Jeep YJ-Series

1998 Jeep YJ-Series Drive Train / Driveline   

1998 jeep cherokee sport. 4.0 ltr,aw 4 transmission. My jeep will not downshift on its own. Downshifting manually works fine. Changed neutral safety switch and transmission control unit. Could it be, or is there, the fuse or resistor that feeds the t.c.u? where are they located?

Hello,

Is the check engine light or other warning light coming on?

Does the engine stall if you don't downshift manually after reaching higher gears?

my jeep upshifts fine. engine does not stall ever. occasional check engine light. just read codes they were po700 p1281 p1698 po 123 po442 po445. cleared them out test drove and re read codes w/ no codes after test drive but still doesnt want to downshift automatically.

You may have to test a drive a little farther to get codes to appear.

There should be a TCM fuse amongst the underhood fuses.

Check for connector or pin damage (corrosion, push-outs, etc) at the TCM and transmission.

Is the trans staying in High or Second gear?

it stays in high gear until you pull it down to low then u can put it back to drive and it works fine til u stop again

i test drove quite a bit further today. i took it out pulled some pretty good hills. It will downshift from 4th to 3rd ( such as passing gear ) with it in od. If i put it in 3rd and give it throttle it will shift down once again. Still confused. There is no t.c.m. fuse under hood. Any more suggestions?

1995 Jeep YJ-Series Engine  When driving When warm 

while driving above 60mph the check engine light comes on after a few minutes and stays on till i turn the truck off. i've been told it might be an O2 sensor but i can't find a diagram of where the O2 sensors are so i can't troubleshoot them. maybe you guys have an idea.

Use the following link to access a free online repair guide for your Jeep. Once you access the guide look under 'Emissions' for instructions on self diagnostics. These instructions will allow you to access trouble codes in the vehicles computer (PCM. Let me know which trouble codes you find.

While O2 sensor failure is common with age, never replace a sensor in hopes of turning off a check engine light. There are to many things that can turn on the check engine to just concentrate on one, over time this would lead to unnecessary repairs.

http://autozone.com/servlet/UiBroker?UseCase=RG001&UserAction=viewRepairGuideYMMEYear

1995 Jeep YJ-Series Engine   

I have a 1995 wrangler that takes for ever to start when the temp drops below 70 degrees. It turns over but will not start. I hold the key for sometimes 5-8 minutes and then will try to fire but stalls after that it will usually start right up. During days above 70 degrees it starts with no problem. I have had the fuel pump and filter replaced last week and still acting up. Also before it fire up the check engine light starts to come on and off then it starts up. I have checked but no codes. Any help would be great.

Do a fuel press test when starting. Dirty injectors may cause the fuel press to bleed off.

I will try that in the morning but dont understand the temp issue. Why it will start right up when it is warm outside. I forgot to mention this is a 4.0 6cyl if that would make a difference

There are coolant temp sensors and air intake sensors in the Jeep.Even though
there are no codes there still might be
a sensor problem.

That is my problem I have had this jeep to two different shops and they cant figure it out. I dont want to start replacing every sensor on my jeep till the correct one presents itself. This is why I am on here. I need some ideas, things to try before I have to spend a fortune. Thanks

If you had it scanned with a decent csanner(like a Snap On one)then you might have to replacea sensor or two. I do not know what scanners your shop uses, but some economy scanners miss some codes. Some auto parts places offer free scans, so you might give them atry.

1994 Jeep YJ-Series Ignition System Won't Start  

My 2.5L won't start (fuel pressure seems fine). I'm not getting any spark to the distributor. I replaced the cap and rotor, and removed the ignition coil, bench tested it, and it was fine. All the cables and plugs are relatively new (2 yrs) and in good shape. I have been told that it could be the on-board computer, or something about a rollover sensor that has gone bad (I don't know if there is a rollover sensor in a '94). Any suggestions would be very helpful.

Hello, Do you have voltage to the ignition coil?

I'll look up wiring diagrams and see what to suggest.

Roger

Do you have a fax number? I'd like to send you three pages of troubleshooting procedures for "Failure To Start".

Please advise,

Roger

Hello, Would you like to move forward? I have some info I'd like to fax for your review.

Thanks,

Roger

Please update the status of your question.

May I fax some info to you? Where?

Roger

1994 Jeep YJ-Series All Part Groups   

when i turn my ignition on i get a clicking sound from my fuel pump relay i just changed it and it didnt do anything. the colder it is the longer it will click for then the clicking slows and the check engine light comes on and i can start it. if it is under 30 degrees it just keeps clicking fast.

Hello, I'm seeing this all to often of late.

The PCM supplies ground to the Auto Shutdown Relay and the Fuel Pump Relay at the same time the instant the key is turned on when all is well.

Some owners report that the key must be left on for up to thirty minutes before the relays will energize and allow the engine to start. Then the relays click rapidly and the engine will start. Once it starts it is as though the Jeep didn't have a problem at all.

The relays should energize and remain that way until the key is switched off.

My work along these lines points to blaming the PCM for not providing a constant ground to the relays.

What engine do you have and what series YJ is your Jeep please? I'll get a wiring diagram and even send it to you if you provide your email address.

Roger

its a 4cyl i think its an s not sure just the regular

I'll get a wiring diagram and even send it to you if you provide your email address.

Roger

[redacted]

Thank you for the address. I'll scan the drawings to email for you and send them along.

Roger

not really sure what a pcm is, always say there is no computer under i think 97 can i fix it or rig it or do i have to find a new one

A PCM is a power train control module. Look for it under the drivers side of the dash panel. Your Jeep has this computer. Look on the wiring diagrams I sent you. There are many circuits in and out of the PCM.

Did you locate it?

Roger

1994 Jeep YJ-Series Engine   

I have a 1994 Jeep Wrangler Yj, 4 cylinder, manual transmission. I need a new PCM. The model number of the current PCM is 56028289. I found a possible used part but the part number is different 56027574. Will the used part be compatible with my vehicle?

First of all, how has it been determined that you need a new PCM? This is very difficult to determine (and factory diagnostic trees can erroneously point to PCM failure).

Computer diagnostics run 2x at a local Midas shop. Engine turns over but does not "catch"; it was determined via the diagnostics that no fuel is being released and there is no spark.
I had the Jeep in the shop yesterday for a timing assembly replacement and catalytic converter/exhaust replacement. It used to start just fine before this work

Did the problem happen while it was in their possesion? If they did any welding on the vehicle, this can damage the computer. Much more likely if safety precautions are not taken (disconnecting the battery).

Genesis scanner used with diagnostic tree to determine the issue.
No welding was done in any of the repairs.
When I picked up the vehicle yesterday, it wouldn't start immediately, but after about 6-7 tries it finally fired up. It then ran fine for the rest of the evening (stopped and started a couple of times with no problem). This morning, trying to start it after it had been sitting overnight, no go. The starter sounds fine, all of the spark wires are on snugly.

How much is the replacement computer?

Midas was going to order one from the dealer for $453 (no after-market available locally) but I found a used one (grade A) at Webster's in Connecticut for $125 (+ shipping)
I gave Webster's all of my info and the part is supposed to be for a '94 Wrangler S Yj 4-cylinder manual transmission.
I understand parts numbers can change over the years but I wanted to have some assurance of compatibility before spending the time and money

The stock number at Webster's is e1[redacted] 4 which almost makes me think it is from a 1988 Wrangler (especially since the model number is smaller than the one on the '94)
Just a little extra info

Woodville Auto Parts (Ohio) [redacted] , is the only listing I can find with a matching number for your computer.

I was very surprised at how hard these are to find.

Hollander lists the computers as interchangeable, although it does not appear an '88 and '94 are interchangeable. Hollander is really all there is to go by, but I would still ask the reseller to guarantee the application (see how much faith they have in the interchange system, as they have a lot of experience with them).

You may also wish to search Ebay. Contact 'jeep_part_source', they did not have a computer listed for your application, but may have one that is not currently on auction (might be hard to sell and not worth the listing fees).

rockauto.com lists computers for your vehicle, although the part number does not match exactly.

partsamerica.com (Advance Auto) also lists your computer, with a matching part number. Not cheap though.

By the way, when the engine did start after the repairs, did it run fine (just as it did before the "repairs")?

Once we got it started it ran great.
I'm guessing this is just a suspicious coincidence, but I don't feel like the mechanics at Midas are gouging me.
I really appreciate all of your help; I will check out the sites you recommended.
Thanks!

1994 Jeep YJ-Series Electrical / Lighting Systems   

Low beams do not work.

Hi, Do you have a wiring diagram? Have you removed a headlamp and tested for voltage at the wiring connector?

Roger

1993 Jeep YJ-Series Electrical / Lighting Systems Malfunction Happens always Always

No parking, dash panel lights. Headlamps and brake light do work. Dash board swtich is good and so are fuses.

Hello, Do you have voltage output from the headlamp switch on the BLU/RED wire when the switch is in the Park position?

Please advise,

Roger

I do not have a red and blue wire. However, I did find a hole in the switch when I pulled it from the dash. My turn sidnals and hazards work as well. Do you think it could be the switch? I did have voltage from all the connections going into the light switch.

The data base lists Cherokee, Wrangler, etc but does not list the YJ.

I can again access the wiring diagram to clarify. What model do you have please?

Roger

It is a 1993 Jeep Wrangler Sahara with a 4.0 ltr 5spd. 4wd

I looked again at the data base from Chilton.

What color wires does your headlight switch have? Are there five wires?

Roger

Yes ther are 5 wires. They are blk/yel, grn/wht, red/orng, grn and pinkish

Chilton must be color blind. I'll check the Mitchell 1 Data Base tomorrow.

Meanwhile, there should be power coming into the headlamp switch on three of the wires.

The remaining two wires should power up when you turn on the headlights. One goes to the headlight dimmer switch and the other goes to the park light circuit.

If you select only the park lights only one of the wires will power up.

Does this happen for you?

Roger

OK, I have a wiring diagram from the Mitchell 1 data base. The colors match your description.

If you would like a copy please provide me the email address or fax number where you can receive the information.

The BLK/YEL is the wire that is switched hot to power the park lamps. This wire also powers the illumination lights dimmer control.

When your headlight switch is on do you have power outout on the BLK/YEL?

Roger

yes please send me a copy.

The black and yellow wire has no power at all. Evry other wire will give power. When I have both the parking and headlights on, all but the black and yellow wire give power.

That's the problem. The switch does not output poer to the park lights and to the dash lights via the dimmer control. I believe the headlight switch or the connections to it are bad.

If you would like a copy please provide me the email address or fax number where you can receive the information.

All Parts has your email information but I do not.

Roger

[redacted]

how difficult would it be to change the connections if they are bad? Could I just change te black and yellow wire if it is the only bad one?

Inspect the connections at the headlight switch. Are any burned? Deformed by heat?

You stated there is no power output on the headlight switch terminal for the BLK/YEL wire. Do you believe this is because of a bad connection or a bad switch? If the wires and connection terminals look all right then replace the switch.

If the BLK/YEL wire has a bad connection you can replace it only as you had hoped.

I'll get that diagram to you.

Roger

How are you doing here, please? I could use an update.

Any news?

Roger

Got it figured out. The switch was bad. Thanx for your help

Great! To accept my answer so that All Parts will pay me please click on the OK TO PAY MECHANIC button.

Best wishes,

Roger

I cannot find the OK to pay mechanic button. Can you tell me where it is?

Sometimes this happens...

Will you instead email All-Parts.com, Administrator, All-Parts.com and tell him you would like to accept my answer so that I may be paid?

I do not get to "see" your screen text so I am not certain how it reads. Mark will take care of it.

Thank you! Happy Thanksgiving,

Roger

1993 Jeep YJ-Series Engine   

1993 jeep wrangler with i6 4.0. started having a rough idle with extra lifter noise. pulled the valve cover off and ran the engine and found one of the lifters to be squirting oil into the air instead of a nice flow like the rest. all lifters, pushrods and rocker arms were replaced less than a year ago to reduce noise. could this lifter be locked but why does it pump oil like this and could it free up. I'm just about to replace the motor do to the milage 115k and not wanting to pull the head again just for lifter change. thanks

The clearances inside an engine are not always 100% perfect. It is possible to get lifter bores that are not the same size.
The lifter that is squirting oil is not unusual, the ones that are not are possibly restricted.It is actually not the lifter, but the lifter transmitting oil through the pushrod, and then through a small orfice in the rocker arm.That in turn oils the rocker arm pivot and the rocker tip that pushes against the valve stem tip.If the rockers appear tight, you may want to inspect the underside of each for unusual wear.Also determine the pushrods are straight (roll on pce of glass) If you replaced the lifters, it might have been a temporary solution as the camshaft lobes are also prone to wear also. If the engine otherwise runs ok, you may want to consider a cam change.If you are convinced that an engine swap is imminent, try running an oil engine flush (hot) and switch to 15/40 oil. Assuming the oil pressure is ok also.

1993 Jeep YJ-Series Fuel System   

removal of fuel tank.

I have a 93 and have been attempting to remove the fuel tank and it wont drop. Can you please walk me through the necessary steps to remove and replace the fuel tank?

Assuming that you removed the straps/mounting hardware, did
you disconnect the fill hose?
Sometimes tanks can get a little sticky as they have a sound deadener on top. Usually gently prying down works, When partially down, then disconnect the fuel lines and wiring.Hope its not full of gas!

1993 Jeep YJ-Series Electrical / Lighting Systems   

Bought a new solenoid for starter i need to know were the positive and negative wires go when puting back together

Hello, What engine please? The 2.5L has a Bosh starter and the 4.0L has a Mitsubishi starter.

There are no negative wires that connect to the solenoid.

Roger

its a 4.0 liter

i got the starter in solenoid in place in hooked the wires back up and nothing is happening

Diagram I have shows positive battery cable connected to large terminal of the solenoid and a small wire eityher Brown or Grn/Wht connects to the "S" terminal on the solenoid.

How does this differ from your connections?

Roger

well the aftermarket one I have both terminals are the same size, i have the positive where it was on the old solenoid, there is a wire coming off the starter that connects with the negative cable and then a small terminal that has a one small say 14 gauge wire on it

I do not see this wire you speak of that connects with the negative cable. Where? On the engine? What color is it and how large an end terminal does it have? Can you tell where it leads to?

Roger

Bedtime here, I'll check back in the morning.

Roger

I'm checking in with you. Have you traced this wire yet?

Please update,

Roger

1993 Jeep YJ-Series All Part Groups   

I have a 1993 yj 4 cyl jeep, my water pump was leeking and the top of my rad. I was in the bush and on the way home it made my motor wet. I fixed my rad and my water pump. My motor is boging at a low idel and surging when the rpms go up. Can you help thanks

First thing to be concerned with is the condition of the piston rings and head gasket.
Overheating can cause the rings to lose their tension, resulting in lower compression.
First thing on the agenda should be a dry compression test, followed by a wet one.
If not sure how to do Google it and it will be explained.
You are looking for comp aprox 140 psi, with no more than 10 psi difference. If one cylinder low, do a wet test, if compression climbs, then there is a ring problem. If two adjoining cylinders are low, that may indicate a head gasket leak.
If you get a compression tester , get the screw in type.

1992 Jeep YJ-Series Fuel System   

IDLE,S GREAT,RUNS AS THOUGH IT SHOULD READY TO GO,THEN WITHOUT WARNING IT WILL MISS AND BACKFIRE,i WILL DOWNSHIFT AND SOMETIMES IT WILL CLEAR ITSELF,OTHER TIMES IT WILL MISS A FEW TIMES THEN IS OKAY AGAIN FOR AND UNDETERMINED TIME. i HAVE CHANGED THE PLUGS,WIRES, DISTRIBUTOR CAP,AND THE ROUTER,STILL IT MISSES ,MAINLY AT DRIVR SPEEDS. eD

eD,
I would suspect a failing oxygen sensor. These Jeeps are common for giving these symptoms when an oxygen sensor is failing. If it is 16 years old, it is a good time to change it anyways.

1991 Jeep YJ-Series Engine Won't Start Happens always Always

Hello

My Jeep YJ is a 2.5L MPI 1991 Euro version (not have a check engine light)

My engine only start when i add petrol in to the throttle body. When the petrol end the engine turn off (in this five seconds engine sound good).

I have fuel pressure on the ramp but the injectors donīt open.

The injectors not recive electric stimulation

I revised the wire connection near of the injectors and it is fit good

Thank you very much

The first thing you'll need to do is determine which is missing, the key on positive feed to the injectors or the 'pulsing' (on and off switching) negative feed from the computer. The key on positive voltage is likely fused. Let me know and we'll go from there.

Hi
The splice of the injector has electricity, but it has positive in both sideburns...

The crankshaft position sensor have a tree wires, how I know if it donīt work??

Thank you

As a general rule, if the crank sensor is bad there will not be spark to the spark plugs.

Did you use a digital volmeter to check for voltage to the injector?

Yes, I use a digital volmeter.
The results were of 1.7mV one and other one 1.9mV both positive.

Thank you

You need to set the scale on your meter to aprox. 20 volts DC and retest for positive voltage with the key on.

You can use the following link to access a repair manual that'll contain wiring diagrams and test procedures- I assume most things will be the same excluding the check engine light-

http://autozone.com/servlet/UiBroker?UseCase=RG001&UserAction=viewRepairGuideYMMEYear

Hello

My Xray-scanner read trouble codes are 33 but my car never had A/C

Thank you

Does the fuel pump run when you first turn the key on and during engine cranking?

Yes the pump work

It is really looking like a computer or sensor input to the computer at this point.

This engine, I assume, has a distributor- the problem could be in the distributor itself.

Also check battery cables and engine grounds thorougly- this can cause a crank no-start condition.

1991 Jeep YJ-Series Electrical / Lighting Systems Won't Start  

my jeep won't start is something with the coil distribuitor, I replaced it but is not getting any power ????

Hello,

Which engine do you have?

What did you replace, the coil and the distributor?

By not getting any power, do you mean key on battery voltage to the coil OR you are missing spark to the spark plugs?

1991 Jeep YJ-Series Ignition System Won't Start When starting Always

I have no spark changed the coil still no spark can you help?

Have you checked the crankshaft position sensor?

Use the following link to access a repair guide that'll give test and replacement instructions-

http://autozone.com/servlet/UiBroker?UseCase=RG001&UserAction=viewRepairGuideYMMEYear

Let me know what you find or if you need more assistance.

No I will check it next. I checked the cam sensor in the sistributor it good!

Do you have the 4.0L engine?

its 2.5L

Do you get a check engine light with the key on (as your normally do)?

Make sure the distributor rotor is turning when you crank the engine.

1991 Jeep YJ-Series Fuel System   

My jeep is not getting fuel to the engine . I have replaced the fuel pump, fuel filter, the fuel pump relay and auto shutdown relay. That fuel pump was bad, so I had it done at the dealer. Now the same thing is happening. I checked voltage at the plug going to the pump. There is an intial 12 volts then as I began to crank on the engine it drops to 10.5 volts. It will not start. Is the voltage drop normal? What could be causing the fuel pump to keep going out?

Hello, I would expect the system voltage would indeed drop on any system on the vehicle if you monitored the voltage during cranking. Yes, I think that is normal.

What is the fuel pressure reading? Do you have spark while the engine is cranking?

Do you have a warranty on the dealer repair of the fuel pump replacement that would help here?

Roger

1991 Jeep YJ-Series Chassis / Suspension & Steering   

I just replaced the brakes on all four wheels, calipers, rotors, pads, brake shoes, wheel cylinders, and master brake cylinder. I bled the brake lines and when I pump the brake pedal I feel the back pressure, but if I release the pedal and wait awhile and press it again the pedal goes to the floor. Why would the pedal go to the floor. This is on a 1991 Jeep YJ Wrangler.

It depends on how you bleed the brakes Are you using a two person system/
You start from the cylinder furthest away from the master cylinder and work your way to each wheel ending at the closest to the master cylinder.
Have someone to pump the brake until they buil up pressure and hold it at that pressed position until you release the air/fluid from the cylinder and tighten it up again {before they release their foot}
You then repeat the process for the remaining wheels.
Finally you bleed the master cylinder
You should be fine after that.
if after you do the bleeding and the same thing occurs then you still have a master cylinder problem.

I have done the two person method and started from the furthest to the closest. I have clear brake fluid coming out of all four brakes. No bubbles. I guess I have not bled the master cylinder. How would you do this, I do not see a bleed valve. I guess this could account for the brake pedal going all the way to the floor. Also this is a brand new master cylinder.

Yes that is how you can tell that it is the master cylinder by the symptom that you are expereincing.
if there is no bleed valve you can prchase one and put it in or you can do it by lossening the brake line going to it and tighten it the same way you bled the others
this will take the place of your bleed valve
after that you should be fine.

1991 Jeep YJ-Series All Part Groups   

jeep seems to hicup during acceleration while its warming up once its warm it doesnt

2.5l 4 cylynder manual

Try checking the coolant sensor to see if it reads off at all.

When was the last complete tune-up?

Any check engine light while the engine is running?

the last tune up was awhile ago i would guess the vehicle is new to me

There has been no check engin lights

1990 Jeep YJ-Series Engine   

I am trying a what i thought was a simple engine swap. I was putting a 94 engine into a 90 wrangler. Both a four cylinder five speeds. But when i was looking through parts catalogs for worn-out parts i realized many of the parts are not compatible. How do I know what parts need swapped before i try putting in the newer engine?

According to a Hollander Interchange database:

The 4 cyl interchanges from '86-'90 model years. And starting in- '91 through- '95 interchange.

The interchange lists the cylinder heads as the same but the blocks as different. I'm not saying you can't use the engine, just that for some reason the interchange does not include the engines as swappable as a whole. If the engine will indeed bolt to your tranny, you'd have to inspect components, mounts, wiring connectors, and electrical components individually to see if they are compatible.

1989 Jeep YJ-Series Ignition System Hesitating When accelerating Always

Hello, When I accelerate from idle the engine bogs, whether from a stand still, or rolling. I did a tune up and replaced the vacumm lines. What else should I be looking into? Thanks

Did you change the fuel filter?

Does it make a difference if the engine is cold or warm?

Have you checked for troublecodes?

fuel filter has been changed, OBD 1 not on this vehicle, it uses two standard Molex 6 and 15 pin for analog voltage meters

If the engine is worse when it warms up check for restricted exhaust (plugged cat. converter).

If the engine temperature has little effect check for adequate fuel supply (pressure and volume).

Which engine do you have the six or four cyl.? I will need this to see if there are any bulletins that apply.

I have replaced the cat, and the muffler. I also installed a new fuel pump.

Check for vacuum leaks.
Check that the ignition system is not breaking down.
Then have the carb checked out, I assume you have the six cylinder.

All the vacumm lines were changed, the intake was tested with a soap solution, a vacumm line, and a propane feed. The iginition coil, distrubutor cap, rotor, wires and plugs were changed.

Next steps:

Check any wiring harnesses that may be put under to much stress when the engine flexes upon being put in gear.
Check to make sure the egr valve is not opening to soon (disconnect and test drive).

Beyond this it appears to be a carb or engine control problem. Consider an aftermarket carb if your state/local emmissions laws will allow it.
Edit, Copy, and Paste this link into your address bar, it should be helpful.

http://www.off-road.com/jeep/tech/258bbd/index.htm

1989 Jeep YJ-Series Ignition System   

i have an 89 wrangler with a 2.5L inline 4. It will start up and run for a while but after about 10 minutes it shuts off and wont start again for some time. It has something to do with the electrical system because the motor is getting fuel. I dont have a pick up coil in the distributor and i have replaced the cap, rotor, wires, ICM, and ignition coil. The only thing i can think of is that it is some sort of breaker or relay. Maybe the ignition switch?? PLEASE HELP!!!

First things first, check for spark to the spark plugs during the no start period. Alternatively spray a small amount of carburetor cleaner into the throttle body during the no-start period and see if the engine will start (even if just for an instant). You may still have fuel pressure, but this don't mean you have injector fire.

thanks man, the plugs arent firing during the no start period.

Next check for key on battery positive voltage to the ignition coil and the fuel injectors (negative lead of meter to a known good ground and the other to the components mentioned above).

well as of this moment i dont have a voltometer or ohmmeter, is there anything else i can check?

Not really, aside from jumpering the positive side of the coil and seeing if it will start.

how would i do that? also, if the icm is good what other possibilities could there be? could i have a bad computer?

Bad computer, ignition switch, distributor, wiring, etc. It is usoally cheaper, in this situation, to diagnose the problem than to replace parts (even if you have pay for diagnosis). Unless you have a donor vehicle to swap parts from.

Have you checked the disributor?

not the distributor itself... but i have just replaced the rotor and cap along with all the plug wires. when its dead the distributor gets no spark from the ignition coil. i have another ignition coil that i swapped out to see if it was the problem and it still didnt fire up. man, im so confused

also, is there any way to test the ignition switch? For example, could i unplug it while the motor is running to see if that kills it?

There should be a crank sensor in the distributor (hall-effect) that may also be going bad.

No, unplugging the ignition will not prove anything. There is really no tests you can do without test equipment.

1989 Jeep YJ-Series Engine   

Hi,

I have a 1989 Jeep YJ that always start very well when cold, but the engine can stall at anytime, either while driving on the highway or just stop warming it up in the garage. I then have to wait up to one hour (normally 20 minutes) to get it started again. I have changed the carb, fuel pump, distributor, cap, rotor, coil... and the problem is still there.

It even did something very strange the other day, the engine stall and then 5-10 seconds later without touching anything, it fired up again...

Would you have any suggestions on what the problem could be?

Did you replace the pick up coil in the distributor (may be called a hall effect sensor or crank sensor on your Jeep)?

This can create a no spark situation. Have you checked for spark during the no start period? It is critical to check for spark so we can determine if this is a problem with spark or fuel delivery.

I'll assume the fuel filter has also been ruled out.

I am not entirely sure about what you are talking about.

I have checked and there is no parts available with the names you gave me for this specific car.

I have basically changed the distributor, rotor, cap, wiring to the spark plugs and the coil. I thought that this was everything. Is there another part? Where and how I can i find it?

The fuel filter was changed indeed.

Thank you.

Which engine do you have?

4.2 liters

Copy and Paste the following link into your Address Bar for reference. It contains the pick-up I mentioned-

http://www.partsamerica.com/ProductList.aspx?parttype=200&ptset=A&searchfor=Pickup%2fStator

This is a common cause of the problem you are having, did the new distributor have this already installed?


If this has been replaced new, the Ignition Module is next on the list-

http://www.partsamerica.com/ProductList.aspx?parttype=194&ptset=A&searchfor=Ignition+Module%2fControl+Unit

Replacing the ignition control module did solve the problem, thank you for your help.

1988 Jeep YJ-Series Fuel System Malfunction Happens always Always

Fuel Gauge suddenly stoped working. Was told to check the connection on top of the gas tank, any suggestions?

Yes, it could be a loose connection on top of the tank, or more common is a bad float in the tank.

Thank You,
How difficult/costly will it be to repair the connection or replace the float for the tank?

The float could cost several hundred for the repair. If it is only a bad connection on top of the tank, I would expect a $50-100 repair. I use a test light connected to ground and probing the fuel sender wire to see if the gage is working. If it is, you can track it back to where it stops, most likely in the tank.