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  #31  
Old June 23rd, 2013, 22:48
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Ecomike Ecomike is offline
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Re: diagnosing engine vibration

"
Quote:
OK, so while I'm waiting...(I can't believe you people don't sit by your computer waiting for me to have a problem)..
LOL!!!

I read an old thread with a similar story on the gears, I think you are OK, but I am not the expert.

The gas on the plug is the clue you need to follow. Is it just one plug with gas ? If yes, the spark plug, the secondary wire to that plug or the injector is likely the problem, or all of the above assuming the compression is good.
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  #32  
Old June 23rd, 2013, 23:11
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Re: diagnosing engine vibration

Yeah, I kind of skipped over it because the cap/rotor/wires were all brand new during the rebuild, so I took it for granted that they were good. But then again, they got introduced at the same time as the problem.

As for the #2 cylinder, it seemed to be the only one. I pulled all the wires off and put them back on, not necessarily the same way because they seemed to fit better this time. With each wire I made sure it popped all the way on and spun it around a little to get a good contact. Started it up and it backfired and sounded like it wasn't running on all the cylinders. Popped off the #1 plug and fired it up; it ran worse. Pulled the number 2 plug and fired it up, no difference. Plugged it back in, fired it up, ran better...but as I mentioned, I started hearing noises in the tranny with no fluid so I shut it down. It has to come off to replace some seals in the front anyway.
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  #33  
Old June 24th, 2013, 09:22
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Re: diagnosing engine vibration

I think if the Tran fluid is low enough, they can make noises. I think I have seen that with other vehicles several times.

I would test the plug wire with an ohm meter, compare to say #1 plug wire, replace the spark plug, or swap #1 and #2 plugs. Check the oil for gasoline odors now. Then if they are both good (and if compression is OK, might test it any way, might have damaged rings since it is new, or overlooked something in the build, this is a new-rebuilt engine?)

Then if those are all good, get a new injector, as it sounds like the injector is leaking, not closing and sealing completely. A fuel pressure test for 10 + minutes, install the gauge, run the engine, power down and see if the pressure holds might confirm a leaker first.
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  #34  
Old June 24th, 2013, 10:10
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SanDiegoXJ SanDiegoXJ is offline
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Re: diagnosing engine vibration

Yeah, it's a newly rebuilt engine. I have about 2500 miles on it. The vibration has been there since the rebuild, but each time I was able to find something, like a loose nut on an engine mount, a trashed transmission mount, switch from poly to rubber, and with each move, the vibration got less and less. The mechanic that rebuilt it swears it isn't an engine problem.

The #2 plug only got wet since I moved the distributor this time around. I moved it back one tooth, tried to run it but it had no power. Then I moved it back to it's original position and started to verify that everything was back to normal. But it didn't run like normal, it ran like crap, like it had a misfire. I think the only reason it's wet is because the plug wasn't firing at all. It hasn't shown that symptom since the rebuild, and removing the plug wire from the plug and reinstalling it seemed to fix the misfire issue.

But that also got me thinking that if a plug wire is that sensitive, maybe one of the internal connectors isn't the best.


...so I just pulled the ohm meter out:

Coil wire - 0 Ohms
#1 - 0 Ohms
#5 - 0 Ohms
#3 - 0 Ohms
#6 - No reading
#4 - 0 Ohms
#2 - No reading

By no reading, I mean when I hit the electrodes to the opposing sides of the plug wire, the guage didn't budge while the others bounced off the 0 Ohms side.
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  #35  
Old June 24th, 2013, 10:14
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Re: diagnosing engine vibration

well, tested a third time and they all got readings =(

The two that didn't give readings initially, now give uneven readings though. The other 5, I can move the needle all around and it stays at 0, but with the two in question, depending on where I'm hitting it, it can be 0, 100, 200, or just no reading at all.

So I'm back to hoping bad plug wires.

new cap, rotor, wires, and the A/C replacement pulley should all show up this week and I can slap it back together and try more stuff.

Last edited by SanDiegoXJ; June 24th, 2013 at 10:29.
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  #36  
Old June 26th, 2013, 21:32
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Re: diagnosing engine vibration

Just to update the thread, in case anyone finds themselves in my predicament...

http://forums.off-road.com/jeep-shor...ignment-2.html

This may be the thread Ecomike was talking about, but it seems it's not so uncommon to have timing gear marks 180 degrees out.

Current state of Jeep:

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  #37  
Old August 25th, 2013, 16:24
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Re: diagnosing engine vibration

OK, so I did enough research to find that it wasn't uncommon for the points to be 180 off, so I ditched the timing issue. Then it became a tranny issue. I put the engine back together with new 8mm plug wires and a summit cap/rotor and all new gaskets. It looks much prettier! =)

So off to my previous concern, the vibe was caused by an improperly indexed torque converter....after all, I knew from the mechanics own admission that he didn't index the TC when he removed it.

I get the tranny almost all the way out and am having problems getting the dipstick tube out...so I stick some vice grips on it, lightly tightened so it catches the lip on top, and give a good yank, and off she comes. Now the TC/flexplate bolts are out, all the electrical connectors disconnected, tranny and t-case linkage disconnected, and the only thing left is the last 4 tranny bolts. So I break loose the 5/8 bolts on each side and then configure my jerry rigged 3' extension, including several 10" flex extensions and a bit of duct tape along with my newly purchased E12 socket. But for some reason, I can't get the socket to engage with the bolt, it just keeps spinning freely. So I reach my hand up and try and get just the socket on. Dontchaknow, the damn thing wasn't even finger tight, it was sticking out by about 4 or 5 threads...so I go to the other side, same damn thing. Guess the mechanic forgot to tighten those.

so I yank the last four bolts and go to pull the tranny, but something is stuck...turns out there's one more bolt that mounts from the dust shield to the tranny on the driver's side. so I get that out, and out comes the tranny.

then I look at the flex plate....it doesn't look like all the markes from where the TC mount are equal...by that I mean, two spots you can see the entire outline of the TC mounting block, another shows only partial, and the final, you can't even see it. =(

I'll get pictures later, but I've resorted to heavy drinking for now...
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  #38  
Old August 25th, 2013, 16:27
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SanDiegoXJ SanDiegoXJ is offline
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Re: diagnosing engine vibration

one question though...since the flexplate was kind of funky, and the holes look a little wallowed out, I was going to slap in a new flexplate since it's already exposed and pretty damn cheap. My question is, if I put in a new flexplate, does indexing even matter anymore?

and what if I get a new TC as well? I've heard a miss can screw up a torque converter over time, I've been driving for two years with the dang thing improperly mounted, I'm thinking it's trashed.
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  #39  
Old August 25th, 2013, 16:53
joe_peters joe_peters is offline
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Re: diagnosing engine vibration

To be honest with you, I am OCD and mark everything when I take things apart, but as you point out, when you replace an item with a new part you have eliminated any index markings.

Just go for it.
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  #40  
Old September 10th, 2013, 20:19
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SanDiegoXJ SanDiegoXJ is offline
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Re: diagnosing engine vibration

OK, so just to bring folks up to speed...

Once the TC was off, I realized the wear pattern on the flex plate from the 4 pads wasn't even and the holes in the flex plate appeared to be wallowed. So I got a new ATP flex plate and got it installed. I also yanked the torque converter off to change the front pump seal, and looking at the torque converter, you can see multiple grinding marks, as well as burned marks and feel grooves in the metal.

So now I've got a Pro-King J30 TC, new bushing, and new oil seal on the way from O'Reilly's.

Anyone have anything else I should be looking for while I'm in it?

Last edited by SanDiegoXJ; September 10th, 2013 at 20:26.
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  #41  
Old September 10th, 2013, 20:30
Peteyg Peteyg is offline
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Re: diagnosing engine vibration

So uh....Torque converter.....I said it first! Glad you found the problem.
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  #42  
Old October 3rd, 2013, 15:29
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Re: diagnosing engine vibration

It's hard to say what's causing/caused it.... Ishould have it back together soon...hopefully by this weekend. But the top two bolts on the tranny weren't just loose, they were backed out almost a 1/4 inch, so the tranny may have been flopping around. As the tranny moved around, since the TC was bolted to the flex plate, it became the pivot point, which is what caused the grooving and funky wear on the bushing. If that's the case it didn't cause the vibe, it was just destroyed because of it.
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  #43  
Old October 4th, 2013, 20:21
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Re: diagnosing engine vibration

Hurry up and get it back together! I've had the same problem for a while. Vibration at 1750. Nothing at highway speed. I had issues with trans bolts missing and the starter falling off. Then it would die when I shifted into reverse. Bad / weak CPS as the trans was twisting when I put it in reverse and the bolts were missing on the trans to engine.

I did the same stuff you did with injectors, plugs, wires etc. Haven't indexes the distributor (that was my next thing).

Good luck.
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  #44  
Old October 5th, 2013, 12:21
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Ecomike Ecomike is offline
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Re: diagnosing engine vibration

" But the top two bolts on the tranny weren't just loose, they were backed out almost a 1/4 inch, so the tranny may have been flopping around. As the tranny moved around, since the TC was bolted to the flex plate, it became the pivot point, which is what caused the grooving and funky wear on the bushing. If that's the case it didn't cause the vibe, it was just destroyed because of it."

I am going to disagree with that. It is an obvious place and source for vibration in the driveline, and the CPS is mounted to the Trans bell housing, so if the flex plate is moving and vibrating the CPS sensor may not see the flex plate teeth all the time causing a partially defective CPS timing signal causing an engine vibration from poor ignition timing that comes and goes at a high frequency.
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Quote=8Mud: "Go ahead and put up the best fence you can build, I'll bet on some Mexican with a few dollars of nails and a pile of scrap lumber."
34 MPG , '85 2WD Cherokee Pioneer with custom installed, 64 hp, 2.2 L Nissan SD22 Diesel 5 spd Manual; & 4 Renix XJs, '87 Wagoneer 4.0, 4WD, 89-Cherokee, 4WD, '87 Cherokee 2WD, & '89 Cherokee Pioneer 2WD, all 4dr. #2091
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  #45  
Old October 5th, 2013, 22:19
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Re: diagnosing engine vibration

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Originally Posted by Ecomike View Post
I am going to disagree with that. It is an obvious place and source for vibration in the driveline, and the CPS is mounted to the Trans bell housing, so if the flex plate is moving and vibrating the CPS sensor may not see the flex plate teeth all the time causing a partially defective CPS timing signal causing an engine vibration from poor ignition timing that comes and goes at a high frequency.
Hmm, not sure if we're saying the same thing different ways or different things altogether...

What I was implying was that the torque converter didn't cause the vibe, the loose tranny bolts did. The damage done to the torque converter snout and bushing was then caused by the tranny vibration...

Anywho, it's all back together, but it' ain't running at all now. =(

It started up, ran like hell for a couple secodns...

Pulled the distributor, tried to reseat it a tooth back, and now no spark at all. =(


Not sure if the cps just went kaput or what. Is there a way to test those?
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