mechanical yes........IGN timing no........

 

here is what the actual jeep dealer wrote about what they did.

"complaint-- check engine light on/running bad
just had head and gasket replaced/jut had oil pump replaced/had plug and wires replaced


cause
compression tested and leak down tested
checked spark and fuel/ok traced wiring for injector #4/all ok/checked
asd output ok/checked coil wiring/ok/switched injector 34 with #2/ removed valve cover/checked push rods/ok
rotated engine/ehecked valve springs and found exhaust valve at cylinder #4 not opening very far/ poss worn cam/engine has very low oil pressure"

i'm heading back out to put the valve cover back on and fire it up in the dark to see if anything is arcing then i think i will put a new coil and rail on it in the morning to see if that helps. whats weird is other then the miss the engine sounds great there i absolutly no knocking or ticking of any sort.

 

true, ignition timing is critical but he was told he had a dead cylinder. all showed 110 to 115 psi after compression test. if ignition timing was off it would effect all cylinders, dont you think?

 

i was just talking about the old saying.........

 

not bashin bro. lookin for confirmation, i'll be the first one to admit if i'm wrong.

 

rotated engine/ehecked valve springs and found exhaust valve at cylinder #4 not opening very far/ poss worn cam this to me says the problem is here. double check the valve lash adjustment. it seems unlikley the cam all of the sudden went bad. maybe the guy got it wrong when he adjusted it.

 

ok from what i found to adjust the valve lash put the cylinder at tdc and tighten each bolt to 19-21 ft pounds? is that correct because that is what i did tonight. i just had it running from a cold startup it had 40psi oil pressure still idleing rough but when i tach it up to about 2000 rpm it seems to smooth out.then i pulled the coil rail and checked the plugs to be it doesn't look like the number 4 plug is fireing. does anyone know if there is a way to test the coil rail? a new one is 140 bucks so i hate to just buy one as a test but i'm really thinking this is a spark issue. and another thing i noticed after taching it up is that the exhaust smells rich so that also makes me think spark issue.since it would be putting raw fuel into the exhaust.

jason

 

No adjustment on the Factor Pedestal Rockers...they are torqued down and forgot about..........this is for ease of instalation at the factory.

 

ok i just replaced the coil rail and it's still missing and pulling the p0304 code (cylinder 4 misfire) i also unplugged the no4 injector with it running and there is no difference in sound or rpms.of course i forgot to bring my ohm meter with me so i can't check the voltage to injector but i'm assuming the injector is good since the dealer swaped it with the no 2 cylinder. any ideas?

 

you may have a issue with a Injector cricuit in the ECM...Also there have been several issues with injector harnesses lately. I think autozone may have Noid lights as a rental tool.....You should always have a constant Hot source to the Injectors...They are pulse Grounded thru the ECM. Check it out let us know........

 

found a volt meter and i do have + 12 volts to the injector but i'm not seeing a ground but since it's a digital meter i'm thinking it might not be registering fast enough during the injector pulse. so i have a set of noid lights on the way to find out for sure.if not i'm at a loss and running out of time quick. like i said the exhaust valve doesn't look to opening as much as the others but i can't see that pulling up a code.i took it for a drive and it doesn't seem to be lacking any power at all but at idle it still only has 10 psi of oil pressure but has about 40 while driving it.

 

got the noid lights and it's flashing so it's not an injector wiring problem. so i'm lost now.it's not stalling at all and only runs rough at idle then runs good as soon a i hit the gas so i guess i'm just gonna let her drive it and plan on replacing the engine once it starts running worse. the cam does show signs of wear so maybe thats the whole problem.too bad i can buy 1 ratio rocker to get that valve opening further and see if the code goes away.other then that i'm clueless.

 

i hate to say this. but your wastin time and money. not trying to sound mean it is what it is.

the cam lobs are worn. and the oil pressure going down is bad bearings. usually crank bearings. trust me i just dealt with this i got a used 500 dollar engine with 71k miles and put it in i suggest the same.

 

have you pulled the wire connector off the #4 cylinder to see it the tone changes?

 

only the injector wire and no the tone didn't change at all. it doesn't have plug wires so can't just pull 1 at a time. i did however do a half assed fix that made it a little better. since i know the cam is just about shot i changed the push rod to one that is just a little bit longer (less then an 1/8 inch) and put it on the no4 exhaust valve and now the idle smoothed out a little bit and the cel hasn't came back on yet.this thing still has all kinds of power i drove it about 30 miles to get it good and hot. and while driving the oil pressure stays about 20-30 psi but when you stop and let it idle it drops to about 10psi still. i think she is going to be putting it on craigslist and just find somthing different.so if anyone is looking for a jeep with a new head,coil pack,and oil pump and a questionable engine let me know the body is just about perfect i don't recall seeing any rust on it at all