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manual and auto idle control valves - interchangeable?

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I need a IAC for my 90 2.2 manual .

A fellow USMB user has one but its for a Auto trans.

The only physical diff. is that the auto IAC has 3 prongs on it and the manual has only 2.

Are they interchangeable?

There is an article about that in Endwrench. It says Hitachi and JECS IAC valves are not interchangeable.

  • Author

I believe mine is hitachi.

So this means that Hitachi is the manual IAC and JECS is the auto IAC.

Correct?

I did an engine swap from a manual to an automatic earlier this year. Both cars were 91 models so I figured there should be no problem. Car ran like crap (No starting cold with out foot on accelator, after warmed up it would idel on the stop screw thats not intented for that purpose. Any thing below 1K RPMs it ran on 2 cylinders. A major slug NO POWER) until I learned that the IAC and fuel injectors are different on the early model Legacy's between auto and standards.

 

There was a physical difference in the two that I have. The body of the standard IAC was much thicker than the auto one and one of the vaccum hose's came out at a different angle. Had to use the bolts that were on the auto unit as the manual one's were way to long and the longer hose from the auto.

 

Changed the IAC and throttle body out and it runs great now. I still have the one form the standard motor.

 

Hope this is helpful, Stumpy

If the two IACs are different, then one is Hitachi and the other JECS. It's true that Hitachi was used with manual transmissions and JECS with auto.

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