Couple of question about the infamous tranny module...

1. ) What are the most common symptoms?
2. ) Exactly how difficult is it to replace?
3. ) If it is bad, and the engine is drawing in ATF, what does this smell like? (Never smelled burned off ATF before) Would it make the van smell like it's running really rich? Whould it produce any smoke at all?

I ask because yesterday, my wife's van started again - the antifreeze smell wasn't there this time, like it always has been in the past, but the van smelled like it was running super rich, but NO smoke. The van has new Motorcraft Platinum plugs and new wires on it's 4.0. As she was driving to work, it was not shifting right, and on two slight inclines, it stumbled real bad, and refused to move at all. This repeated this morning, when she got home, so I checked the fluid level...and with the van hot, and idling, after she drove it home, and shifted through all gears, the level was between the two holes in the end of the stick - no where near the crosshatches. The van is not leaving puddles, or anything, and this is the first tiem it has done this, and the first time it has shown to be low on fluid - she insists on having her oil changed, rather than saving money, and doing it in the driveway - last time was 1 month ago, and they checked all her fluids, and were fine then...

Does this sound like the module has gone out?

Also, on a side note, after changing plugs and wires, the van has been running A LOT better, and actually has SOME pull to it. However, after checking, I found out it's got the 3.27 open diff...so it'll have virtually no grunt anyway...also sucks, if she ever wants to tow anything...

 

Sounds exactly like a modulator could have gone out. It is a maintenance item, so if you replace it, and it doesn't fix the problem, your money isn't wasted.

 

Pull the vacuum line off the module. There should NOT be any tranny fluid there. If there is then replace it. This diaphram leaking is pretty much the only thing that goes bad on the modulator. You can adjust them to change the shifting presure, but if you have not been adjusting this then don't is my advise. When you do change out the modulator the adustment on the new one may be different and you will notice the difference in the shifting.

 

Thanks...After all that I read, I was suspecting this as the primary cause...

One thing, though - as asked before, if the engine is ingesting ATF, will it make the van exhaust smell like it's running rich?

 

No not really, it just pings like mad when the engine is under load. Also, if that's really the case, an oil change is also in order.

 

If what is really the case? a bad mod? she just had the oil changed...like 2 weeks before all this started...which was just 3 days ago...

 

I meant if you are really sucking tranny fluid into the engine due to a bad modulator. There was a post here a while back by someone noting that he gained one or two quarts of oil in his oil pan, all the while loosing that much in the transmission without any noticeable leak. If this happens only recently and she just changed the oil, you should be OK.

 

Good...and I plan to replace the mod this weekend...

 

Also check the speedometer module because it will cause stalling, bad shifting and very bad gas mileage.