I have a starting/running rough problem with my 92Ranger 2.3L. And I can solve it by "wacking" the DIS module with a screw driver? What gives?
I forget the code, but the check engine light comes on. Also on startup it generally runs for a moment and then dies. And when I restart it keeps running but maybe rough with the check engine light on until I get out and whack the DIS module etc. I've had pros check this out and wasted money. People don't seem to know??

Is it 2 problems:

1. some sort of grounding problem with the DIS module? I don't mind getting a new one, but I've "heard" that the replacement can vary from year to year etc and people that replace them often have even more problems? Otherwise I'd just go buy a replacement--but would the NAPA dealer or whoever-give me the correct module? I don't know. I live in a rural area and the Ford dealer parts is not pleasant unless one has a really new car. They're not at all helpful. I'd rather not go to them. I have the original DIS module with 250Kmiles. Is that bad? I'm the original owner. I've rebuilt the motor etc/+ other stuff,but never changed the DIS module. Or do I just need to remove it--and clean the mounting area. I believe that may be the ground/don't know.

2. do I also have some sort of damaged computer? I understand the starting problem such that on the second start it runs probably after the computer has moved to some sort of factory default setting etc But what causes it to do that. My sensors seem OK. Maybe its related to the DIS Module problem?

I live in Napa Calif and have to get the truck smogged every 2 years, and in my case that's at the end of May. I've had this problem for some time. If I can't resolve it. Its gonna be a big problem. They're not understanding in the BayArea smog check world.



Appreciate any help

Thanks

 

As a followup to my question. I've removed the DIS module which is held with 3 screws to a plate part of the intake manifold. I don't know anything about this, but intuitively I'm guessing from the looks of it that this is a ground mount type of thing.

The back of the DIS is approx 3"x5" and is a clean metal flat surface covered with some sort of whitish cream like material. And the flat mounting surface of the intake is the same with cream also. Maybe its just a problem with the ground? Maybe I just need to clean it and reapply the cream.

I've got some books, but I don't see it.

Does anyone know what this cream is?

I'm off to NAPA I'll bring the DIS with me and see if they have some sort of similar gel for a ground. I've got dialectic type grease--but its clear not whitish--Is this something I could use?

Tom

 

It's a thermal compound, also known as "heat sink grease".

 

Oops, forgot to mention: the DIS is grounded through the screws, so correct mounting is indeed important.

 

Really. That's good to know. I just got back from NAPA, but they didn't have anything called that in stock or as an image on their computer order screen, etc but he did mention from his notes the exact term you mention. "heat sink grease". And I'm saying I went there before I read your post etc.

So I read through my Chilton book again and it is of course "very broad" on specifics like this, and they said to "Apply an even coat approximately 5/16" (0.8mm)--(that's gotta be a typeo!! 5/16" thick?-i don't think so--yes for sure 0.8mm sounds right/not 5/16inch) of a suitable silicone dielectric compound".

So I did that. I wiped both the module and the mount on the intake clean with a chemical-and then rubbed lightly with a very light abrasive cleaned again and applied a thin even coat of a general purpose clear silicone dielctric compound to each surface and reattached.

I started the truck and it seems fine--no check engine light--seems to be running OK, but this has been a long time intermittant problem. So I'll need to check early tomorrow morning when the temps--it and the environment are lower. Both lower temps and a moist environment "seem" to bring it on.

"Heat sink grease" uh? That's interesting. The NAPA store was reminding me that usually replacement modules come with the needed compound etc. And they like you both mention this term-heat sink. I thought this was a ground. Is it? Or is it both a ground and a heat sink? It looks bigger and different than most modules I've seen. But I haven't seen them all for sure.

Thanks for your help. I appreciate it. And one more thing please-I guess with this model 92Ranger I'll have to go to a repair shop to get the Trouble Codes erased. I'm guessng the check engine light has brought on a Trouble Code. It doesn't go away just by unplugging the battery for a time does it? Because in this county if you have any activated trouble codes when you get your smog check--Test Over--you failed etc and there's no quick "retest". One has to go onto another level of testing etc.
Especially an older car like my 92 truck. I have to go to a "test only" station that is directly hooked up to the State's computer network etc. and they monitor the whole thing. And believe they stay actively involved. Its quite a system. And the last I heard there weren't any Code Checking devices that cleared the codes in my computer. I know newer trucks are different maybe and for newer systems there are inexpensive code checking devices that can reset trouble codes, but I don't think my truck has any such options. Would you be aware of any of that? I've got an inexpensive "beep"/light type code reading device, but that's all it does.



Tom

 

You can find heat sink compound at computer and electronics stores.

Trouble codes can be erased by disconnecting the battery for 5-10 minutes.

If your problem persists, then it's probably a faulty DIS module.

 

There is heat sink compound and dielectric grease they are not the same. The heat sink compound is the white stuff you mentioned. And as Rockledge said is avaliable at computer stores. I get mine from my alternator / start parts vendor. I helps transfer heat away from the module. Also check the multi-pin connector on the module for corrosion on the pins. And use dielectric grease on it when you reconnect.

 

Heat sink compound~ Oh that's funny. I use my computer a lot and I assemble my own machines--I have heat sink compound. I use it when I install the cpu. lol

My hobbies are "overlapping". I'll reinstalling with some of that stuff. In fact that is what the old dried material that I cleaned off looked like.

Thanks for your help.

Tom

 

Your system is pre-OBD-II, so a regular EEC-IV tester should be able to show any codes, and erase existing ones. As noted, disconnecting the battery for a while will erase the codes, but you can speed it up by stepping on the brake pedal, leaving the door open to enable the courtesy lights or turning on the head lights. Any of those actions will attempt to use the 'keep alive' memory as a power source, and quickly exhaust any memory energy that is there. Or, so I have been told...
SMOG tests are a PITA. My Ranger could not pass when new in Dublin, and I had to go to a referee. More PITA, and time off from work on my dime. This after paying for the test fee, and then over $100 for another re-test at the Ford Dealer -they would not accept SMOG Station's failure report - and more to clean out the intake manifold.
The DIS module itself does not wear in any sense, as spark plugs or distributor rotors do. If it gets enough backfeed[back EMF?] from coils that cannot fire a bad plug, or similar, it can be damaged, just as a coil can get burned from arcing when it tries to fire a plug and has no where to go.
I think the silicon di-electric grease would perform just as well as the heat sink compound, or at least well enough, as it is supplied with the DIS modules and the GM HEI modules, to be applied to the 'back side' of the modules where they mount on/in the distributor body.
tom

 

Thanks for all your comments. I really appreciate the help. I'm mostly an old truck guy. This is my only "modern" truck and really its been a terrific work horse. I bought it new and its the only new car I ever bought. I use to drag race it at Infinion Raceway in the late 90's etc with traction slapper bars/4:11 gears with limited slip diff/drag radials/elect fan/smaller front pulleys/a modded computer chip/elect fan/ and on and on. I even had the motor blue printed by a local shop who specialized in drag racing motors etc. I raced in the SportStreet class against other 4 and 6 cylinder cars. I had a lot of fun and did pretty well with it. As a long bed its 300lbs heavier than the short and a lot heavier than many other sport street type cars but it was really quick. I pretty much always beat the 6cylinder Rangers--I really liked that--lol. Just because they hadn't done the extra things I was doing. If they had of course they would have been quicker than me. I was about 17.35 sec in the quarter. Slow in general, but winning is winning and they use a handicap type start so anyone could win.

This has been a great truck. At the same time I used it daily in my cleaning business. I'd just take off the ladder rack-put on the drag radials-and go racing. I was "low $" racing and I really like it. Now I've got a 460/58F100 pro street truck that I race--occassionally--not often like the Ranger. Not so interested in racing. But like to restore/build etc.

The smog thing here can really be crazy. I always passed the "tail pipe" emission tests with my Ranger--I never changed the camshaft profile etc--and the computer chip I just used at the races etc-I'd take it out for regular use-and they used to overlook some of my mods like the electric fan etc and underdrive pulleys, but now that's also a problem-Same with the special MAF air intake thingee I used to use. Everything is subject to a visual check. Its amazing how complicated they've made it here. They just don't want anyone "touching" the factory setup--even if it improved the polllution output etc. Its all kinda wierd. I believe I've totally returned everything to OEM.

My other trucks are not subject to smog checks, because currently in Calif vehicles over 25 year old are exempt. Does that make any sense? No not really lol. I guess its all about special interest groups and such. Its hard to make any sense out of it. But in other words its fine that I drive my old 48F1 with the 312Yblock, the 58F100 with the 460, or my 48IH with a 350, and of course these are all carburated with none computer non smog etc. Go figure??? But of course I don't drive these things much. Just special situations mostly.

I don't know what the future holds. Maybe someday they'll clamp down on the old trucks too. I hope they give us something like minimum use or so many gallons a year, because yes they dont' run as clean, but I'm not a commuter. I don't consume many gallons of gas per year.

Really appreciate all the help at Ford-trucks.com.

Good luck Tom