exploder idle issues

[Nathan123]

Well my 2.9 bronco ii was having most of these syptoms. I had a 1/4" thick aluminum adjuster plate between the IAC and intake. I took that out, put a new IAC on. Still didn't work right. So I cleaned the TB and found that someone messed with the idle speed set screw. It was backed so far off that it wasn't touching the lever on the cable. So i played with it till I got a reliable return to idle of around 850 (like the sticker says) when idling in park (when warm), and even just when coming to a stop. Not sure if the 4.0 has that screw set up though. It seems to me like the truck was compensating for running all gummed up and now that it's new again, it doesnt know what to do.

 

[dorramide7]

pull the codes and see it the tps is the problem or something else, I cleaned my MAF with vinegar and what a difference it made, no more hesitation.

Louis

This happened to me once. I dunno that it's your problem, but my issue was that my TB had been so gunked up for so long that the computer had learned to deal with it by opening the IAC further. I went and removed the gunk and the computer didn't adjust very well. I had to go and manually reset my idle speed.

 

[85ranger302]

is there any way the transmission or torque converter could affect the engine idle? cause i think my converter is clunking whenever i shut the motor off

 

[Nathan123]

You can always check the kickdown linkage to make sure its in adjustment.
http://www.therangerstation.com/forums/showthread.php?t=92780

WTF posted how the kickdown is adjusted.

 

[85ranger302]

ok so i swapped out the tps last month and i think its bad, cause i keep getting the "throtte position sensor below minimum voltage" code, so im gonna put a motorcraft tps back on it.

 

[AgPete139]

Gluck.