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UPDATE: Idle Speed Problem

  • Thread starter Thread starter mo_dingo
  • Start date Start date Dec 31, 2003
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mo_dingo

20+ Year Stangneter
Aug 26, 2003
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Tucson, AZ
Jan 2, 2004
#21
  • Jan 2, 2004
  • #21
Well, after disconnecting the battery, and driving it for a while, my CEL light came on for a second or 2. So, I will run the codes tonight.

Talked to a "ford nut" mechanic, and he said that the TPS cannot handle carb cleaner. I might have messed that up, seeing as I sprayed most of a can of carb cleaner into the TB. So, if the code spits out a TPS code, it's going to get replaced tonight. For 33.99, it's definately worth it.
Scott
 

Slow5.0

Active Member
Feb 13, 2003
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Portland, OR
Jan 2, 2004
#22
  • Jan 2, 2004
  • #22
I have this problem too about 7 months never fixed yet
 

mo_dingo

20+ Year Stangneter
Aug 26, 2003
3,031
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Tucson, AZ
Jan 2, 2004
#23
  • Jan 2, 2004
  • #23
Really???? It irritates me too much to let it go that long!!! You must have some patience!!!!

I will post back in a few hours. I can't let the girls see my car like this, so it's getting fixed soon!!!
Scott
 

Slow5.0

Active Member
Feb 13, 2003
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Portland, OR
Jan 2, 2004
#24
  • Jan 2, 2004
  • #24
I have 5 or more post here on Stangnet about idle , I think my idle is fine(must be like that)
Problem is , rpms going down too slow from 1600 take 7 sec after reving up
 

mo_dingo

20+ Year Stangneter
Aug 26, 2003
3,031
2
58
Tucson, AZ
Jan 3, 2004
#25
  • Jan 3, 2004
  • #25
Seth5.0 said:
I have 5 or more post here on Stangnet about idle , I think my idle is fine(must be like that)
Problem is , rpms going down too slow from 1600 take 7 sec after reving up
Click to expand...

That sounds like you IAC valve. Is it the stock one? How many miles do you have. Does idle speed return to normal after 7 seconds?

Alright, back to my dilemma. I ran the codes and got a 124, 411, 412.

124=TPS Voltage higher than expected.
411=Unable to control RPM during LOW RPM self test.
412=Unable to control RPM during HIGH RPM self test.

411 and 412 were expected. 124 was not.

So, I figured I toasted my TPS. I had to special order my TPS which I received today. I installed it, restarted the computer, and guess what???

PROBLEM STILL NOT SOLVED????

How the hell could the TPS be reading an incorrect voltage when it's brand new, and the butterfly valve it closed at idle speeds??????

I am so confused!!!!!!

Could I have installed the TPS incorrectly? I did remove the TPS originally, but did nothing with it. When I put the TPS back on (both times), I didn't line up perfectly. The TPS is spring loaded, so it needed to turned slightly so the bolt holes would line up. Is this wrong?
Scott
 

mo_dingo

20+ Year Stangneter
Aug 26, 2003
3,031
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58
Tucson, AZ
Jan 3, 2004
#26
  • Jan 3, 2004
  • #26
Oh, and I figured out a way to fix the problem temporarily.

If I punch it in 1st gear (WOT), all the way to 5600, then let off of the throttle, my idle speed will return to normal. Sometimes, during acceleration, it will suddenly return to bad idle, but all I have to do is punch it again in 1st and problem solved.

Also, I can turn my car off (while idle is normal), start it back up, and the problem starts again.

BTW, my CEL light comes on while driving. It's spitting out the same code, 124. The CEL light will stay on for at least 5 minutes, then all of the sudden, go off. Also, the CEL light is on when idle speed is normal, not when idle is bad. It usually takes a bit to come on. I think about 15 minutes after I disconnect the battery and the PCM has time to figure out what's wrong.
Scott
 

Slow5.0

Active Member
Feb 13, 2003
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Portland, OR
Jan 3, 2004
#27
  • Jan 3, 2004
  • #27
I try two new idles , everything is same so idle air control is good
 
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