Ok i need some mechanical help!!

[liftedcj7on44s 10+ year member]

on those newer vortecs they tend to also get bad crank triggers from my experience. and usually when they do they either throw a random misfire code or no code at all

 

[JeepSound 10+ year member]

I'll be a mechanics apprentice next year, am I aloud to throw out ideas? //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

Anyways, seems like you're looking in the right area, not sure what the exhaust setup is on it though, is he still running the Cat?

Had a buddy of mine with a 4.2 I6 that had the same problem, topped out around 90kmh and could get it past 3k RPM. I told him to check his Cat first, but he went and changed all the plugs, filters, and wires, still no luck.

Changed the clogged and rotten Cat and everything was back to normal.

Again, probably not the solution, but I thought I'd throw it out there.

 

[jeeper07 5,000+ posts]

o2's just gonna cause it to run rich more than likely. A faulty MAF meter wont let the truck run over a certain RPM!If you have any carb cleaner(which isnt suggested but i use it) take and clean the resistor off real good and try it, should take no lnger than 10 minutes to do.

that is correct i ran with out an o2 sensor for a couple months so i dont see that doing this

 

[liftedcj7on44s 10+ year member]

good idea on the cat as well. possibility. run the truck and have someone goose the throttle a few times while you go back to the tailpipe and feel if the exhaust flow is normal! If it feels restricted pull one of the o2's out and see if it helps.

 

[MEMPHISFLEX 10+ year member]

good idea on the cat as well. possibility. run the truck and have someone goose the throttle a few times while you go back to the tailpipe and feel if the exhaust flow is normal! If it feels restricted pull one of the o2's out and see if it helps.

Ok thanks for that tip, im thinking cats but there $800 each threw GM, and i just pulled two plugs and they look good really good, I pulled the MAF and the airintake off to check the TB and the TB and MAF both look good clean, not dirty at all, the airfilter is also good, so nothing to do with that i think it is cats, i said that from day one, but there a pain in the ***, and expensive but ill check the exhaust flow!!

 

[jeeper07 5,000+ posts]

just cut the out and dont replace them if they are that much.

 

[kovemaster559 5,000+ posts]

o2's just gonna cause it to run rich more than likely. A faulty MAF meter wont let the truck run over a certain RPM!If you have any carb cleaner(which isnt suggested but i use it) take and clean the resistor off real good and try it, should take no lnger than 10 minutes to do.

x2

 

[kovemaster559 5,000+ posts]

Ok thanks for that tip, im thinking cats but there $800 each threw GM, and i just pulled two plugs and they look good really good, I pulled the MAF and the airintake off to check the TB and the TB and MAF both look good clean, not dirty at all, the airfilter is also good, so nothing to do with that i think it is cats, i said that from day one, but there a pain in the ***, and expensive but ill check the exhaust flow!!

rip them off i did but now i need to put them on since their is such things as smag laws

 

[liftedcj7on44s 10+ year member]

i think on those chevys you have to buy the whole y-pipe. just get some aftermarket cats and weld them in!

 

[MEMPHISFLEX 10+ year member]

Ok so i put the plugs back in and the air intake system all back together and checked the exhaust flow, and it has excellent exhaust flow, so I took it out quick like to see how she runs, that thing never missed a beat, ran as hard as any 6 liter is going to run, and the ****** only has around 1000 miles on it since rebuild, and it shifts hard, da mn near a 2nd gear scratch out her, so i dont know why its running so good right now, but she runs like a million bucks now, so we will see if it acts up anymore, this week, but right now its running very well, that thing runs harder than my 2000 2500 with a 6.0L did and that had 170,000 miles on it, so i dont now what i did but it runs good now, so we will see if it keeps running good!!

 

[liftedcj7on44s 10+ year member]

well i would still clean the MAF. even though it looks clean it may not be but glad its running good now.

 

[MEMPHISFLEX 10+ year member]

well i would still clean the MAF. even though it looks clean it may not be but glad its running good now.

I sprayed it down with carb cleaner, and my dad did the same thing about two weeks to it also i guess, but knock on wood its running good now, the truck looks and runs and drives like a truck with half the miles on it, good old truck, so just see if it happens, and yeah you have to buy the whole y-pipe assembly to replace the cats, but for now it runs good, and maybe the muffler is getting plugged up on it also, common thing on those and the fords, those big *** mufflers getting plugged up, i hit a bump with it one time and i heard a clung and then the exhaust note changed a bit, so maybe something is loose in the muffler restricting it!

 

[liftedcj7on44s 10+ year member]

possibility. good luck with it though.

 

[MEMPHISFLEX 10+ year member]

possibility. good luck with it though.

Thanks and thanks for the help!

 

[liftedcj7on44s 10+ year member]

No Problemo.