I just got a call from my fiance who was on her way home. She says the TJ tossed a CEL then started idling rough. Truck drives fine when not at idle, but she said it shakes and "knocks" when she has to stop at a light.
Previous experience tells me its the EGR. Anytime I've had the issue she's explaining its been the EGR. I know you can clean them, but I've never done it. Is this something Seafoam will take care of? If so, can anyone point me to a link on how to Seafoam the intake system of the TJ? I know you can suck it into a vacuum line, can I dont' know which one and how much Seafoam to use.
My buddie is a mechanic, runs his own shop. He said I can pull off the EGR and clean out any larger pieces of carbon that could be causing the EGR valve to stick. Has anyone done this? If so, how much of a pain is it? Does anyone have a step by step list of what to clean?
If its not the EGR, what else could it be? I'll be pulling the codes as soon as I get near the truck. I plan to use the "key on, key off, key on, key off, key on" trick if possible. How many times is it again??
Thanks to all in advance! I need this thing working, its the only auto truck we've got and she doesn't know how to drive manual!
My fiance said she got in the truck after work (it drove fine to work) and it started and acted fine. When she came to her first stop light the truck started acting funny. She said it was shaking and knocking badly, but once she was not at idle the truck would act fine.
Also, by the time she got home the truck was running fine, although the CEL was still showing.
I drove the truck around a bit once I got home, and the truck didn't seem any different. I thought at one point I felt some *minor* chugging, but it was so minimal it could've just been the road.
I also found out what P0441 is...
P0441-EVAP Emission Control System Purge Flow Fault
Does anyone know what could cause a rough idle/knocking and trip this code?
EGR - Exhaust Gas Recirculation. The 4.0 does not have an EGR Valve per se - the cam is ground such that it leaves a tad of exhaust gas in the cylinder, controlling NOx.
I'll bet she not telling, or didn't notice it backfired. The backfire blew the Evap vacuum hose off. Look closely under the master cylinder and at the intake manifold - look for a hose that fell off.
Simply put it back on. It'll run better and the CEL will eventually go out.
I got that it has not EGR, someone already posted it.
No CEL, went off on its own, and after 95 starts no CEL anymore. The EVAP codes are ghosts, confirmed by a stealership. The fiance knows what a backfire is, it never did unless there was a silent one...
According to the stealership, "the misfire was just a random fluke that can happen to any vehicle, and we probably will never know the real cause."
We've also got "low oil pressure in the cylinders. its suppose to have a minimum of 13psi, but we've only got 8psi."
I'll be starting a thread about that shortly...
Thanks for all the help guys!