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View Full Version : need some troubleshooting help...



SinCity R/T
02-01-2009, 07:19 AM
Almost every time I race at the track with nitrous, one or more of my exhaust gaskets (header or collector) springs a leak. Sometimes when this happens the truck runs a little rough, I'm assuming the O2 sensor gets a little pissed off - once the gasket(s) are replaced the truck runs fine, and the gaskets hold up fine with street driving. I have a pretty good idea what's causing the gaskets to fail, and I'm working on a permanent fix.

At the track the truck ran great - set new bests for 60' and ET. I got about 90% of the way home when the truck started running a little rough. I figured it was a gasket letting go like usual, so I didn't fire it up until this morning which was the first opening at the exhaust shop I visit to replace the gaskets. Unfortunately it appears that it is not the gasket that went out this time, but possibly something else in the valvetrain.

The truck will fire up, but idles a little rough. The truck is driveable, but if I try to take it above 2000rpm it stumbles hard. I'm not emitting any smoke, there's no coolant loss, and there's no oil in the coolant. I checked my plugs and they seem fine - they're dry, undamaged, show a little bit of a rich condition (typical). I can hear a bit of ticking from the passenger valve cover - I took it off, but nothing seems blatantly out of whack.

At this point I'm going off the assumption that it's either a lifter, pushrod, or valve... I figured I'd check with other people before digging in any further, because I don't have any direct experience with any of those three components. I'm sure I could use a FSM to pull the rockers/pushrods/lifters, but I've never set lash or installed a lifter or any of that fun stuff for trying to put it all back together - just plenty of intake manifolds, headers, and other bolt-ons.

There aren't any local Mopar shops available (just dealerships), and I really don't want to spend big bucks to have some generic performance shop try to dig into my motor. If it comes to major work I'd rather help offset the expenses for someone from the online community come and show me how to do it first hand so I can deal with it myself in the future. I will most likely use this opportunity to find & fix the oil leak from the front of my engine (have been assuming it's the crank seal), might even install a bigger cam.

Adobedude
02-01-2009, 02:06 PM
Start with pulling the covers to see if a rocker came loose. I had it happen once, I knew something was wrong big time.

DrewzR/T
02-01-2009, 03:25 PM
Yeah I'd pull the covers for sure. I bent a pushrod on the old truck and had similiar symptoms. Installing rockers , lifters, and pushrods is a fairly easy job. Good Luck man.

Duner
02-01-2009, 03:31 PM
I think I would do a compression and leak-down test while all the plugs were out of it.

grapejuice1998
02-01-2009, 05:10 PM
Seeing as how you have plenty of good suggestions to go with already, I would add that I have a lash chart that will make it super easy to set the lash, should you have to go that far.

FWIW, I have had a rocker stud back out on me before. It ran terrible and ticked. I'll keep my fingers crossed for you!