New Member Learning...missyt

[missyt]

Missyt here...new member...so glad to have found this site. Have a treasured 94 EB...but for 3 years now, so far unsolved problem. Whenever vehicle sits in the sun or idles for any length of time (esp when AC on), the transmission jumps from gear to gear...once on the road, with air moving thru it does not do that.

We have had the most obvious sensors changed and still does the same. Someone has said that there is a sensor on top, right under the hood (that would

explain why the heat from merely the sun would affect it).

Hopefully some one of you will have had this experience and can tell me definitively what the problem could be and if indeed this sensor exists...I obviously do not have the right mechanics in my vicinity and am tired of paying for their guessing games...am also tired of not being able to drive my bronco for fear of damaging the transmission...

Please and thank you in advance for any help you guys can give me...

 

[Justshootme84]

Howdy & Welcome to Bronco Zone!!!

Your 94 Bronco has numerous engine sensors and everything is controlled by the ECM or computer, including the shifting of the transmission. It sounds like the tranny is overheating, causing it to search for gears. CHeck the fluid on the dipstick for any burnt smell or dark color. It should be light red/pink. The fluid is cooled inside the radiator, and you might also have a separate cooler in front of the radiator. Be sure these are not plugged up. Also check the fan clutch, as it may not be working properly. If any of the engine sensors are bad, they should put up a code that can be read off of the ECM. Good luck and post up any updates!

 

[Ktomek06]

Welcome to Bronco Zone, Be sure to take some pics and make a gallery when you can!

 

[missyt]

Missyt here...trying to find my way around this site...if I am not doing it right...someone tell me...please and thank you.

Thanks for the welcome and reply from admin...am hoping someone may log on that has had a similar experience and will reply as we have done all the obvious.

Am glad to have discovered this group as we are a 'house of trucks'...4 broncos, '86, '89, '92 & '94...all running with teenagers loving them...and friends with broncos as well...my front yard has become a parking lot...it's a good thing I love my men and their trucks... will add pictures as soon as I have time to figure out all the controls for this site... /emoticons/[email protected] 2x" width="20" height="20" />

 

[4xfan78]

For a quicker response to a problem look down from where you made this post and put it in the 80 and up catagory. As far as the shifting problem I had the same problem on one of my trucks I found that it was a vaccum controld diaghfram ( sorry cannot spell today, also cannot remember what it's called) on the driverside of the trans. it should be the only thing that has a vaccum line on it.

 

[Justshootme84]

Good point, that should be the modulator. My experience has been that I have to go to 3 or 4 shops to get an estimate when it comes to transmission work. The E4OD that you have also has shift sensors that tell it when to shift. 3 shops will want you to rebuild it, but the fourth will tell you which sensor is bad. Sometimes, metal filings will collect on the inside of the sensor and cause it to malfunction. Since I have seen folks pay up to $3000 to rebuild that model of transmission and a sensor is less than $100, I would keep looking for a good shop.

 

[walkdawg]

Welcome to the zone!!

 

[Guest_missyt]

Thanks everybody...

I went on a mission myself...much to my guys' surprise...got manuals, print outs of the top portion of the engine, that could be affected by heat from the sun...come to find out, only the diesel engines were issued with a heat shield on the under side of the hood...as mine is gas and black as well...it had to be close to the top...

Lucked up on a young employee of a transmission shop, mud-racer, that was willing to shade tree it, altho there was no shade and in his driveway in 95 degrees, he sweated thru a process of elimination with me for $30 and a cold beer...

We isolated it to the one sensor right under the accelerator and transmission linkage, the only one close under the hood...wrapped it in some insulation and am driving it without problems...so obviously that was the source of excess heat...the sensor appears ok, so will insulate it all properly after we are sure (it has been raining and will wait for a day of hot sun to make real sure), however, I am convinced that is it...

After 2 years of needless repairs and replacements of everything down under and around the transmission...I wish I had all that money back to give to the young mud racer, who was the only one willing to really think about it with me...to everyone else's defense, the electronic computer checks showed no problems everytime we had it checked...just goes to show you, sometimes you have to use the brain God gave us /emoticons/[email protected] 2x" width="20" height="20" /> and educate yourself...scarey to think about the doctors we never question !!

Thanks again...soon as it stops raining will get pictures in place... and may be posting one of these broncos for sale as college bound boys are thinking of girls and vehicles more conducive to dating... never would have believed that a couple of years ago !!

 

[Justshootme84]

That's great news!!! Let us know what that sensor is called, if it's the TPS (throttle position sensor) or whatever. Sometimes the best mechanics are paid in "exchange" (i.e., beer) rather than dollars!!! A girl friend of mine has an 88 black Bronco and I'll tell her about the troubles you used to have. Happy wheeling, and don't forget to remove the factory hardtop this Summer!!!

 

[Broncoholics]

If I were you I'd get an external tranny cooler with a built on fan and a gauge in the cab so you can monitor the heat. This helped mine big time! So did the engine oil cooler...