New from North Dakota: P0303 code and cylinder 3 misfire
- Thread starter Ian
- Start date
Well I just tested my coil pack. Was not easy without someone to turn the key for me but as you can see that's for the 3rd cylinder and it's clearly a spark. My question is what now? I know it isn't a heat thing but I have no idea what to do next.
You're clearly getting spark. So have you wrapped the #3 injector with insulation as was suggested very early in this thread? I had the same #3 cylinder misfire and it took me all of ten minutes from start to finish to cure it by doing that.
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I put the insulator on. The code for cylinder 3 misfire isn't coming back on so that's good. But it still has the P0300 multiple random cylinder misfire and it's still doggy and you can tell it's misfiring when you get on the gas.
Okay so I gave up on this after trying what seemed like everything short of tearing off the head. Brought it to a mechanic today and he said cylinder 3 has no compression and he just had a jeep in with the same problem and it was so bad the guy had to get a new engine. He said he could tear off the head and if it was just a problem in the head he could rebuild it all for 1800. Otherwise a new engine plus install was 4500. I limped it home and tore off the valve cover and saw nothing noticeably wrong. Tomorrow I'm tearing the head off to get a look at good old cylinder 3. Wish me luck.
Thanks for the update!
Let us know what you find once you get the head off. I had to replace the engine in my old XJ Cherokee with a new 4.0. I bought a fully remanufactured 4.0 engine long block for $2200 and installed it myself. After all was said and done, I probably ended up spending around $2800 due to misc parts I replaced while it was out (i.e. alternator). Either way, the price he's asking for a new engine installed isn't that unreasonable all things considered.
Let us know what you find once you get the head off. I had to replace the engine in my old XJ Cherokee with a new 4.0. I bought a fully remanufactured 4.0 engine long block for $2200 and installed it myself. After all was said and done, I probably ended up spending around $2800 due to misc parts I replaced while it was out (i.e. alternator). Either way, the price he's asking for a new engine installed isn't that unreasonable all things considered.
You can buy a remanufactured head for around $400. I did for my last TJ and it worked out well.
http://rover.ebay.com/rover/1/711-5...0001&campid=5337789113&icep_item=272895339617
http://rover.ebay.com/rover/1/711-5...0001&campid=5337789113&icep_item=272895339617
Also, here's a thread I wrote on troubleshooting a misfire:
https://wranglertjforum.com/threads/p0301-the-dreaded-misfire-and-how-i-solved-it.4212/
https://wranglertjforum.com/threads/p0301-the-dreaded-misfire-and-how-i-solved-it.4212/
Did they perform a DRY and a WET compression test to isolate between a head problem or a ring problem? What were the reading for each? Did they do a LEAK DOWN test which tells you were compression is be lost through? What were the results?
Not sure about dry or wet. Got the coolant drained. Belt off, alternater off, working on the power steering pump then the intake manifold. I've been told that's a huge pain in the ass but I really want that head off tonight.
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Anybody know what I have to take off to get to those 4 bottom bolts on the intake manifold? I'm guessing a.c. pump but I would rather not deal with Freon if I don't have to.
You think they're hard to get out, just wait until you need to put them back in and torque them. The easiest and fastest way is to remove the front fender. I've done it several times and it's golden. Leave the headlight wiring connected and just drop the fender. Only a few bolts hold it on and then you'll have direct access to all the intake/exhaust bolts. It will save you hours of frustration for about 30 minutes of work ... REALLY!!!
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How can I take off the front fender and radiator without tearing into the a.c. lines when there's hard a.c. lines attached to it?
I'm about to just throw on my gas mask, open the garage door, cut open a Freon line and run in the house for an hour or so. It's a jeep. I don't need a.c.
I wouldn't ever break the law so I'm not going to to that. Lol. For legalitys sake I'm "having my mechanic friend come over to do it the right way"
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