4.0 Engine swap complete but won't start... Please Help!!
Did an engine swap and had to switch the oil drive unit and cam sensor from the old motor to the new, now I can't get the motor to run. I used a compression tester to find the compression stroke on the #1 piston, turned the motor until the timing mark on the balancer lined up with the mark on the timing cover. Lined up the holes on the drive unit with a toothpick, just like the manual says. Dropped the drive unit into place and everything looks good, but it still won't start, it will stumble and stutter and act like it wants to but just won't. Plugs are wet, so i know I'm getting fuel. Wondering if maybe somehow it jumped a tooth on the timing chain? Any way to check the timing w/o tearing it apart and looking at it? Any suggestions?
FYI... jeep is a 99 WJ, new motor has 52k and is from an 06 TJ. Also, there are no engine codes. Also has a new crank positioning sensor and cam positioning sensor.
11-14-2013 08:53 AM
Sounds like it is out of time. If it were me I would bring up the timing mark and remove the cam sensor from the engine and rotate the mark around again and reinstall the cam unit. I know you said you used a comp tester to check the stroke but it does sound like it could be out 180 degrees and this is fast and easy to try.
11-14-2013 08:55 AM
That what I was thinking too. The jeep is in our shop and not at my house, I am gonna try and get over there tonight and work on it for awhile. Hopefully that's all it is. I will let you know if I get figured out.
11-14-2013 11:42 AM
x2 on running through the cam sensor install again.
Once you get it running you need to have the fuel sync set with a drb3. The cam sensor runs the fuel sync.
THIS IS VERY CRITICAL, YOU CAN RUIN YOUR ENGINE IF YOU DO NOT DO THIS!
If you want i have some e-mails from when i built my stroker that i can send you that are a good walk through on this process.
11-14-2013 12:46 PM
This is exactly the swap I did into my '99. I have seen it done many times - installing it 180° off.
Did it work out for you?
11-14-2013 07:21 PM
Well, I was able to work on the jeep long enough to walk through the cam sensor install again. I had to roll the motor over several times to get it to even come close to where I thought the sensor should line up at. I did get it to start after I got it lined up. It runs very, very rough. I have to give it a little gas to even keep it running. I did notice that it runs better if the vacuum line going from the back of the valve cover to the air intake is unhooked, I checked the line and there is no restriction in it, why would this be? I am also now getting DTC P0622 and P1391. I am guessing the P1391 is probably because the cam sensor is out of adjustment, but should it run this rough? Could the fuel timing still be off and if so is there enough adjustment to get it set right once I hook it up to the DRB3? As far as the P0622 code goes, it didn't throw that code before the motor swap and I haven't even looked that code up yet. Thanks again for all the help so far.
11-15-2013 07:19 AM
You can slowly rotate the sensor while it's running to see if the idle issue is fixed. To dial it in perfect you'll need a DRB, I don't know why but I remember 6° as being important, maybe that's the most out if sync it can be...? I can't remember, maybe I'm just crazy. The rough idle can just be the computer relearning, unless it's really bad of course. I can't look up the other code right now so over you do let me know what you find.
11-18-2013 08:23 AM
Update- Still not running. Was running but only when I had my foot on the gas. Wants to backfire out of the throttle body. I tried unhooking the battery over night to reset the PCM, still no luck. I have reset the cam sensor numerous times, it seems like a straight forward process, but am I missing something? I followed the FSM exactly, my only question is I don't find a "timing scale" on the timing chain cover, I can find a mark, and I assume it it's right but not sure I guess. I will post a pic and hopefully someone can let me know if it's the right one. If it is any other ideas?? TPS measures good, coil rail measures good. Jeep ran and I drove it into the shop before I swapped the motor out (it had a rod knocking), just trying to figure out what I'm missing....
11-18-2013 08:26 AM
Also should add, I am not getting anymore DTC's. I have a spare PCM that I tried also, it does the same with both PCM's, would only run if I kept my foot on the throttle, and even then it would cut out and RPM's would bounce all over.
11-18-2013 01:48 PM
Are you using the intake/throttle body/ignition/coil pack/etc from the WJ, or are you using the TJ parts?
I would use ALL the WJ stuff, or you'd be inviting differences.
11-18-2013 02:04 PM
I am using the coil rail and throttle body from the WJ. Intake is from the TJ, I drilled and tapped a hole for the IAT sensor.
11-18-2013 03:56 PM
I guess the only other thing I can add is that I do know that 05-06 TJs had issues with the OPDA, and the drive gear on the cam. Even at only 52K, I'd check to make sure your cam gear isn't wiped out, which would make your timing incorrect. Did you see the TJ motor run that you got?
11-18-2013 04:12 PM
Unfortunately, I did not personally see or here the motor run. I will say it came from a very reliable source though. (For what it's worth). I did inspect the old oil drive pump that was in it and the gear looked good. I looked down the hole in the side of the block and the cam gear looks ok, doesn't look broken or worn. I originally changed the oil pump drive because the cam sensors are different.
11-18-2013 04:31 PM
Ok, in that case I'd leave it be. I doubt that she jumped time at the chain --- i've had 4.0s go 240K and not have timing chain issues, so I personally would doubt that.
I guess I'd stay focused on making sure the timing is right, and that everything else got plugged in ok, all grounds are ok, etc. Sorry man I can't be much help. :(
11-18-2013 04:40 PM
remove fuel pump fuse/relay, check spark for all cylinders, if spark is there, check ign. timing by timing ignition light.