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bakelite
06-14-2006, 03:55 AM
Air filter full of oil....take off oil filler cap, tons of suction into engine..PVC valve is good...4.2 Jeep 89...was gonna put a new motor in but local mechanic says motor is good it's a ventilation problem...???? all the shops are too busy. Gonna cut the cat off tomorrow and try that. Starts great, runs not too bad. Any ideas?

Freaking lines and hoses everywhere even one to the cat...or was one there anyway. Could exhaust be coming back into the engine, there is another line on the exhaust just below the exhaust manifold...I'm confused. [15] ECR??

Fuzzydog
06-14-2006, 08:24 AM
Hey, Joe - had the same prob on my 90 4.0 - Very wierd as it felt like there was good vacuum in the line from air box to valve cover but would always fill with oil and make a mess. I finally went to the jeep dealer and got a new set of pcv lines and no probs since then. I also took off the valve cover and cleaned the inside but it wasn't bad and I don't think that helped any at all.

Good luck with that.

Oh, yeah, I also had some idle wierdness before which was due to oil getting all over the TPS. cleaned that up too when I was done.

bakelite
06-14-2006, 08:32 AM
Thanks:) .... wierd that the valve cover is sucking air yet the air cleaner gets full of oil, like the bottom end is pressurising, I thought I holed a piston. The 4.2 is different than the 4.0 though, there is so much crap on this motor....anyone know of a site that shows you what pollution crap you don't need on the motor? [cheers]

Fuzzydog
06-14-2006, 08:41 AM
Sorry - wish I could be more help.

Hey are you around late friday afternoon? I'll be passing through on my way to the Okanagan....about 4 o'clock?

bakelite
06-14-2006, 08:52 AM
hey I appreciate any help...[15] ...I'm dumb. I should be, probably be outside or in the shop, be nice to see you, I'll try to stay awake around then. [cheers]

Jeep eh
06-14-2006, 11:30 AM
blow through the pcv hose and make sure its not plugged

Nutbar
06-14-2006, 12:51 PM
Hey Joe

I thought you were the one that posted the link to the 4.2 electronic carb bypass, once you have done that you can pretty much eliminate all of the pollution crap, and as far as the oil in the air filter goes try running a new pcv hose straight from the carb to the valve cover the original one has a bunch of connections in it one of which is a restricter hole get rid of all those conections and the restrictor

Dieseljeep
06-14-2006, 12:54 PM
Try running a vented oil cap and run the PCV hose into a a catch container like an old oil bottle that has lot of room around the hose going into the neck.

Make sure all the hoses aint plugged and the inside of the valve cover is clean and the oil passages aint filled with oil sludge ,try running an engine flush or auto tranny fluid (dex2-3) before changing oil.

bakelite
06-14-2006, 02:37 PM
I know Mikey just happened to find that. I will try it, I was sure the motor was nfg but now I looked into a rebuilt engine the mechanic says it's just the PCV so I changed that, no change. Took the air filter off and the smoking cleared up right away. I don't understand what could cause the vacuum like pressure in the valve cover. I'll try that stuff tho, gonna remove the cat too, the exhaust looks real old, needs replacing anyway. Be nice to get rid of all the hoses and crap. lol. Thanks guys I appreciate the help, not much of a mechanic here....obviously [15]


Really..thanks [cheers]

Gaybait
06-14-2006, 06:04 PM
hey fuzzy, ( sorry to jack thread ) i havent had a tune up in forever and mine does that too, after its good and warm ( my 87 4.0 ) it sounds almost like a backfire then my idle goes up and down and up and down when im just sittin there doin nuttin.. So Oil onthe tps eh?

bakelite
06-14-2006, 06:14 PM
Just messing around with this piece of shit...took off everything I could anything that sucked I plugged it, ran the pvc to the carb, the electrical connection to the carb had already been removed, put it back on, no change, took it off, went for a drive...seems not too bad, hesitates when you first accelerate, revs to 4 grand no problem but I got no air cleaner on, the rear hose on the valve cover is sucking air like crazy, if there's vacuum in the valve cover would the pvc valve work anyway? What could cause this vacuum, my manual doesn't say shit? (Haynes[16] )

Fuzzydog
06-15-2006, 08:38 AM
hey fuzzy, ( sorry to jack thread ) i havent had a tune up in forever and mine does that too, after its good and warm ( my 87 4.0 ) it sounds almost like a backfire then my idle goes up and down and up and down when im just sittin there doin nuttin.. So Oil onthe tps eh?

Hmmm.. mine actually just would idle really high - like 2-3k, then slowly come down to normal. I don't know about the up/down thing but from experience with other vehicles this sounds like it might be an oxygen sensor issue.
the TPS really is not hard to take off, it's on the side of the throttle body held on with 2 torx screws. Might be worth taking the time to remove and clean anyway - just spray it with some fuel inj system cleaner (formerly known as carb cleaner)

I guess the first thing is - do you have oil in your airbox?

bakelite
06-17-2006, 07:52 AM
Try running a vented oil cap and run the PCV hose into a a catch container like an old oil bottle that has lot of room around the hose going into the neck.

Make sure all the hoses aint plugged and the inside of the valve cover is clean and the oil passages aint filled with oil sludge ,try running an engine flush or auto tranny fluid (dex2-3) before changing oil.


Holy crap I took the valve cover off last night and there is so much sludge in there...can't believe it ran. I cleaned out as much as I could with a little brush and my shop vac, flushed the motor twice with atf, got oil all over everything...[15] .... then crapped out, gonna put it together again today, it actually sounds better already. Got another new PVC valve and oddly enough it looks nothing like the last new one I got, new rotor, cap, plugs..if it don't work better today I'll cut the cat off, if that don't work, I'm stumped, take it to a shop I guess if I can find one that ain't screaming busy doing oil changes and shit. [cheers]

bakelite
06-21-2006, 03:03 PM
[27] if it was a bike I would say someone put a ring in upside down. Changed everything I could thing of, 3 plugs oil soaked and black soot all over them, one plug the electrode bent over so no spark on that one, 2 plugs light brown and covered in crap. Lifters are noisy as hell so some of them are shot. Still creating a steady vacuum in the valve cover, smoking like hell, but it's weird driving it, anything above about a 1000 rpm it runs like a champ other than the smoking, had it out on the highway ran it up to around 4000 rpm, about 130 k...lots of power...doesn't heat up...I can't figure anything else out on this, driving me nuttier [15] Time to pull it apart I guess. Thanks for the ideas...[cheers]