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Wulf711
10-24-2005, 12:31 PM
Now my 2K XJ is still dead. I changed out the Camshft pos. sensor, crankshaft pos. sensor (pain in the A$$ by the way) and the throttle position sensor. Everything is plugged back in and I still can not get this thing to turn over. My final couple of questions before I bring it to a shop or shoot it...

Could 2 bad O2 sensors stop it from starting or would it just run like crap?

Could a cracked head stop it from starting or would it just run like crap? I would think it would be burping smoke and such but....

Any one else have any ideas.... Since I replaced the CKS (crankshaft position sensor it is giving me codes now but just O2 codes....

Bring on the info... Thanks.

Gabe

OverkillZJ
10-24-2005, 12:47 PM
Bad O2 sensor? No. Bad O2 sensor wiring? DEFINITELY! Are you getting spark? Sounds like a sensor might be grounding out somewhere. Remember that Chrysler electrical is the WORST electrical on the face of the planet. It's not going to be fun hunting down the problem...

PassRunnerZJ
11-07-2005, 03:34 AM
My understanding is that you can unplug the O2 sensor (if it is bad) and undo the battery for 3 to 4 minutes so that the computer resets itself and run it that way for a while, you might want to try it. If it runs then I'd look for a short as I ran mine for a few months with the O2 sensor failing.

dasVettemeister
11-07-2005, 04:46 AM
Remember that Chrysler electrical is the WORST electrical on the face of the planet.

Sounds like you've never encountered a volkswagen. Or anything that uses Lucas wiring. (typically british)

PassRunnerZJ
11-07-2005, 11:39 AM
Ah yes, TR7 - Electronics by Lucas "Master of Darkness." Any time on a dark lightly traveled road in the middle of the night. I was passingering in a Ford Pathfinder 4wd van that just shutdown all the electronics in the middle of Utah on the way back from Vegas at night. Coasted to a stop, sat there for a few minutes trying to figure out what happend, then started it right back up and didn't have another problem with it. Aliens???

The codes aren't always the source of the problem, just a starting point. My '01 WJ was throwing codes for all three coil packs, but it turned out to be the seized oil pump & cam shaft sensor drive. When it seized it threw the timing off for the fuel injectors. Have you checked fuel pressure, spark, tried a different battery, verified TDC with the cam sensor possition? Maybe you are off 180 degrees. Just thoughts...

Wulf711
11-10-2005, 01:11 PM
Thanks for the ideas. I still am not sur eon how to check for spark with the ignition rail. I am wondering if I can get my timing light inductor around the ignition rail then try and start it. I should try and figure out the TDC but these new fangled ignition systems are so much harder to diagnose.

Any ideas on the IR would be most helpful. I need to get a new battery for it this weekend so maybe the magic will happen. I am going to unplug the O@ sensors while I am at it, what do I have to lose right now?

Thanks

G

TrojanMan
11-10-2005, 03:43 PM
Have you tried a new battery yet?

PassRunnerZJ
11-10-2005, 05:23 PM
I think that you would have to pull the coil pack off one set of plugs and insert a new plug or two. Find someone to hold it, er um, position it carefully so that the plug(s) are touching the block and have someone crank the engine over.

The way that coil packs are setup and the fact that there isn't a distributor per se, I wonder if it fires both spark plugs at the same time. Theory says that it wouldn't hurt anything if the non-power piston gets a spark as long as it isn't on the way up in the compression stroke. And if say, one and two are 180 degrees off, that makes a lot more sense. I haven't looked at the firing order in a long time so I don't know.

First you also might try lossening up the cam timing sensor shaft and moving it counter clockwise little bits at a time until the wire starts tightening up. I had to move mine about 5-8 degrees counter clockwise to get it to run well after replacing mine.

Wulf711
11-18-2005, 05:51 PM
Have you tried a new battery yet?

I am picking up one tonight on the way home.

Wulf711
11-18-2005, 05:55 PM
Pass... I will try and moving the sensor over a bit. Do you mean the CKS on the bell housing or the CPS on the pump shaft (former distri location)? I will try and get the ignition coil off of it to try with the old plugs that I saved for diagnostic purposes..... All I need to see is a spark from each I guess. The coil packs do run in pairs FYI. I figure with all the info that I have read I could diagnose everyonelses problmes but my own.... GGRRRRR

PassRunnerZJ
11-18-2005, 08:34 PM
The crank position sensor: yes, what used to be the distributor location. Luckily when mine mostly seized--got real tight--it didn't break any teeth on the drive nor tear the wiring that attaches to the CPS as it spun. It sounded like the service dept. sees many with broken teeth when they come on the flatbeds.

Hopefully it will be as simple as either the battery or CPS needing some tweaking. Unfortunately our 4.0 didn't have any reference marks so I can't tell you where to set it or check, but there is a narrow range that it can move due to the amount of slack in the wiring. Hopefully this makes sense. I'll check back later tonight and during the weekend, too.

Wulf711
11-30-2005, 06:17 PM
Thanks Pass. I replaced the battery and that did not do it. I am going to have to play with things a little when the weather works in my favor. The snow, wind and rain has really been a pain in the butt to work on the rig. Maybe you can clarify this issue for me: My FSM says that Camshaft position sensor (CPS) is located where the distributor is and the Crankshaft Position Sensor (CKS) is located on the bell housing. I got the cheap version of the FSM from the web and it is international and also more like a Chiltons manual.... If I move the sensor that is where the distributor used to be how much could that change the timing? I am going to see if there is any evidence of movement then I will try and move it to see. I already replaced that sensor so it should be working.

Gabe

rrubio
11-30-2005, 09:36 PM
I may be way off but is there not a sensor on the tranny(not in the tranny) the acts like a kill switch?If that goes bad it won't crank over.

PassRunnerZJ
12-01-2005, 01:25 AM
Thanks Pass. I replaced the battery and that did not do it. I am going to have to play with things a little when the weather works in my favor. The snow, wind and rain has really been a pain in the butt to work on the rig. Damn, I feel bad for you! Did that quite a few years ago with my FJ40.
Maybe you can clarify this issue for me: My FSM says that Camshaft position sensor (CPS) is located where the distributor is and the Crankshaft Position Sensor (CKS) is located on the bell housing. I got the cheap version of the FSM from the web and it is international and also more like a Chiltons manual.... That sounds correct to me as I have changed or had to change the CKS on my ZJ and the CPS on the wife's WJ.
If I move the sensor that is where the distributor used to be how much could that change the timing? I am going to see if there is any evidence of movement then I will try and move it to see. I already replaced that sensor so it should be working.

I went and re-read the beginning and read that you can't get it to turn over. Does that mean the engine won't turn over or it won't fire up? Either way at this point I would mark where the CPS is lined up and pull the top off the CPS so you can see where the sensor is pointed. Now unbolt and disconnect it and pull it up out of the block. If it starts spinning the housing that you are holding in your hand, then the shaft that drives the oil pump and CPS has seized and the lower section needs to be replaced. (Jeep sells them seperately now as on part may go out, but rarely both at the same time.) After you pull it up and out, look at the gear teeth to make sure they haven't broken. If the shaft spins easily and doesn't try to spin the housing then I doubt it seized, but it is worth pulling and looking at it anyway. Remember don't crank the engine with the unit out or you will need to find TDC and hopefull your manual gives some hint on how to realign the CPS.

My CPS shaft was seized enough that the engine would crank and kind of run for a minute, but then die. Once we pulled it, it would not spin by hand and the new one would. This explained the housing spinning when we pulled the unit. If your's seized more, that that could explain it not turning over or it not starting if the timing is off too much. If it seized a little and spun too far clockwise it will throw off the injector timing, which I understand it what the CPS controls. You could try moving yours counter clockwise about .25" to .5" and see if it makes any differnce as long as you have a reference mark to put it back.

Anyway mine spun about .5" (maybe 7-15 degrees) which threw the timing off and stopped it from running well. When we replaced the shaft unit and the CPS we set it back were it was and it still ran like crap which caused a lot of concern until I noticed the scratches that the lock down tab left. Then we moved it back counter clockwise to where it looked like it was originally and it started quickly, idled, and would accelerate like normal. Fuel mileage and power were better on the return trip from Ft. Collins (which is close to where it died) to Grand Junction so I left it as it was and haven't touched it other than to check the tightness after we got home.

Now that I wrote all that did you check the codes? If you turn the key to ON then OFF three times within 5 seconds and leave it at ON the last time it should give you the code in the odometer display, if it is electronic. If it will not turn over at all and you can manually turn the engine via the crankshaft pully then I would look at the transmission switch that prevents it from starting unless it is in Park or Neutral.

I hope this helps if not PM me and I will send you an email and maybe we can bounce some ideas. -Todd