CPS Replaced, No Spark Still......

[Ecomike]

I am not sure which ASD pin numbers, but it would be the 2 pins (female in the harness, with the relay pulled) that correspond to the pins that the relay closes to get things like the fuel pump and PCM all running. Commonly called the output contacts of the relay.

 

[Matthew Currie]

I may be mistaken, but when I had cam sensor problems, I heard various noises when I plugged it back in, and one may have been the fuel pump kicking in. If that's the case, then a dead cam sensor might well also prevent the pump from coming on.

If you have side play in your distributor, I think it's a good idea to get another. My 99 started squeaking when the lube dried up, and galled the shaft (which is why I can't send you my spare one of those). It's not uncommon.

I don't know when the distributor design changed, but the 93 and 95 differ. I think they're interchangeable, but the cam position sensor is different. On the 93, it's buried beneath the tone ring, and you have to take the distributor out and apart to replace it. On the 95 it goes on from the top, takes 30 seconds. If you have a junkyard choice, I'd get the later type. And oh yes, the part in the 93 that failed on me was made by Lucas. Mr Mopar met the prince of darkness at the crossroads and that's all he came back with? Phooey!

 

[MAY POP]

OBDI and OBDII are all interchangeable
http://www.xjtalk.com/showthread.php?t=9111

 

[Matthew Currie]

OBDI and OBDII are all interchangeable
http://www.xjtalk.com/showthread.php?t=9111

Yes, but I do find that the cam position sensor connector differs between the 95 and 99, so although the distributors are the same, and the cam p. sensors functionally the same, you may have to fudge the connector, depending on year. I'm guessing the change came with the other engine harness changes, which means either 97 or part way through 96.

I think, though I'm not positive, that the connector from a 95, which has the late type distributor but the early type harness, will fit the 94 without modification.

 

[ihscoutlover]

I got a replacement distributor yesterday, I'm trying to figure out the easiest way to pull the old one, and pop the replacement one in. Hopefully this cures my issue, and then I can get her started today or tommorrow. Likely tomorrow, since I can't work in these winds trying to keep my hat on and not lose any gaskets or parts/tools.

Jeff

 

[scottmcneal]

Tap the key till the rotor is pointing at 12 or 6 o-clock or what ever time you want it at.Then remove the old one and install the new with the rotor pointing at same spot as old was.I found having the rotor at 12 or 6 makes it easy to set.

GL.

 

[ihscoutlover]

Tap the key till the rotor is pointing at 12 or 6 o-clock or what ever time you want it at.Then remove the old one and install the new with the rotor pointing at same spot as old was.I found having the rotor at 12 or 6 makes it easy to set.

GL.

Then once the dist is in at this setting, then how to time it from there, or should it be exactly where it should be timing wise??

Jeff

 

[Ecomike]

The timing is computer controlled, and not adjustable. There are only about 12-13 teeth, or about 11 wrong spots to set the dizzy, which is why he said to line up the old one and mark the spot where the rotor points, to insure you engage the new dizzy on the right teeth!

"Tap the key till the rotor is pointing at 12 or 6 o-clock or what ever time you want it at.Then remove the old one and install the new with the rotor pointing at same spot as old was.I found having the rotor at 12 or 6 makes it easy to set."

If you install the dizzy off by one tooth it will run, but will not run well. When installing the new dizzy, you need to use a flat blade screw driver to line up the oil pump slot, and expect the dizzy to rotate some as the last inch or so engages, as the dizzy shaft will turn a little as it engages the cam shaft worm gear. IT is trial an error install process!!! Just back it out and retry with a little bit different starting spot, knowing it will twist as the worm gear engages the dizzy on the last inch, until the rotor points where it did on the old dizzy! If you have the right socket, you can also turn the crank shaft at the harmonic balancer nut instead of using the starter motor....

 

[Matthew Currie]

When I've taken out and replaced distributors, I do more or less what Ecomike recommends. Remember that if you miss on the first try you will probably have to use the screwdriver to re-initialize the oil pump slot each time. There's a little bit of forgiveness there, so if you're within a degree or two, it will pop in. The rotor will turn clockwise when you push it down, so be prepared to start a few degrees to the left of your indexing mark.

You can hand crank the engine until the rotor is pointed at something really easy to sight to, like one of the mounting screw holes, but make sure you crank the engine in its normal rotation, or timing chain slack might mess up your indexing. If just taking out and putting back the same one, you can just accept wherever it lands, and mark the case with a magic marker.

When I got mine wrong once long ago, I discovered that one tooth retarded will start and idle very easily but fail to rev up. One tooth advanced may run pretty well but starts hard.

 

[ihscoutlover]

Well I got the old unit out, and I have started to get the new one in, I keep hitting that one spot where it just isn't going in where it should, then disaster:

This dumb arse drops the 6 in 1 screwdriver shaft down, and into the oil pan. Nice, nice. Well after a few swear words, and kicks to self, I have started removing the pan bolts, well all 50 like of them. Anyways, I needed to drain the oil and change the filter, but I was kind of holding off till I got this distributor thing done. I have about 4-5 more bolts to go to get the pan off at least, then I will drop it down enough to get the end of my danged screwdriver out, so I can finish getting the distributor in and the setup done so we can see if I have fire and fuel now.

Jeff

 

[Ecomike]

LOL, I had a similar Dumb Ass episode, after dark, cold, wind blowing, I rushed a two man job by myself on the Saturn Tranny valve body swap (top side install), lost 2 bolts, never did find them again, not under the hood, not on the drive way, not in the grass, looked with magnets and 3 people for 2 days, never found them. One bolt turned out to non magnetic, LOL!!!! I even used a 3 foot video snake to try and find the damn bolts.

They vanished into a black hole, into another dimension, that was 15,000 miles ago, LOL!

Note: I did not pull the tranny for a final anal inspection, LOL! I figured if I could not find them from the top side of the transmission box, the gears would not find them either! And if it self destructed eating a bolt, then I would have a good reason to pull the AT box, LOL. Only way to completely check it was to pull the entire engine, transmission and a bunch other stuff.

 

[ihscoutlover]

Well here is my late but never reply/update. Ok, after the idiots at the rebuild place in MEHICO rebuilt my distributor, well they put some plastic holders to keep the Cam Sensor in the distributor, so when I went to put the cap on and tighten down the screws, well yeah the cap didn't seat right(and I didn't find out why), so I tried tightening down the screws and well they just didn't go anywhere. I had to pull the distributor out yet again. Now those plastic hold on thingys, are jammed in the screw holes, and well I get to take that damned thing back to the parts store and get a replacement. I got the replacement, and I actually got it exactly in where I needed it, so its all back together. Now is where the fun begins. I went to the gas station to get some fuel for the tank, since the gas light was on, and the guage is reading near empty. Humm....well anyways, I put about 3 or 4 gallons in(its a 6 gallon can), and that should have gotten the guage to move up some, well, it didn't even flinch. Low fuel light is on, and it still shows just above the "E" mark. I had to get my portable charger unit out of the utility room and "pep" the battery some, as the temps last night got down into the teens, and the 6-7 year old Red Top Optima just didn't have the crank in it with all the testing and stuff I have been doing. I hooked the battery back up and turned the ignition on, and no check engine light came on, and it wouldn't go into diagnostic mode. I checked all my connections and parts that I replaced. All were good. I hooked my spark plug tester inline with the coil and went ahead and cranked the engine. No spark. I checked the fuel rail test port and a slight trickle of fuel came out. I am wondering now if my ECU is actually fried, or on the fritz or what. I pulled the connector off and checked the connections, and they all appeared good. I disconnected and reconnected the ground connection, and it too was still fine. I went back and turned the ignition back on and still no check engine light. Thoughts and or ideas now? I am considering checking all the harness connections one by one and see if any of those are showing short. I am also considering checking the ignition switch connections and seeing if all of those are good as well. Let me know what else I might be missing, as I have only changed the distributor, coil, and Crank Sensor, so there really isn't much to go from, and since I have the airbox out, I am seriously considering upgrading to the CAI now, since none of the bolts, nuts or parts to hold the factory one down are even there. Ok rant off, let me know where to proceed next.

Jeff

 

[CharlesS]

As the distributor ages the distributor shaft bushings will slowly wear causing the shaft to wobble and in extreme cases; the CPS sensor will rub and short out on the curved trigger plate.
This same problem happened to me 3 years ago....

When measuring the relays internal coil; you can measure across relay terminals 85&86. If the relay coil is good; you should read approximately 73.8 ohms resistance.
To test the CPS (distributor) you can use two paper clips and gently insert then into the harness connector, use a Analog VOM meter and when cranking the engine; you should see the needle swing from 0 - 5 VDC as the CPS moves from the beginning to the end of the curved trigger plate in the distributor. This will indicate a good CPS.

When replacing the distributor it is a good idea to mark where the rotor points before starting to remove the distributor and then as you rotate the distributor housing to remove it; mark where the rotor is pointed when pulling the distributor upward. This will assist you in aligning the distributors drive gear and oil pump notch when reinserting the distributor.
Another item to remember before inserting the distributor.....
You will find a small hole in the distributor trigger plate and distributor housing; these are used for CPS alignment.
Use a tooth pick to align the holes before installing the distributor.
Ensure there is a gasket on the mating surface of the distributor where it comes in contact with the block.
Insert distributor ensuring that the rotor points at the removal mark and twist housing to mesh drive gear and oil pump/distributor notch.
When installed properly....; the distributor base will seat flush with the surface of block and the rotor will align with the mark before twisting and removing of the distributor.

Recheck all harness connectors and ground terminals then verify there are no blown fuses.

 

[ihscoutlover]

Thanks for the advice Charles. The only problem encountered was 1 dropping the screwdriver into the oil pan, and that was solved quickly, but was more time consuming, in having to drop the pan and use my magnet to retrieve it, then put the bolts, nuts and bolts(mostly 11mm, but 4 were 13mm, and get it all back up, and then refill it with oil. It was needing an oil change anyways, I just didn't want to do it until after I got it running and warmed up some. with the battery now disconnected, I await the other computer that is inbound and see if mine is actually the root cause of my problem or not. The fuel gauge is now what's kinda got me wondering if there isn't some other issue I don't know about. I have checked all the fuses under the hood and they are all good. I know there may be some missing in the box under the dash, but even the FSM isn't clear as to what goes where. I was hoping someone here has a '94 owner's manual and could enlighten me on what cavities have/contain what fuses. The most frustrating part is more why isn't what I trouble shot fixed the problem, but instead others seem to keep popping up? Im not looking for the simple fix here. I have learned a great deal, but it seems like I keep coming back to square 1. The distributor only cost me $25, since I had a $25 gift card for parts, and that got used, but I am starting to run low on options here as well.

Jeff

 

[Matthew Currie]

That 93 ECU should be arriving pretty soon, I hope. Let's hope that it gives some answers.

It occurs to me to wonder what the past history of this Jeep is. There have been a lot of floods in various places in the last few years. Could it have been a swimmer? Wiring problems will never cease if it is.

 

[ihscoutlover]

I am almost wondering, however it was near Ft. Smith AR that I got it, and I don't believe them to have gotten any severe flooding, and I have looked at some of the areas of this Jeep and I don't get the impression that is the case, but I could be wrong. The grease is still in the connector to the ECU, so we'll see. I can get more ECU's from the local Pick N Pulls, around me, but I have to make sure I don't end up frying yours too. I don't see any evidence of flooding that you should/would typically find, but since the exhaust was cut out(no muffler) from the cat to the rear axle, and there is mud underneath, well it looks like it had been driven on some dirt roads, I don't find anything out of the ordinary. I will let you know when the package arrives, which will likely be either tomorrow or Thursday, and you'll have a check in the mail. I will post up any other findings, and I will again recheck everything, but all my grounds are showing good, and everything is checking out as it should, I am just frustrated as I want to get this beast going before the snow starts flying. Can a bad ECU cause the fuel gauge to show as it is/does, or could there be an underlying problem with the pump/sending unit assembly??

Jeff

 

[Matthew Currie]

As far as I can see, the PCU doesn't involve the fuel gauge at all, although it, through the ASD relay, does control the pump. I'd check the wiring harness to the pump and sender, and make sure any grounds are good. Pump and sender share a ground, so a poor ground could mess up both.

The gauges in a Mopar era XJ work backwards from what you may be used to. An open circuit pins the gauge, a short drops it to zero. I think that this means if there's a defective ground, the fuel pump will seek ground through the fuel gauge and it will drop the needle.

 

[ihscoutlover]

I will try and see if I can get some work done on it yet today. I had to work early this morning and I still have a couple of scrap runs to make so that I can clean up my driveway some. I will post up my findings, and I will clean and recheck the ground on the FP and sending unit assembly, and verify those are good.

 

[MAY POP]

Check terminal # 9 on PCM plug for 12 volts. That will prove if the Ignition switch is working.Its on the wiring diagram. Unplug the PCM to do the test. I can send more troubleshooting from the Mitchells manual if need be.
Ron

 

[ihscoutlover]

Update. I back probed the wiring for the PCM. I found that the incoming voltage on the #9 pin was system voltage(12V). I then turned the key on, and found that the voltage on the coil feed was beween .01 and .04 volts. But after realizing that I still had my plug tester on the coil wire, I cranked it from under the hood and the blue and white sparks were a great sign. I went ahead and hooked the coil wire back up, and put some starting fluid down the TB, and it fired up, then died pretty quick. Now its not getting fuel. I am going to diagnose the fuel pump circuit and see whats going on there. I got spark now, however I think that the PCM is still acting up. So once the replacement one gets here I have a way to try and see if my PCM is bad or not. That's all for now, and thanks Ron for the advice.

Jeff