Akula69

Forgot to add - we attached the o'scope at both the plug side of the harness and the PCM side of the harness, and the signals were the same...

Don, we used a dual trace scope and did exactly what you described. The square wave from the CPS starts slightly at the end of the CAM's wave when they are in sync. I am unsure but tend to agree with you on the CPS being primary. The square waves are normal until it happens, then the CAM throws an artifact (it is very small spike wave), then after several minutes the CPS throws an artifact, which is a very similar (in shape) spike. The occurrences are totally at random, no discernible pattern. Then, both of them just chill out for random periods of time, then it happens again. the 99 still has the timing marks. Never thought of the timing light - haven't owned one in years....but on the way to get one now.

Thanks Don - unfortunately I left that one out....we replaced the battery with a brand new one. Also left out that we had extensively checked the fuel pump and regulator. The gauge reads rock steady at 47 PSI both parked and moving. The injectors are Mopar, but rebuilt with new O rings and strainers. After the first post we took it for a ride and put about 5 miles on it before it threw the two codes again. Funny thing is, even though the idle is rough the throttle response is smooth all through the range.

Ok folks, got a real head scratcher here concerning idle and ignition. My son's 89 MJ now has a 99 XJ driveline and axles. The only thing that is 89 is the sheet metal, so we are basically looking at a OBDII system. The problem is the engine idle becomes erratic at random times - there is no rhyme or reason to when it happens: at cold start, after running for a couple of minutes, after running for 1/2 an hour, after 5 times around the block - you get the idea. It happens when both at idle or in gear...driving or not. The engine always starts immediately upon turning the key, and when it runs correctly it is dead nuts on 700 RPM and smooth as silk. When it starts the crap, it hesitates several times, then the MIL lights with the two codes, and the idle varies between 350 and 1000 RPM, jumping up and down irregularly. The codes are P0340 - no cam sensor signal and P1391 - erratic cam sensor signal. We have exhaustively worked this problem (for about 4 weeks), and it is truly spoiling his conversion experience. What compounds the issue is the engine ran without this problem in the donor before being rebuilt, so whatever it is, we did it. So far we have: Checked all sensors. Replaced the cam sensor x 2, with NAPA (Echlin). Replaced the crank sensor x 2, with NAPA (Wells). Completely removed the front of the engine and confirmed the timing chain is correct and sprocket marks are in time. Replaced the spark plugs x 2 with champion plugs gapped at .035. Replaced the rotor and cap (Mopar). Replaced the plug wires (Mopar). Replaced the Distributor (NAPA). Removed he valve cover and watched while turning harmonic balancer by hand to ensure the valves are in time with TDC (as piston # 1 is coming up and the rotor is approaching 5:00 O'clock the intake valve is closing; then intake valve closes and as rotor passes 5:00 O'clock the exhaust valve begins to open). Replaced both O2 sensors. Replaced the IAC. Replaced the TPS. Ohmed out the wires from the sensors to the PCM. Pulled the wiring harness and removed all the loom, checked the wires for melted or torn insulation. Did find two of the cam wires had damage, soldered and shrink - tubed the repairs - re-ohmed wires. Replaced PCM with rebuilt one (but removed and sent rebuilt one back when it did not solve problem). Checked the running voltages at both the cam and the CPS - dead nuts 5V. "Cleared" the PCM capacitors by touching the (disconnected) battery cables together for 30 seconds. Used smoke machine to check for vacuum leaks and found none. Hooked up oscilloscope to check square wave pattern for faults on both the cam and the crank sensors. When checked, they are perfectly in sync while the engine is running fine but when the engine starts it's crap they go out of sync. (for those who wonder, the in-sync distributor is 2 degrees out at idle...when the behavior I describe starts the distributor goes instantly to 30 degrees out). I have read that the distributor hold-down fork should not be modified in any way as the ignition timing is controlled by the PCM, but when taken to a local garage (that I trust), the owner states he has heard that modifying the fork (to be able to turn the distributor) has resolved issues such as this....but before I do this I'd like to get input from you guys about the problem. Any and all ideas are welcome....because we are out of options. Thanks

This is gonna sond really stupid (because you already said it was a reverse impeller pump) but, are you sure? I can see how that would push coolant out the tank.

Ryan's does not have one...I mean - the 99 we transplanted from did not have one. The top hose routes exactly like yours around the Sanden 709, including the plastic cover

Well hel!, I didn't know we were being real here! (for the Colorado folks) A bag of sinsemilla, rolling papers and a lighter. (Whoever opens the thing will need it to cope with the future we left them!) (for the California folks) A Spanglish dictionary and a 'Gang signs for Dummies' book. (for the Midwest folks) A bag of pure, genetically unaltered, chemical free corn. (for the Northeast folks) A full gallon can of POR-15, with instructions. (for the Texas folks) A pair of wire cutters and a copy of ' Winning Hearts and Minds' book. (for the Southeast folks) A rubber raft and air pump. and finally, (for the Louisiana folks) Who? (OK - OK, just really kidding Pete...don't slap me!) Jolt cola...havent seen that stuff around here in..7 or 8 years

On the issues: First, we thought the A/C compressor was bad because is sounded like a harpy at the gates of hel!. Unfortunately, after replacing the compressor and recharging the system the daymn thing still squeals when the clutch engages (but strangely not when its off....).We tried loosening the belt and it squeals even more...so tomorrow we'll try tighening the belt. I am concerned about the belt belt being too tight and harming the bearings. Can anyone address how tight the belt should be? I had always thought 1 inch of deflection was good. Second, I believe the clockspring is the horn issue, but have no way of checking the thing. Does anyone know of any tests for that other then ohming the wires? It does Ohm out correctly. Third. we stabbed the distributor so many times in different positions in an attempt to smooth the idle I can't even count. Unfortunately it idles very rough and doesn't smooth out until around 2300 rpm. I am absolutely sure we are at #1 TDC, and the rotor is correctly positioned at 5:00. We have replaced the cam and crank sensor with known good ones. We are getting P0340 code "Loss of cam signal", even though it immediately starts and runs. Any comments / advice is appreciated! .

:agree: Time capsules are supposed to keep treasures from the past, to educate the future. You guys are thinking of a coffin. Bury it once and forget about it after a generation. I :agree: But...it would be education for the future...on who NOT to elect!

Laproscopic or traditional? Think of the stories you can tell!

Thanks - The MJ is down on all fours, and the TC output shaft is fully splined from end to end. I need to check the slip joint itself to ensure it is fully splined on the inside....

OK - on the 89 resto to 99 swap I have a drive shaft question: The application is a 242J TC and a Cryco 8.25 rear The Tom Woods website suggests measuring the rear driveshaft from the back of the transfer case to the center of the u-joint on the differential (specifically: from the front of the rubber boot at the rear of the TC to the center of the u-joint yoke on the differential). In measuring this distance we got 53 1/4 inches. We decided to use the 89 MJ driveshaft, as it is a larger tube and has new u-joints already. I took it yesterday and the company cut it to 53 1/4 inches. They cut it correctly, I have measured it numerous times, both the vehicle and the shaft measurements are the same, but the shaft is still about 3 3/4 inches too long. The TC output shaft mates up perfectly with the slip joint on the driveshaft, and the slip joints are identical from the MJ and the old rear XJ shaft. We are fully engaging the slip onto the TC output shaft. We have measured the output shaft and the inside of the slip joint and the output shaft is fully seating (no internal obstructions). Can anyone tell me why the measurements are correct but the shaft doesn't fit? :hmm: Please - no tape measure jokes...I've tried several measuring tapes and had other folks confirm the measurements.

Yeah - it was most definitely 'Miller time' if there ever was one! Congratulations to Ryan for a job well done.

You stated the noise is cyclical with wheel speed, but could it be an engine component, such as the fan on the alternator or the engine fan itself? Ah..I'm 'assuming' the noise is there at idle with my question.... :doh:

He has now stopped glaring at me. Maybe that's a good sign. LOL - only if he doesn't latch onto your leg when your not looking....

Going to depend on your state Jim. Here in Louisiana you can still do the bond trick. If it's from out of state we have to get an notarized affidavit from the last registered owner proving sale.

Your comment is well thought out and I do agree with you. Pete and the other admins have worked long and hard to keep the "Go look for yourself because you are an idiot" attitudes clearly at bay. As far as anti-social and less tolerant...well, my kids would definitely agree that's me all over.. :yes:

I too have noticed the veteran members slowly "taking a back seat" to the newer, more vocal ones. I myself have stopped posting as much because I tire of members who post the same "stock" answers over and over again without taking time to actually read the post or even personalize the response. While the answers given might be factually correct there is a definite lack of empathy for the person with the problem, which tends to impersonalize the whole issue. Times change.

Separated the backing from the XJ carpet, pressure washed it and it came out fine. Its molded in all the right spots.

at least she has good taste.....

OK - new connectors for the cluster were installed today,,,and we still have 'no BuS' with the existing cluster, :fs1: so now we wait for the replacement cluster.

As Ryan says, we unplugged the "new" BCM first, but during it's initial install I did not cut into the XJ harness, I found that the CCD bus wires (+ and -) actually already appear in the XJ overhead harness plug under the A/C box. Its a simple plug-and-play because the female plug from the ZJ harness is a match to the male plug already on the XJ side - except for the position of the CCD bus wires. (which were re-positioned correctly). Even so, its unplugged now. Even though we did not molest the harnesses for the engine or dash we did check and find good continuity between the cluster harness and the PCM, and the PCM and the CPS, so I suspect the wiring is good. We disconnected all the 5 volt sensors (CPS, MAP, IAC, TEMP, MAT, O2 #1 and #2, fuel sender, oil press sender, AECM...did we forget any?), but were still getting the 'no BuS' indication. After all grounds (except behind the dash) were checked and tightened, the key is turned to run (but not start) and the following happens: cluster displays initial warning light sequences electric (cooling) fan runs continuously ASD relay was chattering continuously (but changing that relay stopped the chattering) Fuel pump runs continuously Although we do have the correct voltages (on the correct pins) at the DLC the OBDII reader powers up but cannot connect for communication.....which makes me suspect one of the following: Ground short Defective PCM We will be pulling the cluster (and possibly the entire dash) tonight to check the behind-the-dash grounds and ensure correct voltage at the cluster connectors. Any other ideas/suggestions/comments are absolutely welcome.

It sucks getting older Pete...... Good luck with the surgery, and hope it solves the problem!

Actually, we did exactly what you mention. After we figured out the vacuum from the filler neck issue (drilled into the top of the 98 Dakota sender and inserted the 92 Dakota sender's vacuum fitting) and the gas tank emission control valve issue (cut the gas vent out of the 99 XJ tank and drilled/inserted it into the 92 Dakota tank). we strapped the whole assembly up to the MJ. It sat too close to the drive shaft for my tastes (due to a frame to cab brace), so we carefully heated the tank with a heat gun and pressed the corner of the tank in to clear the brace. With that modification we now have about 6-8 inches clearance from the drive shaft even with the heat/stone shield in place. The heated spot will be coated with regular JB Weld and will then be covered with a piece of sheet aluminum (in case it rubs against the frame brace). I suspect the tank mod may cost us about 1/2 gallon less gasoline on fill-up. The filler neck is a hybrid between the 92 Dakota tank filler and the MJ, with some changes. First, the 92 Dakota tank has an opening with a rubber grommet side where the tube inserts approximately 3/4 of the way (in its original application). This tube (which is no longer available anywhere except in PaP yards or the like), has a bend in it so it can be maneuvered to place the 2" rubber hose in the correct position for the MJ filler neck. The vacuum "breaker" (designed to reduce back pressure so you can fill the tank quicker) had a straight pipe that needs to be replaced by one with a slight curve (to clear the MJ frame) and then a 3/4" rubber hose connects it to the appropriate place on the MJ filler neck. Because the original was aluminum I plan on using some 3/4" aluminum electrical conduit and bending it with a pipe bender until it is at the correct angle The only thing left is the tie-in of the 99 XJ fuel sender wiring to the 98 Dakota plug (in the sender) which should be fairly easy (4 wires and you already know one is a ground!). We should be installing the engine this weekend, so the real test is coming soon. See the thread here, the tank info is on pages 2 and 3: http://comancheclub.com/topic/38725-89-resto-to-99-conversion/ So, we used: 1) Vent valve from a 99 XJ tank 2) 92 Dakota 22 gallon gas tank 3) Part of the 92 Dakota filler neck 4) Vacuum breaker from a 92 Dakota sending unit 5) 98 Dakota sending unit 6) MJ fuller neck 7) New rubber hoses 8) Eight inches of 3/4" aluminum conduit 9) Fuel resistant flange sealer

I always use Fantastic cleaner, and for the really tough spots I use a small anount of naphta on a rag. Cruiser54 has a lot of knowledge and perhaps will chime in with a better idea. Kerosene...dunno but as you say, I'd spray it down really well with electrical parts cleaner after.