Jeep Hesitation / MISFIRE Resolved: Jeep YJ distributor

[@bradyrodgers1731]

I bought a '93 YJ with the 2.5L and it never ran right after warmup. Started easily and ran smooth when cold. After it warmed up for a few minutes, it would start missing and sputtering. I was convinced that it was something pcm or sensor related that came into play once it shifted from open loop to closed loop fuel injection. I started with spark plugs, wires, distributor cap and rotor. No change, still was missing after warmup. It didn't have a thermostat in it so I put the correct 195 degree thermostat, a new coolant temperature sensor and replaced the temperature gauge sending unit at the rear of the head since it was corroded and the gauge would fluctuate badly. No change to running condition. I replaced the coil since I was still convinced it was electrical in nature as the miss and sputtering was sudden, not gradual like starving for fuel. I also replaced the fuel filter even though the old one did not seem to be restricted at all. I put a fuel pressure gauge on the rail connection and it checked right to the book. 30-32psi at key on and at idle. Pressure would jump up to 40psi when removing the vacuum hose from the fuel pressure regulator and return to 32psi when put back in place. I replaced all the vacuum lines and connectors that looked in any way suspect. I replaced the crank position sensor and the throttle position sensor. I replaced the MAP sensor and checked the IAT sensor. None of these made any difference. As the weather got colder, it would run normally for a longer period of time but would still start sputtering and bring me to nearly a crawl after about 15 miles. The exhaust manifold was cracked badly so I removed the entire exhaust system and replaced with a four tube header and downpipe, new muffler, deleted the CAT and new tailpipe. While I had all this off, I scrubbed the intake manifold and throttle body clean, inside and out. Removed all the fuel injectors to clean and replace all the injector o-rings and cleaned the ports on the intake manifold and fuel rail. Put it all back together with a new Felpro gasket. It still made no change. The voltage was erratic from the old alternator, even after cleaning all the ground connections so I replaced the alternator. The timing chain was very noisy and I suspected that the cam timing may have jumped a tooth or two since manifold vacuum at idle was 18 inches. The cam chain tensioner had come apart so I put a timing chain kit in it. No change to sputtering condition. I replaced the distributor with a new one, thinking that perhaps it was the cam position sensor. It was really corroded and the distributor gear was very badly worn so I was glad to have replaced it. Again, it did not help. I replaced the pcm with an ecm out of a '95 model that I knew was good. I did look at the internals on my pcm and the capacitors were not discolored or look to have ever been disturbed. No change. I finally hooked up a long air line with some connections to the fuel rail and passing through a firewall bushing to my fuel pressure gauge in the cab so that I could observe the fuel pressure as I was driving. Sure enough, at the point where it started missing, the fuel pressure was dropping to 0-5psi for a few seconds. What was happening was that as the fuel pump warmed up, it would start failing. As the weather got colder, and the gas in the tank was colder, it would take the fuel pump longer to get warm and start failing, So even though I checked the fuel pressure early on with a gauge, and it checked good to the book specs, it would nearly fully fail after it warmed up good. Replaced the fuel pump and it has been running like a top. Actually, with everything new, it probably runs better than it did when new. I get over 18 mpg with it (5 speed on 33x12.50x15 tires). So you never know with these things....even though something checks good, doesn't mean that it is always good.

[@JeepSolid]

Dang! What a hassle. Sometimes the hardest part is finding the issue. Good job

[@jamesdodson9417]

Gee wiz man at least you taught a few of us what to look out for and seems like your Jeep won’t stand you cause everything is new and the piece of mind she is solid . God bless man .

[@moabwheeling1305]

Congratulations Dale , I'm glad you have it running great . Looking forward to your next video my friend . Take care and catch you on your next video .

[@loco0351]

Having the same issue but also needed to change the timing chain. 98 grand Cherokee with 341742 thousand miles. Timing chain done last night now waiting for distributor to arrive.

[@johnwagner8465]

Thanks for the video..towards the end I was like ..ahhh he didn't fix it..but you did..awesome

[@robertfitzkee3862]

So where was your distributor pointed to when you finally figured out was it at the 5:00 or 530 where was it said at when you figured I'm having the same issues

[@Davidshomeworkshop]

Congrats! Nothing better than fixing a problem.

[@JeepSolid]

Thank you!

[@roccom5988]

Brilliant job my friend. Enjoy the weekend. Greets from Belgium.

[@JeepSolid]

Thank you! Will do

[@davidcrowson4745]

Always enjoy your videos 👍

[@JeepSolid]

Thanks for following along!

[@petermurray898]

I'm having the same problem as you, checked all things you checked, decided on a new distributor, but now I'm having the same problem you had when replacing the old one. But you didn't go through what you did to get it to run properly???

[@projectbumblejeep4190]

It wasn't until the early 2000's that most vehicles were not meant to run on fuels with ethanol additives. I believe your problem is the fuel you run, not any sensor related problem. I went through the same problem with my 94 Cherokee. I replaced ALL the sensors plus all of the ignition system, and still had the same problem. Now to qualify my problem, I only filled my tank every 4-6 weeks. I've only put 16k miles in the last 4 years. It took about 5 tank fill ups to get all of the ethanol fuel out of my tank (5 months). Once I was running non ethanol all of the time, my problem went away. If you are letting an older vehicle sit for long periods of time, I would stick to non ethanol fuel. Ethanol is hydroscopic. Simply put it draws water to itself. The water in your fuel is the most likely thing causing your problem. Hope this helps. God bless and stay well.

[@Hillbillypunk]

Are the distributors in a fixed position on these? In my experience, which is absolutely zero with Jeeps (just got my first YJ) you get it to tdc on #1, and just drop the distributor in, wherever it's now pointing, is now the #1 plug wire. But those were adjustable.

[@danlewandoski8092]

Hey There, so mine has some hesitation here and there and you mentioned it was the Cam sensor. I’m having trouble verifying mine even has one. I didn’t pull off the cap yet. Definitely has the crank sensor but it’s not in the distributor cap. You said yours was. Is yours a 4.0 or 2.5? Mine is the 2.5 Thanks for any help.

[@dentondunn4346]

My 95 YJ 2.5 has a hesitation until about 2 grand and then picks up well but under load or when I’m flooring it I’m getting a misfire and I’ve changed plugs, wires, throttle body positioning sensor and still having the same issue. Check engine light is on as well but what could possibly be the culprit? Cap and button, 02 sensor or what? Someone please help me cause it’s my 1st wrangler and I love it but rather fix it than trade it off for something I don’t want as much as the wrangler

[@SimplyMustGo]

My Jeep was doing something like that though it wasn’t so much a hesitation as a violent shaking at a certain RPM. Turns out it was caused by the distributor being shot, the teeth were shaved down to almost razors, and spark plugs. I’d put in nice one, but turns out the YJ just prefer the copper ones.

[@JeepSolid]

Dang! Did you notice any Metal shavings in your oil?

[@SimplyMustGo]

@@JeepSolid I didn’t, but mostly because we replaced the engine but had used the old distributor still, so when it ran poorly one of the first things we replaced was the distributor, so it didn’t have much time. The spark plugs though took another couple of days to figure out.

[@IankoLeite]

Have been waiting this video for so long!!! Thanks for not forgetting to show the solution for it.

[@JeepSolid]

You’re welcome! So happy it’s fixed now

[@maetb]

I was wondering about this the other day too :-)

[@mattryan2291]

I have a '90 YJ 4.2L with a Mopar fuel injector system ( which describes itself at a '94/'95 when ordering parts). I'm getting a really rough idle on warm re-start. I installed new injectors and heat shield on fuel rail and lines thinking it was vapor lock. Still having the same problem. New fuel pump as well. Any ideas?

[@GlenFerrisMusic]

Great vid but on my YJ 2.5 4 cylinder 1988 I have undone the retaining nut but the distributor base won't budge at all so I can't move my rotor to the 1 mark when she's at TDC. Yours just seemed to lift out with two fingers, I can't even leverage mine out with screw driver. Any advice Dale?

[@bob4003]

HEI distributor ??

[@thesetruths1404]

Hi I have a 2007 Liberty 3.7L V6, 117,000 miles. Owned it since 67,000 miles. It operated perfectly for the first 30,000 miles and then it started getting a #1 Cyl misfire code P0301. It also seldomly gets a #1 cyl fuel injector circuit open P0201. It must be a very mild fault as the misfire freeze frame data shows it always happens at less than 350 rpm and when cleared it comes back immediately at next startup, cold or hot. So it seems to only happen once on startup as its moving up to regular idle speed. The miss isnt noticeable when driving or idling. Its getting 15.5 mpg fuel mileage. Doesnt burn oil. Doesnt smoke. Has great power. I've changed plugs and coils but no difference. Cleaned air intake, air filter, and ran cleaner through system. I've cleaned and inspected the injector plug and all wires but no difference. Dry / wet compression test of #1, 3 and 5 cylinders all read good: 160 / 175 psi. I'm wondering if there's a mild wire defect for that injector, or just a flakey connection somewhere. Has anyone tried to use a new set of compatible gauge wires and run them to a place closer to the injector control? I can't see where the wires go though. I'm not sure if I should just live with this, or troubleshoot it more. I don’t care about the engine light as we don't have emission requirements. Now that I know the compression is good, I'm not so worried about it. Any suggestions of what to do next? Thanks!

[@serf3469]

my 1999 TJ sounds like a similar issue, when I start it up, it seems hung over, I start it in the morning and it sounds like it almost wants to die, then stays on, the rpms are wacky, they get high, when I put it in gear, it will go without me putting my foot on the gas, when put my foot on the gas, it almost wants to stall, and when I push down on the gas, it takes off. when I go about 40 to 50 mph it hesitates. when I put it in park, the rpms go up to 1500 2000 and bounch around, sometimes it goes lower but I turn it off when it is high, also it seems hot underneath, so this video seems like the culprit but then so does the video for catylitic converter. Not sue which option. I had the IOC replaced, the oxygen sensors, spark plugs are looking good but this cam sensor could be it, any suggestions between cam or catylitic, which does it sound to you, because every choice for me has been a garage bill, plus no engine lights go on, the last 3 mechanics had no engine lights to work with and they are all stumped as they just replace something and after a day or two same issues.

[@jamesdodson9417]

I had a 85 mustang when I was a kid my car would just shut off randomly , that was a heck of a grimmlin to find , it was the igniter in the distributor it only took about less than a minute to cool and the car ran fine , how I figured it out I noticed when it died and tried to restart it the tach wouldn’t jump “ no spark” but let it set for 30seconds and bam turn the key see the the tach jump and it would fire up . I know not all tachs do that but it’s all a learning experience, thanks for your hard work and wisdom God bless you and your family.

[@ryanhayward5910]

Dale I’m having a similar problem but in my case it only happens when it rains and wet out. Jeep doesn’t like it when it rains lol. Any ideas? I’m thinking it’s a short somewhere. Plugs and wires and cap were replaced last summer. Any ideas?

[@leonard-pr3887]

I have a problem with my wrangler 93 cracks all coils i replace what any recomendations??

[@clintclendaniel3752]

I have a 98 dodge Dakota with the 2.5 4 cylinder motor got the hesitation at any rpm stop or driving please help me

[@luthawbawtho3485]

Can you tell me how to fix 1993 jeep yj 4.0 auto shutdown problem ?

[@shoukatm436gmail.commehran7]

Jeep land cruiser 94 fault on driving top grear speed reduce and get stop while shifting grear and also heat gauge slightly up .any idea ?

[@spymaine89]

idle air

[@irishguy8208]

Dale: Isn't this the Jeep Wrangler that you rebuilt the engine on? It was not that long ago if I am correct. Why the heck are you having so many problems with a (New) build??

[@JeepSolid]

Engine build is great. No issues. Runs super smooth. In this video, I have a sensor issue

[@projectbumblejeep4190]

You might also check your coil for cracks. Spark leakage will also cause this type of problem.

[@dealinwithit1]

Love your channel, I’m building a 93 XJ 4.0 , I’m also having trouble installing a new Distributor, so did you just keep playing with it til you got it right?

[@JeepSolid]

Yeah. I had to just keep messing with it until I got it right. Kinda a pain, but maybe I’m just not gifted at that job. LOL😂

[@-_-John-_-]

✅

[@jimhansen3752]

What was the position of the rotor at TDC when you finally got everything lined up correctly?

[@JeepSolid]

Just past the #1 plug wire

[@jimhansen3752]

@@JeepSolid Your comments about not needing to worry about the alignment of the oil pump slot was a game changer. I'm pulling my distro today to see if I feel into that trap and settled for a sub-optimal timing setup.

[@robertperrin4070]

Dale, you rock! I changed my distributor a few months ago on the 2.5 and had a fun time getting it sorted. Did yours include a gasket?

[@JeepSolid]

No. Didn’t include a gasket

[@bigbang7897]

So are you saying it wasn't the old Distributor or the timing but just the cam position sensor and can I ask why you didn't install the distributor as you did in your previous videos ie TDC No1 cylinder, set oil pump at 11 o'clock, set hold down bracket to about 1 o'clock and slot in the distributor.

[@JeepSolid]

Yep. Turned out to be the cam sensor on the distributor. Tried to set tdc piston 1 and line up rotor to #1 cyl, but was just off a bit. But got it up and running after fiddling with it a bit. 👍🏼

[@bigbang7897]

@@JeepSolid I have the same problem with my ZJ when I do the set up as per the book but my rotor arm is not in line with the pickup on the cap for No1 cylinder have you any fix or way around it the misfire is driving me mad.

[@litz13]

The call of the camshaft position sensor in the distributor causing your hesitation is dead on the money. Had the same thing happen on my 97 XJ. And yes, the whole distributor isn't much more than the sensor by itself.

[@JeepSolid]

Hardest part was narrowing down the issue.

[@litz13]

@@JeepSolid it's a good bit easier on the newer ones where you have ODB to help. It has data pids where you can see pulse and sync status between the CPS and CSPS.

[@scottb6194]

Dale, use a silver sharpie and number the distributor cap like the wires.

[@JeepSolid]

Good idea. I am a labor fanatic. Haha

[@careleentoh3487]

とうございます」、

[@jeanclauderoget3756]

Nicely done, the process of elimination works every time.

[@JeepSolid]

Yeah. Finally got it.

[@Tony-hg9kc]

Wow man that jeep turned out really nice

[@JeepSolid]

Thank you!

[@badassYJ69]

I am having same issue with my 93 YJ Sahara after replacing the distributor, so maybe I have it one tooth off.... I will pull it back out and back off the rotor one slot and see if that solves my issue. It ran fine before, I had to replace the distributor because the bushings went bad and it was making a lot of noise.