'05 TJ daily driver won't start
- Thread starter 2005TJdaily
- Start date
How would timing be off? I didn't disturb cam shaft or crank in any way.
Plus the '05 doesn't have a distributor- its fuel injected
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Plus the '05 doesn't have a distributor- its fuel injected
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Ok. You said that you checked compression again and it was way off. What was the compression reading?
Unfortunately, you may have a way more serious problem than a sensor if your compression is way off. Do you have or have access to a leak down gauge? Make note of the low compression cylinders. Remove all the plugs. Take the valve cover off and loosen the rocker bolts so when you pressurize your cylinders it doesn't kick back and move the cam, open a valve and give you a false reading. Pressure test each cylinder and listen for the location of the air escape. if you have low compression, it is absolutely loosing air somewhere. The location of the leak will tell you where the problem lies. If you pressurize one cylinder and the adjacent one is leaking air, you have a head gasket or cracked head problem. This should not be the case for you with the head being rebuilt and a brand new head gasket. Air leak from the bottom up through the block, broken ring or piston. You should not have a bad exhaust or intake valve with a new head, so there should be no noise from the intake or exhaust manifolds. The 97 SE I'm working on right now overheated on PO. I took the head off, the head gasket was obviously blown, but the pistons looked good, but it had almost no compression in #2 and #3. I even bought a new head thinking that was the problem. Then I decided to check the pistons in those two cylinders and they were both badly burned...but it was not visible from the top. If I would have replaced that head, it would have done no good as #2 and #3 were shot. interestingly, I pulled the codes from the PCM and the only code in memory was an Evap purg code, that continued after I put it back together until I replaced the valve. The thing that stumps me is you stated it started and ran fine after the head install, and that it ran hot on the way home but only 4 miles. I should think you would have to run it a lot further than that to burn some pistons, although the 4.0 heads are notorious for cracking. Get that compression problem nailed down, make sure your readings are correct. Hopefully you can redo them and they will be fine, the compression should be dead on with no variations on a new head. Hope this info helps and I hope you don't have bottom end problems.
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Totally helps!
And I did the leak down this morning. 60-80% leak on on cylinders, air Leaking through dip stick- so I'm with you on rings/pistons.
I'm currently tearing down and pulling the engine to do a complete rebuild from the bottom up.
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And I did the leak down this morning. 60-80% leak on on cylinders, air Leaking through dip stick- so I'm with you on rings/pistons.
I'm currently tearing down and pulling the engine to do a complete rebuild from the bottom up.
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I'm sorry. I feel your pain. I sort of lurk on here because I'm a TJ/Wrangler newbie. Not an 4.0L newbie though, seen a lot on the 4.0L 6's on XJ's, I've had my dad's 87 Wagoneer (XJ) for 24 years. Good luck. If you decide to go with a crate motor you may want to hang on to the core for a day or so and make sure you transfer all the stuff, they come with nothing, not even the oil filter mount fitting. Even a small thing like the Oil slinger is no longer available from Mopar, they are cheap but have to be ordered it will stop your progress. One bright side...all the things you replaced will be new once you put it together, and since it had run hot previously, none of that , IMHO, was a waste of money. Put the old CPS back in and keep the new one as spare. Those things have caused me problems on multiple 4.0's, good to have a spare you know to be good. They are also way easier to change on a TJ than they are on an XJ or MJ. Don't loose the bolts, they are unavailable from Mopar and even though they look like a standard flange bolt, they have some weird shoulder that positions the sensor.
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Making progress! All stripped down and prepped for the rebuild.
Turns out the rings definitely blew, and melted to the pistons in some places!
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Turns out the rings definitely blew, and melted to the pistons in some places!
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Probably looked something like this.....grrrr. curious to hear if you sent the bottom end out, bought a reman, or tackling it yourself.
Looks a lot like that.
Didn't send bottom end out, doing it myself. I used a ridge reamer to remove carbon at the top of the cylinders, then lightly honed all the cylinders. Will update with photos as I go along.
Thanks for all the support
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