HELP! Constant rough idle.. 2003 6.0L

The trucks got 113k on it, i've replaced the plugs (AC irid plugs), Wires (crane 25ohm firewire), knock sensors, intake gasket, and cleaned the throttle body.. I cleaned MAF with QC electric cleaner also..

The idle stays perfectly still as far as rpms go but you feel it missing the entire time.. like someone is lightly shaking the truck the entire time its at idle. WHAT GIVES! its driving me insane and i don't have a scanner, no one around me has a scanner for these year trucks..

Do the plugs suck? Do i have bad coil(S)... Someone said something about EGR.. ANYTHING SOMETHING!!! lol.. it makes the truck seem like such a peice of $hit when anyone is in it.

Also the throttle is so touchy that hitting bumps the throttle spikes easily and its a mess.. Throttle seems way to touchy, then if you do floor it the thing sounds like its bogged down.. If you hit the gas 50% or so it pulls ten times harder than full throttle.

Thanks! I'm hoping to hear some options for tomorrow so while i've got the day off i can start looking over it.

See if you can borrow someone's MAF and try it. I bet yours is bad.

you think its the MAF, what if i disconnect the MAF does these computers fail over to speed desity and that would let me see if it idles smooth

fuel filter... just a guess... but if you go WOT, and it bogs down, could be the full filter being clogged... to if it's idling rough, might not be getting enough fuel..

Have you done a compression check or leak down test. That wont really explain the bogging, but it can the rough idle.

Quote:

---

Originally Posted by turbochevy

you think its the MAF, what if i disconnect the MAF does these computers fail over to speed desity and that would let me see if it idles smooth

---

I've never tried it on one, but it might run differently enough to tell if that is the problem or not. It wouldn't hurt to try it. It will set two codes, MAF and IAT.

Ya i should do a compression check,.. but i really don't want to know :(.. Not ready to screw with the internals etc.. still dumping money in other projects and trying to pay off the truck.

Fuel filter is a really good one.. I'll look and see if i can find somewhere open thanksgiving to pick one up and throw it on.

Is everyones throttle deadly sensitive or is that somehow related to the rough idle etc..

I've got a ported throttle body from green6.0 that i'm waiting to put on until i think i've got this idle thing worked out...

Thanks again everyone

How often do you guys change your fuel filters and how long can you go before you notice its messed up? And does walmart sell them lol.. looking like wally world is going to be the only turkey day option for a filter.

if you need a stock MAF I have one.

I might need one, how many miles are on yours? My trucks got 113k on it so i'd like to find one low miles or something. what are you thinking for a price.. shoot me a PM if you want. Going to go steal the MAF off another 6L i've got sitting in the shop thats a 03 with 40k on it and see if its helps..i'll let you know.

57 k when i took it off. granatelle came attached to the kn intake I bought and then nelson tuned it so ....

maybe your IAC valve on your TB ?

we will see I might have more, after the wife wrecked it tonight.