Driving my '97 Explorer V6 SOHC auto 4x4 (64K miles) on a 400 mile round trip in hilly country, I pushed down the accelerator when pulling past a vehicle as we climbed an incline. The turbo kicked in, not as cleanly as normal and the check gauge light (red) flashed on momentarily. Further on down the road, I noticed the engine temperature gauge was above the normal midway position and was creeping towards the top. I dropped engine speed and cruised at 58 mph for about 25 miles (rpm 2000 thereabouts), it helped cool it off but needle stayed above mid position. Came to a toll bridge where roadworks were causing 60 minute delays and had to pull up with the delayed traffic. I slipped the truck into neutral and noticed the rpm rise to 2100, it would drop to 1500 when crawling forward in Drive, as the traffic moved bit by bit. It always rose back to 2100 when in neutral and had a racing sound. Has anyone experienced this sort of problem, is it a transmission problem, or could there be other problems with the engine? Overnight the problem seems to have disappeared, but I have yet to take it out for a long drive.

 

Well, here's my five cents, if it helps. One friend of mine experienced the similar problem on I-generation Explorer (92 Eddie, 4.0L OHV, A4LD automatic transmission). Though idle speed was normal, engine was overheating all the time and shifting was somewhat strange.

The reason was automatic transmission fault. As I understand, the main radiator has an additional circle for cooling automatic transmission fluid. So, if ATF is being overheated, engine might experience overheating as well. Also, overheating affects automatic transmission's behavior and obviously reduces its life. If tranny is being constantly overheated, it obviously needs a repair as soon as possible.

You might want to check if my conclusion is correct, and you have a trouble with a tranny. First of all, pull out the ATF probing rod and try to smell at it. If ATF smells burnt (not warm, but burnt) -- you're in trouble. Also you should note that normal operating temperature for A/T is about 90° C / 190° F. If ATF after the trip is hotter than this, that's bad.

Then, if ATF color is not red, but brown (or worse, is black) -- this also is not good.

That's all I can say regarding this problem. Hope this helps a bit, and also my guess is not the right pick.

With best regards,
Yuri

 

Yuri
Thanks for the starting points - I went out and checked what I take to be the Transmission stick. No burnt smell and the oil looked pink rather than red, which I take to be a healthy sign. Took the vehicle out for a four mile run and it behaved perfectly. I'll keep an eye on this problem and hold back on the kick-down turbo charge for a while!
Donald

 

Don, most of these newer computer controlled engines have sensors in them which will "step up" the idle speed when the engine is running hot. The computer is just trying to circulate more coolant to get the engine to cool down. Ford coolant thermostats are notorious for failing. Check your coolant level and if it happens again I think I'd replace the thermostat. .....best of luck.......mike

 

Mike
Thanks for that advice. I did go out yesterday morning and checked the coolant in the radiator, in fact as I undid the cap some spilt out because it was so full. The reservoir was also above the full level. I'll definitely replace the thermostat this summer (or earlier) as I am sure they will tend to fail beyond 60K miles. By the way, I also checked for any codes, none there.
Donald