IAC or transmission or ??????

[bswoboda]

I have a 2000 Explorer XLT with about 72K miles on it and absolutely no problems until Saturday. I was coming back to LA from San Francisco and cruising down the highway without any problem until I get into the outskirts of LA. As traffic slowed us down to a stand-still, the engine shuddered and died. I could start it up no problem but once I shifted into drive, it would die (this is pretty bad on an LA freeway).

I finally figured out that once I started it (and it worked fine in P, R, and N) if I shifted it to first gear manually (i.e. 1), it would run fine. I would drive in 1 and then manually shift into 2 and, as I picked up speed, I could then shift it into D without any problem.

Once I got home, I tried holding my foot on the brake, shifting it into D and getting the RPMs up there to stop the stalling but it sounded (and felt) like there was no power there (kind of a low hum instead of a racing engine).

I cleaned the IAC valve but it didn't make a difference. I did the Ohm test and it resistance between the two connectors on the valve read about 1 Ohm. I went to the dealer, got a new IAC and tested that one before I paid for it and I got the same reading (I'm obviously doing something wrong in the testing). The parts guy said that the best thing would be to just give it to the service dept. and have them run a diagnostic to determine what's up.

I just talked to the service department and they said that the computer came up with the code that said there was something wrong internally (I'm trying to get the actual code from them and will post it once they call me back - yeah, don't hold your breath). They said that it was either the torque converter or the main control and it would cost $1,400 in labor and whatever parts they needed to fix it. He tried to explain to me that the reason it's the torque converter is because putting it in D uses a different low gear than manually putting it in 1 (he actually said it was a lower low gear than 1). It sounded like a bunch of bullshit to me and I wasn't buying it. I told him not to do any work on it and I would get a second opinion.

Any thoughts out there as to what the real problem might be? I haven't had any transmission problems (except a few thunks when I quickly shift from R to D). I also thought it was weird that this problem would happen at the end of a trip while I was driving without any other symptoms.

Any input is much appreciated.

Thanks.

-Bryan

 

[Alec]

What? D uses a different first gear than 1? Ford should fire that guy.

It definately could be the tranny, but I'd try the IAC first.

 

[bswoboda]

UPDATE

The codes that were returned are: P1506 and P1507.

A buddy of mine recommended that I go talk to a mechanic friend of his who runs a service shop in El Segundo. I explained everything to him and he immediately guessed that it was the torque converter. He went on to say that Ford and GM have known about this problem for a long time and that they keep discussing this point. Apparently they are cutting corners to keep manufacturing costs down and passing the burden onto the consumers. He also said that $1,400 labor for this job is actually cheap and that parts and labor would run me about $1,800 - $2,000 and that's a good price.

He said that there's also an issue with the cooling systems on these cars. The radiator fluid should be completely flushed every two years along with the transmission fluid to help avoid these problems.

Don't get me wrong, I love my Explorer and have taken it to all kinds of weird and tough places but this just sucks and apparently it's a US-manufacturer problem. Toyota's and Honda's don't have this kind of problem.

I just report it as I hear it. I'd love to hear everyone else's comments and experiences.

 

[Alec]

Yes, coolant and tranny fluid should be changed every 15-20k miles. Coolant is ok every 30k if monitored.

You should also have an aux tranny cooler installed.

My 4R55E rebuild cost 2400 with almost all new parts, labor, 2 year warranty. Thats on the high side.

Sorry man, good luck!

 

[huskyfan23]

eBay has rebuilt 4R55E trannys with warranties for under $1000.

 

[cjbarron5]

hold the phone have you looked up these codes ford gave you? if not you might want to thay both refer to the iac and say nothing about the tranny i would change the iac first and see what happens as far as the bs about diffrent gears in 1st it is exactly that bullshi@@@

 

[Glacier991]

Actually, 1st IS created differently in OD (Drive) as opposed to in Manual 1st gear. In Manual 1st gear Overdrive clutch is applied. In OD 1st it is not. In manual 1st the low/reverse band is applied. IN OD 1st it is not. There IS a difference.

regardless, the IAC issue needs to be addressed first. If that doesn't solve it,
read up on a the function of the TCC Solenoid. If the Torque Convertor Clutch will not disengage,the engine will never be completely disengaged from the wheels/road and when you stop, so will it. I'd want to know the actual transmission code read (If there was one - and not just the engine code for the IAC). You may not need a complete rebuild.

 

[dogfriend]

I cleaned the IAC valve but it didn't make a difference. I did the Ohm test and it resistance between the two connectors on the valve read about 1 Ohm. I went to the dealer, got a new IAC and tested that one before I paid for it and I got the same reading (I'm obviously doing something wrong in the testing). The parts guy said that the best thing would be to just give it to the service dept. and have them run a diagnostic to determine what's up.



Any input is much appreciated.

Thanks.

-Bryan

You should check the resistance of the IAC again, make sure to observe the correct polarity because there is a diode in the circuit . VPWR is usually a red wire.

 

[cjbarron5]

thank you glacier991 i had forgotten about the application diffrence for 1st gear
i stand corrected