
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Originally Posted by 00ChevyScott
fuel filter/regulator maybe? I'd be looking at fuel pressure
I did cahnge the feul filter. How do you check the regulator?
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Old Nov 26, 2008 | 09:01 PM
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start it up put your hand over the tail pipe(with a rag) and have someone rev it up and see how much exhaust is coming out
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Old Nov 26, 2008 | 09:37 PM
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Originally Posted by andrew383
start it up put your hand over the tail pipe(with a rag) and have someone rev it up and see how much exhaust is coming out
excellent way to get burned if they are stopped up.

you need a fuel pressure gauge. see what pressure does when it starts popping and bogging down.
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Old Nov 27, 2008 | 07:21 AM
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Originally Posted by Truckshop
excellent way to get burned if they are stopped up.

you need a fuel pressure gauge. see what pressure does when it starts popping and bogging down.
hence the rag .if its done n a cold start it wont be hot.if he was not getting fuel the rpms would not come up like he stated in his first post....
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Old Nov 27, 2008 | 07:43 AM
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Check fuel pressure as mentioned, and check for an exhaust restriction with a vacuum gauge. You'll have to snap the tip off of the port on top of the intake, and you'll need a rubber cover to plug it when you're done. Hook a vacuum gauge to the port and rev the engine up to about 2k with the truck in park or neutral. Quickly let off the gas (snap it shut so to speak) and observe the gauge, it should quickly jump up over 20 mm/hg. If it slowly rises there is a restriction in the exhaust.

Scanning software or a scan tool would definitely be helpful too, so you can observe all of the sensor info and see if something is out of whack. It would be nice to observe fuel trims, O2 sensors, map, maf, knock retard, etc. You could be getting KR that's bogging you down, or incorrect maf readings that isn't allowing the proper fueling...there's alot of possibilities.
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Old Nov 27, 2008 | 11:26 AM
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Originally Posted by budhayes3
Check fuel pressure as mentioned, and check for an exhaust restriction with a vacuum gauge. You'll have to snap the tip off of the port on top of the intake, and you'll need a rubber cover to plug it when you're done. Hook a vacuum gauge to the port and rev the engine up to about 2k with the truck in park or neutral. Quickly let off the gas (snap it shut so to speak) and observe the gauge, it should quickly jump up over 20 mm/hg. If it slowly rises there is a restriction in the exhaust.

Scanning software or a scan tool would definitely be helpful too, so you can observe all of the sensor info and see if something is out of whack. It would be nice to observe fuel trims, O2 sensors, map, maf, knock retard, etc. You could be getting KR that's bogging you down, or incorrect maf readings that isn't allowing the proper fueling...there's alot of possibilities.

MAF could be the problem because I did remove the cone that goes in front. It was taken out right with not throwing any sensors, and it ran fine for a year.
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Old Nov 28, 2008 | 03:30 PM
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Still having problems with it. Going to put a fuel pressure guage on it Wednesday. What should be the proper reading? If it doesn't show the proper reading do I need a new feul pump?
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