Engine Control COmputer Programming

[mr_master]

Hi. I own a Ford Explorer 1996, 4x4. I purchased a Engine Control Computer, I researched a little bit, and it turnes out that the new computer did not have the same serial number as the one it came when it was newly purchased but rather a compatible one(newer model I guess). The old computer was damaged. The problem is that the vehicle has a constant problem now, it trebles and the revs go up and down on iddle. Even, when I drive long distances, the revs goo all the way down to zero and the engine dies. That is very dangerous so my Explorer is now parked and I can't use it. A mechanic told me that i needed to "reprogram" or "reset" the computer and that he would do it for a fee. That sounded fishy... I changed almost all the sensors, and it does the same. Even a the computer diagnostic says that it works ok(even when the vehicle is trembling!!).
Please, any insight is well appreciated. tanks in advance

[UncleBob]

really, what you need is someone that knows what they are doing to look at it.

Off the cuff, a common problem for fords is dirty IAC's and it can cause the idle to hunt or the engine to stall. But the "trembling" you describe, might be a misfire. Hard to say from here.

[mr_master]

Originally Posted by UncleBob

really, what you need is someone that knows what they are doing to look at it.

Off the cuff, a common problem for fords is dirty IAC's and it can cause the idle to hunt or the engine to stall. But the "trembling" you describe, might be a misfire. Hard to say from here.

Thanks, Actually I have replaced the IAC valve twice. I also changed the 4 oxygen sensors, the EGR valve(the one that looks like a UFO).
Also, when the engine is trembling I unplug the EGR hoose, and the revs go up and it stops trembling, then I plug it again and it strts trembling again and all of a sudden, it stops trembling again, then I unplug the hoose again and the hoose vacuums(sucks)only but a little bit of air. And then it starts failing again(revs go up and down).
EDIT: I have noted, also that I unplug the TPC Sensor, and nothing happens. I unplugged the TPC on my mustang and the engine feels it unlike the explorer, the unplugging of the TPC has no repercussion on the engine.
I'm starting to think that I need a priest instead of a mechanic hahaha

[UncleBob]

Originally Posted by mr_master

Thanks, Actually I have replaced the IAC valve twice. I also changed the 4 oxygen sensors, the EGR valve(the one that looks like a UFO).
Also, when the engine is trembling I unplug the EGR hoose, and the revs go up and it stops trembling, then I plug it again and it strts trembling again and all of a sudden, it stops trembling again, then I unplug the hoose again and the hoose vacuums(sucks)only but a little bit of air. And then it starts failing again(revs go up and down).
EDIT: I have noted, also that I unplug the TPC Sensor, and nothing happens. I unplugged the TPC on my mustang and the engine feels it unlike the explorer, the unplugging of the TPC has no repercussion on the engine.
I'm starting to think that I need a priest instead of a mechanic hahaha

if connecting the EGR makes a difference, then that is a clear indication that its not working properly