93 Explorer V6 not shifting out of first after recent repairs

[thephilosopher]

Howdy

I have a 1993 Ford Explorer (I think its a sport) with 110,000 miles on it. I've had very little work done to it, mostly brake work, some front end work and a tune up at 60k miles. Although the lots of little things have been going wrong with it, the engine has held up well. I had some clicking while accelerating for a long time now but no other problems

Recently I began having a stalling problem. While idling in park or sitting at a light, the engine would often stall. It would be idling fine and then just stall, or seem to fight it for a second and then stall. I drove it as it was for about a month, just making sure to give it a little gas while idling (usually holding about 1k RPMs) and it never stalled.

Finally I go to get it fixed and the mechanic says its a fuel pump. They replace that and when I get it back its stalling worse than ever when I start it and it won't shift out of first. They look at it again and see a gasket was pulled into the intake manifold. They fix that, and the stalling problem is now gone but the truck does not shift out of first until about 3.7k to 4k RPMs. Once it shifts into first it seems to shift fine although it runs on the high RPM side. It never did this before, nor did I have any shifting problems before the fuel pump or gasket work.

After some browsing I've considered that it could be a stuck governer. Also read something about the TPS affecting this.

After the repairs its in worse shape than when I brought it in. A couple questions.

1) What is the TPS? How does this affect shifting?

2) Could any of the repairs or a failing fuel pump I drove with for a month cause this high shift problem? The mechanic mentioned the computer might have to relearn the shifting, but I rarely if ever got my truck up to 3.5k RPMs before.

3) Any ideas as to another causes I should look into.

As you might garner, I am by no means a car expert. Changing the alternator on an earlier car of mine is about as far as I've gone.

Thanks for your help.

The Philosopher

 

[JDraper]

1. TPS is the throttle position sensor. It tells the computer how much you have opened the throttle. This can affect the shift point.

2. The computer may have to "re-learn" your driving habits, but it's not going to be drastically different than before. Does the truck shift below 3500 under very light throttle, or does it always shift there? I don't think you probably had a failing fuel pump. Sounds more like it was just the intake gaskets, which is a common issue.

3. You might want to make sure that the vacuum modulator on the transmission is A) Hooked up (this could cause funky shifting and a high idle as it being disconnected causes a vacuum leak) and B) In good working order. Usually you can tell if it's damaged if there is tranny fluid in the vacuum line going to the modulator. The vacuum modulator is located on the passenger's side of the vehicle underneath the transmission heat shield.

I'd suggest you purchase a Haynes repair manual for the Explorer. They are easy to read, have a lot of good data/info and cost under $20.


Oh, BTW, Welcome to the Site!!!!!

 

[thephilosopher]

Thanks for the reply JDraper

The shifting is drastically different than before. It would always shift before or by 3,000 RPMs, even when I was heavy on the throttle. I will have to try it under a light throttle to see if that makes a difference, but letting off the gas slightly to force it to shift was not working.

I was suspicious that it was not the fuel pump myself. I think you are correct and that it was the gasket all along. It seems to match the symptoms the truck had.

I'm going in search of the Haynes manual and will use that for some additional reference.

The site has a lot of good information, and I wish I had come here before I went to get repairs. Keep up the good work.

Thanks for the excellent information you gave me, it will be very helpful as I try to resolve this.