95 3.8L Ignition problem.

Hello everyone.

My 95, 3.8L, 157K MILES, is suffering from what I first suspected to be a transmission problem. . . But . . . having had my transmission serviced, now seems to be an ignition problem. At idle, the engine, when warmed up, in gear (D), warbles. Steadily wavers from 750 rpm down to 600, but never quits. Transmission guy says this is an ignition "miss". I have changed my coil pack, wires and plugs within the past 20k miles. I will replace them all again now, and post results. Unless one of you has experienced this problem has a unique solution.

Karl.

What happens when an ignition control module goes bad? It's very expensive, $177, so this is probably my problem.

Karl

I would think that you would get a code(s) if the Module was defective. A common cause of idle problems is the IAC (Idle Air Control). When your foot is NOT on the accelerator.....the IAC is what controls the air into the engine.

One thing that you can try, is pressing your foot on the accelerator just enough to very slightly speed up the engine.....and see if it still hunts. If it does...most likely the problem is not the IAC.

Another possibility is if there is a problem with the Throttle Position Sensor (TPS)...less likely.

Yet Another thing to try is cleaning the MAF (I have detailed pictures of the MAF on the '96 3.8L in my pictures). You hold the MAF so that the hole that faces the air filter is facing UP.....and the rest of the plastic bar that that hole is on....slopes down away from the hole...spray non-residue electronic cleaner in the hole that faces the air cleaner.....and it will run out the hole that is on the other side of the bar....flushing out any crud.

An off the wall thing to try...if none of these work.....is to look into the fuel pressure. The fuel pressure regulator has a vaccum connection on it.....and the fuel pressure will vary with a varience in vaccum. More vaccum = less fuel pressure. The idea is to give more fuel pressure under heavy acceleration (which results in lower vaccum). I remember reading something about the vaccum connection becoming loose and causing a vaccum leak at that point. I thought it was on newer windstars.....but...worth a look. The Fuel Pressure regulator is on the fuel rail......on the '96....it is on the passenger side...very near the IMRC actuators..... I am not sure where it is on the '95...... as you have a different intake manifold.

Thank you Wiswind.

This problem is barely noticable. It is intermittent. I now realize that for the past year the car "sometimes" didn't start right. Also, at a stoplight, the car "sometimes" does the idle warbling thing. And now that I'm keen on this problem, notice that at idle in neutral, the engine "sometimes" misses. I can't feel it, but I can hear it, and when I stare at the tach, I see it. Also, up in the hills, very rare for us flatlanders, the transmission, I assumed, "sometimes" fouled up when downshifting. But now I think all these symptoms are related. You're driving me toward a fuel solution. I go there next. I've done this so far.

1. Replaced the wires. Former set was Borg new set is Aaction store brand. Drove it . . no change.

2. Swapped out 1-2-3 plugs Former set was Autolite, current set Autolight. Drove it . . No change.

3. Swapped out 4-5-6 plugs. No change.

4. Pulled all harness connection to coil pack and ignition module. Used my trusty dental pick & contact cleaner to clean and slightly bend each pin connection. Wife drove it, and said "It's fixed" Now, I don't believe her yet. This problem comes and goes. (as in, "lately the car behaves like #$%^!", or "for two weeks the car has behaved fine". We might just be getting into a good phase. However. Tomorrow I'm driving the car for 8 straight hours to get to Smoky Mtns NP. That'll be a sure test. I'm currently installing the trans cooler. will check in later, then in the morning, then I'm gone till Tues evening.

Wish me luck.

Karl

Good luck on trip!

You may have gasoline filter changing in your near future. The pump screen in the tank ... and the in-line in the tubing. Its the one in the tank that may be affecting you most. And at your years and mileage (your Winny, not you) you probably should replace the pump just to get new internal valves.

Hello friends.

I made it.

12Oz, the fuel system is clean. I suspected it first, and went into the tank this time last year. I swapped out the sending unit, the pump, the big filter. Then I posted for the first time here.

I didn't get a chance to install the trans cooler. I spent 7 hrs getting to destination with my fingers crossed, and my smiling promise to my wife that " It'ss fixed"! Then, When we were going West on Interstate 26, on the big steep hill at S/N Carolina line, the transmission hesitated/shuddered. Here's what happened, as my wife put's it, (in a phone conversation I overheard) . . ". then the car started bucking, so, I floored it! Ha Ha, the thing spit out a hairball and . . . took off like a bat outta hell! . yeah . . that fixed it!" Golly these southerners have a way with words. Truely the car hasn't shown any transmission issues since. BUT. The CEL light came on when she floored it. and the hesitation issue at idle was still present at our destination. Code read out P0340. Cam Position sensor out of sorts. I had it cleared. Then I slightly bent all the pins on the connection to the coil pack. Guess what? The idle hesitation disappeared. And no new codes have surfaced.

Glad to be home

Karl

Tranny cooler lines, take a look down behind the driver side headlight.....next to the ABS module....you should have a clear shot......And then I was able to squeeze through to in front of the radiator. I removed the plastic trim panel that is above the top front of the radiator.....to work with the cooler / fluid lines. I had 1 sharp edged sheet metal point...that I cut a piece of plastic door edge molding....and slid it over....to prevent the hoses from being cut. Elsewhere....I slid some plastic covering over the hoses...in my pictures...it is light blue. My cooler is installed with the connectors facing UP....so the lines go down to it from above. I had to trim a corner off the plastic trim piece to get it to go back on. The whole system has been working great for over a year.

Hello everyone,

Intstalled the trans cooler. I was just about to cut throught the plastic on top of the radiator, as you suggested Wiswind, but then noticed the PSteering cooling tube coming around to the front of the radiator on the passenger side. I then noticed that the same gap existed on the drivers side, and this is the way the tubes to my cooler are routed. I cut my old top radiator hose through the band saw to create an anti chafing sleeve, and ran two hoses through it. I tied into the line the top rad fluid line. Biggest problem was pulling the fans back enough to shove the mounting clips through the radiator. The cooler is mounted vertically, with the entrance exit tubes facing down. It is directly in front of the drivers side radiator fan.

Thank you for all your help. Wiswind, the pictures are great. I must investigate posting a few. It sure helps to see the dark innards before you have to go there yourself.

Karl

I hear that on the fan assembly.....Step #1 in removing them....is to undo the ABS unit....which is in the way. I was....and still am afraid to touch that thing.....it is working great.....and it is an expensive thing to break.....

I'm sure that those out there who are much more the mechanic than I am find it funny that I am afraid of my ABS unit.....but....that is fine with me.

So I cut the heck out of my hands shoving them down in between the radiator and the fans......
That is why I have not posted detailed pictures of my Tranny cooler installation. I am happy with it....but I have slim hands....and was wishing that they were much more slim while doing the installation.

Here's the latest.

The engine idle "warble" and downshifting hesitation came back again. So in keeping with the scientific method I changed 1 thing at a time.

I rebuilt my broken 4 pin clip harness clip for the coil pack. Drove it to work and back. No Improvement.

I bought and swapped my 2 yr old coil pack (bought new), for an Advance auto (GP Sorensen, $60) coil pack.

Drove it . . .
Made a difference.

Drove my 10 yr old to summer camp, 600 miles round trip.

Ladies and gentlemen, the van behaved wonderfully. I did the trip up (to the mountains), 320 miles. No problems. My wife drove home, she agrees. It's fixed.

The sad thing is that two years ago I replaced plugs, wires and the pack, after the original pack failed. That incident was a clearly coded missfire cyl 4. I went and spent the extra money for superior products (OEM - dealer - motorcraft, plugs, wires & pack). And in all likelyhood is what brought on all my subsequent starter/flywheel, transmission, hesitation woes.

Now, the trans Cooler. Installing that cooler did nothing to change the position of the dashboard, coolant gauge. I was betting that the engine would run cooler, because the radiator would be unburdened with having to cool the trans fluid. Tie into the lower transmission line?