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TJ misfiring

ItchyDong

Airframe & Powerplant LJ Mechanic
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Ok, I went out and wiggled wires, then I figured, what the heck, I'll try unplugging the injector wires. Well, I unplugged the first one and didn't notice any change what so ever. Plugged it back in and unplugged the next one, and there was a definite change. I took a video but you really have to listen to hear the change. I can hear it better with my ear then I can on my phone. The phone pics up the fan noise making it harder to hear. Anyway, I think I may have a bad injector?

Good lord. I read through this whole thread wondering when the hell someone was going to quit pissing over the spark plugs and mention the injector. Check for 12 volts and injector pulse on the ground wire to actually isolate the injector. If both of those are present, try tapping on the injector while its running.
 
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KimsJeep

KimsJeep

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Good lord. I read through this whole thread wondering when the hell someone was going to quit pissing over the spark plugs and mention the injector. Check for 12 volts and injector pulse on the ground wire to actually isolate the injector. If both of those are present, try tapping on the injector while its running.

I stopped at the parts store and picked up a remaned injector. I just read your reply, I will check those things before pulling it apart.
 
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KimsJeep

KimsJeep

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Ok, went out and did some testing with a test light and a screw driver. LOL Of course, it is running great today. No miss. I did put the screwdriver on it and I can hear it ticking as it should. I then tried putting the test light down the hole where the wire goes in. I couldn't get it to make contact that way. I think my test light is a bit to big to fit in the hole. I ended up unplugging it and putting the test light in the other end. It did come on in one of the holes. That is with the motor running. When I did that I also could hear a difference in the idle this time. Couldn't hear the difference yesterday. This just proves that it is intermittent.

So now I don't know if this is a PCM problem, a simple wiring problem, or an injector problem. I do know it has to something to do with the injector side of things and not the spark plug side of it though. LOL I guess the first thing to check is for any loose/broken wires going to that injector. May do that once it warms up a bit outside. :D
 
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Jerry Bransford

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Follow the fuel injector wiring toward the back of the engine and closely examine it where it bends around the vertical threaded stud at the rear of the valve cover. The stud's threads are known to wear through the wiring insulation causing wires to short together and cause intermittent problems.
 
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KimsJeep

KimsJeep

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Follow the fuel injector wiring toward the back of the engine and closely examine it where it bends around the vertical threaded stud at the rear of the valve cover. The stud's threads are known to wear through the wiring insulation causing wires to short together and cause intermittent problems.
Thanks, I will check it out. :D
 
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KimsJeep

KimsJeep

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Curiosity got the best of me. Went and did a quick visual and I can't see anything wrong. I will need to wait till to tear into it a bit more when I haven't been up all night working. LOL I took a few pics to share. :D

This one shows the big clump of wires incased in that plastic wire cover. All looks good on it.

3F7D8894-C1B3-4D75-8D8E-9E16706EAD58.jpeg


This next one is from the other side, I am thinking this is the bolt you mentioned @Jerry Bransford ? It all looks good there too.
29001D2F-375E-4580-9DF6-E332F9B9F6BD.jpeg


This last pic is of the plastic cover that protects all the wires. How do I get that apart?

032374BD-E96F-4486-BEC4-F12149865829.jpeg
 

Jerry Bransford

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This next one is from the other side, I am thinking this is the bolt you mentioned @Jerry Bransford ? It all looks good there too. View attachment 292334

This last pic is of the plastic cover that protects all the wires. How do I get that apart?
Cut the tape that is holding it together. Wrap it back together with black electrical tape once you're done.
 
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KimsJeep

KimsJeep

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Cut the tape that is holding it together. Wrap it back together with black electrical tape once you're done.
Yah, I'm going to cut the tape off the parts that are taped, but I need to figure out how to get the plastic bar looking thing that is in the last pic. Looking at the pic again, it looks like I can put a screwdriver in the hole and push that tab. I will give it a shot once I am more awake. LOL
 
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KimsJeep

KimsJeep

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Ok guys, hubby just put the new injector in. It doesn't sound like it is missing to me, but he thinks it is.

He put one of those light gauge thingys on the wire side of the plug and it lights when the Jeep is running. If you plug it into the injector you can here the injector doing it's thing when you put a screwdriver up to it and listen. Thing is, when you pull the plug off the injector, you can't hear a noticeable change in how it runs.

He is going to pull the plug out and do a compression check and also a leak down test. He said if that is the issue, we will just send the Jeep to a mechanic to have them redo the head and valves.

I will know more later tonight or tomorrow.
 
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KimsJeep

KimsJeep

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Hubby tried to do a compression check today, but he couldn't get his compression check tool thingie in the spark plug hole. It is has the ability to do both sizes of spark plugs and he couldn't get it down and screwed in. He tried to rig another one to work, but we don't think it is accurate. He used a compression checker that he had cut the hose off to use on something else at one time. It fit and screwed in, but then he had to use a gauge of one that you basically hold into the hole, it has a rubber end on it. He held it to the hole in the hose and managed to get a reading of 80 lbs of pressure on that cylinder. (#1)

He decided since we really don't know how will his rigged compression tool actually worked, and the fact that it was only 80lbs, that he will just take it to the mechanic he knows and have him do a compression check and get an accurate reading. If it is in fact bad, we will just pay him to pull the head and redo it.

So it looks like the Jeep may be down for the winter. I did tell hubby I want to do it asap, so I can get it back in time for spring. :D
 
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KimsJeep

KimsJeep

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Just letting you all know that I'm still around. LOL

Hubby found a better compression gauge and said it was getting 140 on that cylinder. He checked a different one and got 150.

We were supposed to drop it off at the mechanic on Tuesday, but hubby got mad because he wasn't open when hubby had time to give me a ride home. LOL Stupid I know, but hey, what can I do? LOL Anyway, I was going to try to find a ride but hubby said he will just take it to another shop that he deals with. So now we are supposed to drop it off next Tuesday. I did ask hubby if he knew what their hours were so he wouldn't be mad if they weren't open when he wanted to drop it off. LOL Sad part is, at the other location I could have walked home, it's not far from the house. It would probably take me about 15-20 mins to walk, 10 if I could jog. Problem is, we have been inundated with homeless and I don't want to have to walk by their RV's and garbage. Just don't feel safe walking, or running. LOL

I sure miss driving it. Hope they can figure it out.
 
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KimsJeep

KimsJeep

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Here's a video of the camps. For a few years it had only been about 4 the whole length of the road, but overnight, this happened.

They (city) are finally starting to clean up the homeless camp areas and are towing the vehicles for non registration. They do let them move if they can though and that is why I think this street got so bad overnight. They moved to the next location. There are other streets that connect with this one that have homeless on them too.

Hopefully the video works. LOL Just tried uploading it to youtube.

 
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Modoc Guy

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The homeless encampments are getting worse everywhere it seems.
I was going down 99 from Modesto to Sac the other day and saw a large camp near Gault I think. It was at a freeway on-ramp, basically on the freeway.

But what surprised me, was what was being done about it. They weren’t trying to get them to leave, it appeared the city or county had put a bunch of Waste Management style garage can on the shoulder of the freeway!

That might help with the garbage, but what about the human waste?

I’m wondering where all this is gonna lead to, because it can’t keep going on like it is.

I’m just sorry to hear you’re that close to the issue.
 
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KimsJeep

KimsJeep

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The homeless encampments are getting worse everywhere it seems.
I was going down 99 from Modesto to Sac the other day and saw a large camp near Gault I think. It was at a freeway on-ramp, basically on the freeway.

But what surprised me, was what was being done about it. They weren’t trying to get them to leave, it appeared the city or county had put a bunch of Waste Management style garage can on the shoulder of the freeway!

That might help with the garbage, but what about the human waste?

I’m wondering where all this is gonna lead to, because it can’t keep going on like it is.

I’m just sorry to hear you’re that close to the issue.
Yah, it sucks. I can walk out to my driveway and look down the street and see them. It's only one block from my house. I get to drive down that road everyday to go anywhere. The bad thing is, they come into the neighborhood to look for stuff they can take back and leave outside their RV's. They go through the garbage cans. One even cut my hose that I had out to water the lawn on the outside of my fence.

Yah, they (city) put a dumpster and porta potties down on Roseville Rd. (basically Auburn turns into Roseville Rd) and the homeless didn't use them. They did catch the porta pottie on fire once. LOL It's been a crazy 2 years that is for sure. Can't believe how many laws those people are allowed to break.

One thing I do find fun to do though, is when I am driving home and I have to make the left turn onto my street, I stay fairly close to the white line so the cars behind me either have to slow and stop or try to squeeze between me and the homeless RV. Yah, I am kinda hoping that one day someone will wipe out the RV, and if they hit my car, I will sue them and the city. LOL
 
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KimsJeep

KimsJeep

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We dropped the TJ off yesterday and told them all the stuff we already did to it.

Today I asked my hubby if he had heard anything and he said they called yesterday afternoon and said it was the distributor. He told them to go ahead and replace it as long as that fixes the problem.

We both thought that to be a little odd because you would think if it had a wobble in it as they say it does, it would cause more issues than just a misfire on cyl 1. Who knows though, maybe they are right? I guess we will see once I get it back, which I don't know when that will be. Hubby failed to ask that. LOL
 

aston4

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May 1, 2020
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Nm
How many miles on it again? I have 170k miles on one of my 4.0 motors and the distributor is still fine?