Hi folks...

Thought I would come here and see if anyone could help me out. My truck (91 Ranger, 2.3 liter, 146,000 miles) left me stranded while I was on my way to work. I had a hard time getting it started, and once it did start, it wanted to stall out when I pressed the gas pedal. My first thought was that its either the fuel pump, fuel filter, or both. I went ahead and replaced the filter because it was long overdue and then checked the fuel pump and it was fine.

I pulled the codes and got #28, #88

#28 - VAT sensor out of range.
2.3 L Cyl ID, IDM low or right coil pack failure.

#88 - Throttle kicker solenoid
Variable voltage choke relay circuit fault
Fan control circuit fault
Electronic ignition- IDM, DPI, or spout circuit failure.

Out of curiousity, I pulled the right side coil pack off and noticed the bottom was cracked open with a dried white substance hanging out of it. Figuring this to be the problem, it was replaced. The truck ran great for one day, no skipping, no problem starting, and no computer codes. The next day, I cranked it to let it warm up and it ran for a few minutes and quit. I tried to crank it and it wouldn't. I checked all the fuses and relays, and they were all ok. The fuel switch on the passenger side floorboard was ok.

Is my Ranger on deaths doorstep?

Thanks in advance.

 

wgea, your ranger still has a lot of life left to her. I've got 311,000 miles on mine, and I'm about to take it on a 300 mile round trip to the southern part of Ohio.

Alrighty. Something is going bad in the ignition process. Let me explain how it all works. Behind your alternator, mounted to the intake manifold, is a computer pack that says "motorcraft DIS." This computer has a plug on the bottom and top, and picks up information from the crank sensor to determine when to fire the 2 coil packs, and when to fire the injectors.

I had a problem with mine about a year ago. I would be driving along, and it would try to die, like it was running off of 2 cylinders. After I researched all of this, I decided to play with the connections going in and out of the DIS. I wiggled the top plug one day when it was running off of 2 cylinders, and it came right out of it, and ran like it was supposed to.

I pulled the DIS pack off, and swapped it with another ranger I had. I might want to note that you HAVE to have a screw in the bottom left of the computer pack. This screw grounds it out. Since I replaced it, I have had no problems whatso ever.

So this is what I'd do. Replace the other coil pack underneath the alternator while you have it all apart. Have your DIS tested at your local parts store, I think auto zone or advance will do it for free. If it's bad, buy a new one, or hit a junkyard, because most are loaded with ranger engines. Make sure the mounting plates for the coil packs are clean and shiny, so that the coil pack can get a good ground.

In my honest opinion, I think you have a DIS computer pack problem. I've seen them get water in the top plug and short out intermittenly. The reason I think this is the problem, is because it uses the exhaust side coil pack on start up, and then uses both while running, although it will only need one or the other to run. You can unplug one coil pack while its running and it won't die. Startup like I said earlier NEEDS the exhaust side coil pack. SO basically, both coil packs wont fail at the same time, but the source of firing them will. Hope this helps.

 

did you take the neg cable from the battery to reset the computer. if not, try that first.

 

Interesting... I didn't know the mounting surface was a ground.

I appreciate the info Handyman43358. I'll post the results ASAP.

Thanks again...
-wgea

 

No problem buddy. According to the diagram I have somewhere on the whole DIS circuit, it indicates that the mounting surface for the coil pack is a ground. Since the coil pack is really a computer in itself, telling which spark plug wire to fire off, it makes sense.

Please post ASAP. I'll be around all week on here during the evenings if you need any help!

 

Finally got an off day today...

I traveled around to different parts stores looking for someone who could test my DIS module. Mine seemed to be the only one they ( o'reilly's, autozone, advance auto, and bumper to bumper) couldn't test.

Is there a way I can test it with a multimeter?

 

Honestly I don't know. I dont think theres any way you can test it. If it was something simpler then you probably could.

If you have a junkyard nearby, or even a buddy with a ranger, I'd swap them and see how it acts.

 

I found a motorcraft dis module at a junkyard today. I installed it and the truck is running fine except for ...

Code 41 (Key on engine running) "System lean"
I suspect this may be because its been sitting for a few days (?)

code 18 (key on, engine running) ""Check base timing & advance function"

Im going to get the truck back on the road this evening and see if maybe it just needs to "run around in the pasture" some. I'll keep you updated.

 

I would clear all the codes and see what comes back before doing anything else. If you need the pinpoint tests for the codes just drop me an email.

 

I agree. What year did you get it off of? I got mine off an 89 (mines a 91) and its doing fine. But Ken is right, clear the codes.

 

It came off of another 91 model. I cleared the codes, took her for a spin and all seems to be well. I checked the codes again and none are available.

Thank you guys, Your help has been valuable and is much appreciated.
wgea

 

Thats great. I had a feeling that was probably your trouble.

I might want to stress that it will take a while for the computer to relearn the engine. I think it takes like a half hour of driving time for the computer to adjust everything to where it should be. So don't get too excited until you drive it a little bit. The computer wont throw a code until it knows exactly how the engine is supposed to run. If it does end up having codes, you know where to turn for help!

 

In an other topic, I am having a simular problem. I am getting a code 48 Loss of IDM, left side. I just had the engine out, is it possible this could be it. I had the coil mount off, but the coil stayed bolted to the mount. I have cleaned and reseated all my connections, replaced the plugs and wires. Checked for spark form both coils. It is coughing and choking under load, and blowing a little black smoke.

 

Hmm.. Sounds like you might want to check the fuel pressure regulator. Check your fuel pressure, you should have I believe around 40 PSI at idle.

Actually give us more info. What year/engine... all the goodies.

Did you pull the KOER (Key on Engine Running) codes? Or the CM (continuous memory) codes? If you did it with the truck running, then your code was actually 48: Air flow measured too high at base idle. If thats the case, your mass air flow sensor could be bad (if you have one.)

 

89 Ranger with a 2.3 Dual Ing Coils(No Dist). Code is the same KOEO or KOER. Clear the codes, and the first code after 11 is always 48 Loss of IDM, Left Side.

I have replaced (with new) Plugs, Wires, and Oxygen Sensor. Cleaned and checked all my connections. Before I cleaned the connections, I was getting a rash of codes that made no since. But his one I am stuck with.