89 Manche runs 30 sec, sputters, then dies

[Sugarfoot]

:agree: I think your off on a wrong tangent and you need to be careful with what your rewiring. Before you do more damage than good hot wiring etc. Remember KISS: keep it simple stupid.

 

Someone on this site has got to have an 89 with a 2.5 that can tell you where the voltage resistor is for the fuel pump? Wish I could help but I'm 4.0 and mine is where the photos show it is on the 4.0.

 

Don't jump for the power source. Pull battery, clean connections then install test battery.

 

Not rock on, it's Hook em Horns!

[ocean]

I wasn't planning to start with hot wiring just try it -after- examining the fuel relay switch... I bought one and a multimeter and I will see where they take me.

Temporary removal of the fuel relay switch and jumpering the wires so that my fuel pump gets power, though protected with an an inline fuse in the wire I'm using to jumper, will tell how good my grounds are. If that worked and the truck ran then I would be off to check other items like wiring :nuts: TPS and such.

 

 

Thanks for answering the engagement of the secondary systems question I had . I also agree that I don't want to go hacking into perfectly good wiring (possibly compounding my issue without solving anything.)

 

I have researched through the posts on this forum and somone else had a nearly identicle issue with the same things going on that I have and it was his Ignition Control Module.

 

on the low tech side

 

I have wondered if a peice of debris is in the gas tank and its obstructing the fuel flow.

 

 

Please tell me if there is an easy way to clean the oil and dust off the wiring and terminals under the hood?

 

Thanks again

[Wildman]

To clean up just the wiring, you could use some spray on engine de-greaser, and wipe it off. For any connectors / terminals, you should use Contact Cleaner. That will blast any dirt / grease / debris from the connector, and evaporate quickly. Any connectors that you take apart, apply some dielectric grease to the fitting before you re-connect it.

 

This is a possibility that your sock filter could be 'plugged up' with rust scale within the tank, here's a picture of the in-tank filter / pump / sending unit-

 

 

One way to "test" the fuel pump is to disconnect it at the filter inlet, add a piece of fuel line to the input line, put the other end of the line into a empty gas can, and turn the key to "on", this will show you if the pump is running, and if it is 'spitting' and also will show you if possibility any debris are getting thru the pump. Run the pump for some time, to like pump a couple of gallons into the gas can.

 

Of course........Use extreme caution when doing this. like do it outside, no cell phone to your ear, no chance of any sparks/pilot lights near by.

 

This will also give you a chance to change the in-line fuel filter.

 

Another question, that I don't know if it was asked........How fresh is the gas in the gas tank??? couple days old, couple weeks old, couple months old???? Gas only has a shelf life of a few weeks, unless stabilizer was added to the fuel in the tank......when it was fresh.

 

As far as getting into the ignition control module, first from what you have been writing, it sounds more like a fuel issue your having problems with, start with that issue and solve the possibility's that is not an issue with your truck. Then you can back track to other issues that could be causing the 30 second run cycle that your having........it could be as simple as the ignition switch being bad, and cutting out, but from what your writing, it sounds like a fuel supply issue.

 

Try that fuel pump test first, see what the fuel pump is doing, and if the fuel pump is not preforming right, or you don't have proper fuel pressure, then the pump is going, or plugged.

 

K.I.S.S.

 

If you want to, go to this Link Where Taz posted the FSM, and look up page 14-5, this will give you the info on the TBI system that you have on that 2.5.

 

Basically, "TBI fuel pump controls - Voltage to operate the TBI fuel pump is supplied through the fuel pump relay when the relay is grounded by the Engine Electronic Control Unit (ECU)"

[ocean]

:agree:

That Renix FSM link is the sh.... uh, er, yeah its kick butt lol! :smart:

I've been doin my book learnin and studying the systems and the troubleshooting as nauseam, (though in a strange way it has been entertaining. :nuts: )

Anyway I have been learning the methodology from all of your posts, and I really apreciate it. This is a great forum. Each of you has taken my problem on to help me. You can't find that in many places anymore!

 

So the gas issue.... PO says it was a couple of weeks old.... :brows: So the first thing I did was put some heet in the tank.

 

I will check and replace the inline filter first.... if its got a rust issue I should see debris and be able to check flow while I am in this location.

 

On a happy note I purchased a small cordless soldering iron, love new toys, and will be looking over all wiring as I go from the fuel system jumper to the tpc harness, to the cps harness, and down the line.

Its got some extra wires (2) running around... I really hate wires that just lay disconnected in the engine compartment with duct tape (yuck) for protection.... Looks like they just pulled this, wired that, replaced this sort of a thing which has led to a small issue of the original issue never being solved,.. naturally this issue would have cost less to solve in the long run... so instead it causes a lack of electrical integrity and component/circuit failure...thats why they never did it. :dunce:

 

Yeah KISS is the way. BTW is automotive wiring stranded, and is it made to tolerate greater heat, and thus available at Lowes for less moullah? I went to Autozone (its closest) and paid through the nose.. :( .

 

:wavey:

[Redramman]

I don't know if it's the same on a Comanche ,but when my Ram had same problem it was a bad crankshaft position sensor.A computer scanner/code reader might hint at problem if engine light is on.

On second thought when crank sensor went it would not restart unless you disconected battery to reset computer so that might not be your problem. :dunno:

[BLHTAZ]

I don't know if it's the same on a Comanche ,but when my Ram had same problem it was a bad crankshaft position sensor.A computer scanner/code reader might hint at problem if engine light is on.

On second thought when crank sensor went it would not restart unless you disconected battery to reset computer so that might not be your problem. :dunno:

His is an '89...it has no computer that stores codes or that can be reset ;) . The Renix ECU is a fresh boot on every start-up.

[ocean]

It LIVES! :bowdown:

 

So, today I actually have time to get under the hood. I degrease the engine and wiring so I can see what I am looking at. I went through connections and put dielectric grease everywhere that could be an issue... Fuel relay, power relay etc. After jumping the fuel pump I know it works fine... its a spark issue.

Doesn't want to start... at all. I try starting fluid into the tbi... nothing.

I call the PO and find out the he replaced the dwell? inside the distributor cap, the spark plugs (he put new autolites in it)...nothing else.

I go to checker auto and by another coil. I install it and get to looking at the spark plug wires... they are the OEM wires... Hmmm.

 

I go buy a nice set of Bosch wires, and a new distributor cap. It cranks up and purrs happily.

 

I guess its always back to basics :thumbsup:

 

I ran seafaom into the gas tank and took the last third of the bottle and put it into the crank... now its nice and quiet... I take in on a test drive... good. I drive it down the highway, at 85mph and return the 120.00 worth of parts I don't need. :banana:

 

All I have to do now is get the body to stop creaking.... Lift kit and 4wd in the spring I am thinking. The muffler weld mount at base of engine is broken so I am going to use a hose clamp to tie it down for the short term to keep it from rattling. Aside from other minor mech issues, cosmetic issues, needing new paint, and cleaning the dirt from twenty years of service I couldn't be more pleased.

 

Thanks for all of your advice and support.... There's only one place to come to for advice.... You guys rock! :clapping:

[Wildman]

I guess its always back to basics

 

 

Yes is is.............K.I.S.S. :yes:

 

I call the PO and find out the he replaced the dwell? inside the distributor cap,

 

Well.........close, it's actually the Cam Position Sensor.

 

So......all this problems with it running.......came down to the spark plug wires :shake:

 

All I have to do now is get the body to stop creaking....

 

Hopefully it's not the "body" creaking (it's a Uni-body / Frame combination) cause that would be a bad thing.......it's more than likely the 20 year old suspension you hear creaking, like all the 'old' bushings in the leafs, control arms.......and the springs from sitting for some time.

 

Easy fix........New suspension with the lift, Or........a boom box stereo

 

So, it's running, It' driving........now it's time for- :needpics:

[BLHTAZ]

Glad to hear that it's running again :thumbsup:

 

The only thing I can see that I would have done in addtition is to get those Ford plugs out of it. I am honestly surprised that it is "running good" on Autolites as out trucks usually don't run well on anything but Champion or Bosch.

[ocean]

I would say that the coil needed to be replaced (30 sec run issue it cost 56.00.... BTW they had 2 types listed- one was for non-US I'm guessing South American/Canadian Jeep?). The wires to the plugs weren't hot enough anymore, (21.50 for a new set). The distributor cap had some corrosion on the points, a new one (12.00) and its all good.

 

A little die-electric grease (15.00 for large tube) and we're good for now. I was surprised about the autolites too... I wanted to replace them but I didn't have the proper spark plug adapter for some reason. (So we recomend any special plugs? platinum bosch or just plain old copper champions?)

 

:typing:

While the original radio still functions I will be installing a CD-MP3 player, already have it, and speakers sometime in near future. I plan to install newer tailights (maybe LED?), and others to match, as the fixtures have broken down on the originals. Interior lights to be replaced with LEDs. Some new material on headliner. Interior updates. Dark blue exterior paint. Tinting. New (2 me) instrument cluster w/tach and gauges. Brake booster upgrade from a 95(1st thing to do...going is good -stopping is better). Rock guards on lights. Brush guard. Tinting... :rant:

 

I need to fix the back passenger bumper quarterpanel area as it is dented up pretty good from PO's backing misadventure,.. I could cut it, but I don't need to at this point. I want to to remove the cap and put in a bedliner.. suspension/lift (not sure what size just yet)..4x4 conversion :bowdown: (its a change of religion for a 2wd truck... might just get another for trail stuff) ...yada yada yada.

 

I'm just happy its running.... incidentally I like the inline four cylinder, why does everybody bag on it?

:cheers:

[Wildman]

I'm just happy its running.... incidentally I like the inline four cylinder, why does everybody bag on it?

 

There is really nothing wrong with the 2.5 engine, just that once you feel the difference of the 4.0, you never go back :yes:

 

My first '89 MJ 2wd was the 2.5, with the BA-10, getting around town, not a problem, hitting the high way, 50-55 was a struggle, going up a incline, had to drop to 4th to keep up with 50mph :oops:

 

Next MJ was the 4.0, and all the rest are 4.0, I will not go back :D

 

just plain old copper champions?

 

Yes, think about this, the engine is 20 years old, the ignition system is 20 years old, the sensors and ECU are 20 year old technology, Kind of before the platinum plugs were really on the shelf.........Older engine, stick with the older technology.

 

Platinum plugs........I lost a Ford 302 engine to these, it's amazing what that little piece of steel can do to the top of a piston :fs1: I wouldn't install them in any engine, even if someone gave me them for free.

 

I was kidding about the boom box stereo, as to 'cover' the squeaks you have :roll:

 

I plan to install newer tailights (maybe LED?)

 

Ah, yea, as soon as you find these, let us all know, the MJ Taillights have not been made since 1992 :roll:

 

Get your mechanics squared up first, like replacing all the 20 year old seals and gaskets, and replacing worn out bearing and u-joints, then plan on the glamor upgrades :D

[BLHTAZ]

Yeah...stick with the Champions on that engine. As Wildman said, the Bosch Platinums are for the slightly newer engines. I run them in my YJ and in my '02 Dodge Ram 4.7L as they are the recommended performance plug frmo Chrysler ansd they are what you get if you order Mopar Performance spark plugs. I am a 100% believer in Platinum plugs, just not in older engins.

 

As far as the 4cyl thing, the 6cyl (4.0L) has more power...and A LOT more torque as well as a much longer, more dependable life.

[Eagle]

The only thing I can see that I would have done in addtition is to get those Ford plugs out of it. I am honestly surprised that it is "running good" on Autolites as out trucks usually don't run well on anything but Champion or Bosch.

I agree on dumping the FoMoCo plugs, but my 4.0Ls seem to like NGKs best.

[BLHTAZ]

Yes...I forgot that there are certain years of the 4.0L that came with NGK's from the factory. I think it was the '99 - '04 range, but not 100% sure on that one...

[ocean]

Well,

 

I agree about power, torque, and the beuaty of the symetry of a straight six... its perfectly balanced. Its got power, its got balls. I wouldn't mind having one around for fun stuff... been looking too!

I had my 77 cherokee and I would give my left nut to have it back (mind you it would have to be showroom, built, and perfect!). It had a straight six that would eat most 8 cylinders for breakfast. It got amazing milage and I loved it..... three speed stick, a sick growling olive drab beast, people fled the lanes as I drove down the interstate, it was almost straight out of mad-max... whats not love?

 

With the little manche in the year I have obviously their are obstacles and limitations. I am not beyond being able to appreciate the simplicity of its 2wd economy design and the functionality. (My wipers and windhield fluid sprayer all still works how cool is that! Even the fan works on all settings LOL.)

As far as longevity at 221k and running smooth (finger crossed) I can't complain. In my area there are many vehicles, including cherokees with l6's, that have less miles and no longer run. Its all about how their cared for.

 

I agree about the tech points of the champions for that year. They didn't design the engine to handle hotter plugs to begin with... why overkill it.

 

I also love not having a cramped engine compartment. I want to remove the mech fan and replace with two electric aux fans from cherokees - it should give me a little hp boost. Add in a better flowing exhaust and better air induction.... I like clean smart, simple setups that I can take down myself without a sweat when the time comes to do a rebuild.

 

I don't know that I am a purist by any means but I am all about improving functionality... genius can be defined by simplicity, especially in the realm of design... its art really, just another form of it.

 

So 2wd to 4wd, with three inch lift, will cost me what on economy in the 4 banger? I'm guessing it would easily put me into high teens. (I'm currently getting mid to upper twenties... PO said 30 but IMHO thats optimistic) BTW the truck gets up and runs at 85 down the interstate... it just takes it a little longer than others.

 

So obviously I'm thinking I'll just have to find another thats already got the 4.0 and build it.

 

LOL can I offer you my

[Eagle]

My first '89 MJ 2wd was the 2.5, with the BA-10, getting around town, not a problem, hitting the high way, 50-55 was a struggle, going up a incline, had to drop to 4th to keep up with 50mph :oops:

AX-5 or T-5 maybe, but the BA 10/5 was not used with the 2.5L engine.

 

Platinum plugs........I lost a Ford 302 engine to these, it's amazing what that little piece of steel can do to the top of a piston :fs1: I wouldn't install them in any engine, even if someone gave me them for free.

Agreed. I've heard too many stories about that little platinum tip breaking off and holing the top of a piston to ever consider using them in any engine I own.

 

I run standard (not platinum) NGKs and I think they are better than any other plug for the Jeep engines.