Jeep Wrangler Forum banner

ready for a challenge? help me diagnose my awful running jeep

5K views 90 replies 12 participants last post by  wrscpc07 
#1 ·
I've been so frustrated with this I am ready to ask for help from you guys. My 97 2.5 wrangler has been running like crap for about a year. When I start the jeep, which sometimes it stalls right after I start it, the RPMs will basically drop to zero (if it doesnt stall) and be so quiet you wouldnt even know it was running. I have to continue to give it gas which results in backfiring. Then, I can get it moving. It will backfire while driving and there are dead spots while accelerating where the jeep has absolutely no power (scary on the highway). 2 months ago my CEL came on for my crank sensor, changed that. However yesterday it acted up again, CEL light, crank sensor again. Changed it. No more light. After i put the sensor in, and the last one, it will run like absolute :censored: while it seems the computer recognizes the sensor, all backfire and can hardly make it down a side street. Then it will run a little better than it did when the light first came on but it still loses power, backfires. Sometimes it will have a burst of acceleration, typically after I get it going at a red light. Mostly in 1st and 2nd gear it will really have a hard time going. And the problem seems to be a little better after the jeep gets warm.

What i've done in the last year:
new crank sensor
new plugs and wires
both my up and downstreat o2 sensors have been replaced
new muffler and tailpipe
new tps sensor
fuel pump was done 3 years ago

I currently have no CEL but the jeep is starting to become dangerous pulling out in traffic. What ive read on here people have been saying maybe the MAP sensor or ICM. I am going to replace my distributor cap today.

anyone else solve this? Thanks im desperate here with this one
 
See less See more
#2 ·
reading more and more threads. Found a few that say to change the ignition coil. So maybe before the MAP sensor ill do the cap and new ignition coil. I guess i know where to look im just trying to see if anyone else has actually solved this before replacing every sensor..driving me nuts!
 
#4 ·
From reading ive found out my 97 doesnt have a cam sensor..they didnt put those in until 2000..correct me if im wrong. ive done the other sensors and plugs so i think ignition coil will be the first thing i try next..seems to be the culprit for a lot of people
 
#7 ·
The 1997 Mopar parts catalog shows a "switchplate, distributor" p/n 517603AA for the '97 2.5L engine. That part has a different appearance than the camshaft position sensor used in the '97 4.0L but Mopar's parts catalog calls them both a "switchplate, distributor". It is also located inside the distributor housing.

The below ignition description doesn't differentiate between the '97 2.5L and 4.0L engines when it describes the use of the camshaft position sensor.

This is what the '97 FSM says...

"CAMSHAFT POSITION SENSOR
The camshaft position sensor is located in the distributor
on all engines (Fig. 2).
The sensor contains a hall effect device called a
sync signal generator to generate a fuel sync signal.
This sync signal generator detects a rotating pulse
ring (shutter) on the distributor shaft. The pulse ring
rotates 180 degrees through the sync signal generator.
Its signal is used in conjunction with the crankshaft
position sensor to differentiate between fuel
injection and spark events. It is also used to synchronize
the fuel injectors with their respective cylinders."
 
#8 ·
The 1997 Mopar parts catalog shows a "switchplate, distributor" p/n 517603AA for the '97 2.5L engine. That part has a different appearance than the camshaft position sensor used in the '97 4.0L but Mopar's parts catalog calls them both a "switchplate, distributor". It is also located inside the distributor housing.

The below ignition description doesn't differentiate between the '97 2.5L and 4.0L engines when it describes the use of the camshaft position sensor.

This is what the '97 FSM says...

"CAMSHAFT POSITION SENSOR
The camshaft position sensor is located in the distributor
on all engines (Fig. 2).
The sensor contains a hall effect device called a
sync signal generator to generate a fuel sync signal.
This sync signal generator detects a rotating pulse
ring (shutter) on the distributor shaft. The pulse ring
rotates 180 degrees through the sync signal generator.
Its signal is used in conjunction with the crankshaft
position sensor to differentiate between fuel
injection and spark events. It is also used to synchronize
the fuel injectors with their respective cylinders."
Ah ok. Now I'm not sure to do the ignition coil or the "switchplate, distributor". I see it works with the crankshaft position sensor which i have replaced twice already..so maybe I should start with that sensor first then if all fails do the ignition coil
 
#9 ·
i decided i would do the camshaft position sensor..but for the last 20 minutes i cant find the damn thing on any website. autozone, rockauto, etc. The only CPS that exists is the crankshaft which ive already replaced..if this sensor exists why is it not available? Do I have to buy the whole distributor? Autozone says my jeep only has the crankshaft according to their system
 
#11 · (Edited)
If they can't find it, they're not looking for the right part name... it's not called a camshaft position sensor in the Mopar documentation either.

I tried to upload a .pdf showing that page in the Mopar parts catalog but there's something unusual going on, it won't display after I upload its .pdf... but it looks like you found what you needed.

Edit: Just download the cps.pdf, you can view it after you download it.
 

Attachments

#12 ·
If they can't find it, they're not looking for the right part name... it's not called a camshaft position sensor in the Mopar documentation either.

I tried to upload a .pdf showing that page in the Mopar parts catalog but there's something unusual going on, it won't display after I upload its .pdf... but it looks like you found what you needed.

Edit: Just download the cps.pdf, you can view it after you download it.
I found from another thread, that you also had commented in about not being able to find the sensor. They call it the "pick up" which i have no idea how youre supposed to find..thank god for this forum
 
#13 ·
Make sure you are very careful when replacing the CAM sensor. It can be very tricky, its not just plug n play. It has to be in the same position as the previous sensor, make sure you watch some videos before hand! I had to tray a few different times to get it right.
 
#14 ·
Also, since you are suffering through so many different symptoms, it could be due to several problems rather than one.

Have you removed your throttle body and IAC and cleaned them very carefully? (If your 1997 2.5L does not use these parts then please forgive my ignorance!)

The IAC - idle air control - motor it a little plunger that fits into a hole in the side of your throttle body. When you let off the pedal the throttle closes and could snuff out the engine. So the IAC opens to allow a predetermined amount of air through so you idle properly.

The throttle body gets varnished up all over and becomes sticky, sometimes not closing fully, sometimes sticking a bit. It is good to remove it (four bolts, uses a paper gasket that if you are very carful you can re-use, no sealant). Disconnect the sensors on it. (There are three on the 4.0L. Or is it four? Hmm...) Spray it down with the right cleaner and go after it with an old tooth brush until it is sparkling. There is a small hole/port that must also be cleaned, that goes to the IAC. Then you need to carefully clean the IAC housing on the throttle body as it is sort of intricate.

Clean the IAC *very* carefully. Watch videos. Read up on it. Once you have it moving freely and the head and its receiver on the throttle body are super clean, reinstall all that stuff. If the IAC acts up your idle can be all screwed up. If it sticks in the extended mode it can just about cut off your engine unless you give it gas with the pedal. If stuck in the open (retracted) position it can run at higher than normal RPMs at idle.

No way to know if these things being dirty are contributing to your problems, but I would clean up these parts anyway, as it is very good to learn how to do this. It needs to be kept up with it from time to time, too.

It might do nothing right now. It might make things better. It might solve serious problems down the road. Again, good to know how to do.

The IAC is the only sensor on the throttle body itself that is serviceable. The others have to be replaced. However, you can trash the IAC if you are not careful, and it is not exactly cheap to replace, so be careful!

Good luck!
 
#15 ·
I have cleaned the throttle body with cleaner and I have also taken each sensor off of it and made sure they werent dirty or nothing clogged them. And I put a new gasket in while I was at it. This problem started to happen maybe a year later but ill do another quick cleaning of it. Dfinitely wont hurt!
 
#16 ·
So I replaced the cam sensor in the distributor. I noticed right away my idle was way more on point. It didn't jump and it stayed between zero and 1. It jumped like crazy before. I took it for a quick drive..but some backfiring was still there. It was a little better going from a complete stop from first to second, it didn't quite hesitate as much. And, i was actually able to pick up better speed without it hesitiating on me when I floored it. But you could still feel a problem. I did notice while putting the sensor it that the bottom of my distributor cap had some corrosion, so i went back to the store, put a new cap in. I just took it for a few miles and it definitely feels MUCH better. I got a litte hesitation backing at of my driveway and the stop sign down the street..but after that, no backfiring at WOT and I was definitely able to feel more power (the little that the 2.5 has lol). But it was definitey more sluggish before the new cap and cam sensor. After a mile or so, it seemed that from a dead stop into first then second there wasn't hesitation. The problem seems to be gone..or if not, it is definitely not as obvious. I'll see how it is after a full day of driving it. SOmetimes things feel fixed for a few miles then act up again..ill be sure to comment on how it is in a day or so.

thanks for all the help
 
#23 ·
actually, thats when I cleaned my throttle body because I took it off to put the 4.0 on, and it ran pretty bad..i reused my same sensors but it ran pretty bad. I thought it would be a quick swap but it didn't work out so i took it off, put my sensors back on my original one and cleaned it up and put it back on with a new gasket. I dont know why it acted up with the 4.0 when several other people have done it
 
#24 ·
sooo when I thought it was fixed..it's not. It took me about a minute and a half of reving up to even get out of my driveway. And on top of that, my power steering started to leak:atomic: not sure where to even go next with this.
 
#26 ·
I've already replaced my fuel pump. And when my original one went on me..I had none of these symptoms, it just died on me while driving. And i doubt a pump will fail for a year without failing completely. Maybe I should have done mew plugs even though i did this spring. Or a new rotor, which i havent done in a few years
 
#27 ·
I read another thread with this same issue and his was a leak in a fuel injector due to a faulty o ring, but i sprayed starter fluid on them and no change in idle, so im assuming I don't have a leak there. But man, it sounds like multiple shot guns going off when i rev that thing to move out of my driveway
 
#29 ·
im going to pick up a rotor. ill look and see how my plugs are, i just put them in right before summer. Id rather pick up an ignition coil before i replace plugs again
 
#33 ·
Well my jeep died on me at 230 a.m in the McDonald's line. Had to get out and push it. I was running low on fuel, but I was 2 miles from home and I've never ran out of gas but that's what I thought It was. Called AAA, got gas and no go. Wouldn't turn over. Weird, my battery read absolutely zero, didn't move when I turned my key but all my radio and lights worked. Got it towed home, and now I have to figure all this out. Any suggestions where to start? It just died, hesitated a tiny and died. I will investigate.
 
#37 ·
ha, I got in the jeep this morning to try and start it and bam, fired up. It died in a second or two but the second time i started it it stayed running. But of course now im scared to take it anywhere and have it die on me. All my sensors are tight, plugged in..i dont know where to go
 
#41 ·
They stay on. There's no signs of a dead battery or anything. All lights and radio remain work in while the battery gauge reads nothing. I read that the crank sensor will cause off gauge readings but I just installed a new one..maybe I'll take it off and make sure it's clean and sitting perfectly
 
#42 ·
In July my check engine light came on for the crank sensor. No big deal, changed it and all was good till about a week ago when it went off again for it. Put a new one in, had no shutting off issues and now this. I wonder if it's defective. Is this one of those sensors I should get through the dealer?..
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top