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Ok well I will have to check for codes when I go to look at it. Really hoping it has a code to help pinpoint the issue. If there are no codes what all should I look at?
Well i sure hope its not that. How expensive was that fix?
Not too bad at the time. I bought 2 rebuilt heads for I believe 400, but that was 2016. I did the water pump and timing stuff too. It had low compression on #1 cylinder. It would miss idling, then smooth out once you took off. I didn't have a garage at the time, so I just bought rebuilt heads and took it to my dads house to fix one weekend. If you had time too take it apart and wait a good engine machine shop could fix a head cheaper than you could buy it.
How did you boil it down to a burned valve? I would really hope that if I bought this truck this would not be the issue. I have a tendency to buy "bulletproof" motors and have them be a lemon for me. My Jeep 4.0 had/has issues.
Check compression. And if the exhaust is decent you can do the dollar bill test. Hold a dollar over the tail pipe, if it tries to suck the bill in the pipe then an exhaust valve is leaking.
How bad it is to drive with a burnt valve? Can't you unplug that injector? Also did yours only misfire at idle?
I drove mine for months, it only missed at idle.
Well I guess I will have to see how bad the miss is and go from there. I would really hope a tune-up would solve the issue.
Be cautious cuz it's the same bull crap that guy told me when I bought mine. I figured it was more than just a Miss but I was looking for that particular truck at the time and it was the only one I could find. It's getting really really hard to find one in any kind of good shape
Yea people right now are asking premium prices for rusty ****boxes. The price of this one is fair if it's as rust free as he says. Even if one of the heads needs work then I can still justify it because of the cost. Also, if I bought an extra junkyard head and took it to a machine shop to look over, would it be safe to swap that head in if the shop finds no issues? Basically is it OK to only replace one of the heads?
You can, but I wouldn't do just one. You're already that far in, might as well do it. Remember to fix the plenum gasket too while you have it off.
Well you have been very helpful. Even though I REALLY hope it wouldn't be anything like that I guess its best if I am aware of it. Luckily if I buy this truck I can sell my Jeep for about $1500 more then the price of the truck. So that could help if it's something worse then I want it to be.
I had a 99 XJ with a 4.0 before I had this truck. Only got rid of it because the body was rusting out
Yea I am getting rid of my Jeep mostly because of rust. The PO of my Jeep hid a ton. Painted over every spec of rust. Not to mention he sold it to me with a cracked head and never told me about it. Motors for those are so cheap I should have just bought a whole new motor instead of fix the lemon of a 4.0 that it had. That's why I am weary of buying a truck with possible engine issues.
That's basically how I got mine. I was working on a truck for a guy and that's how he paid me. But I figured the head was messed up when I got the Jeep. I knew he had overheated it. Jeep engines are expensive out here
Yea I can buy a used good running 4.0 for dirt cheap where I live. I should have done that instead of buy a reman head for about the same price. I would have offered like $700 less for the Jeep if I had spotted these issues beforehand.
I am now reading stuff where these magnum heads crack very often. So.... that would suck. Would that cause a misfire? How common is this?
