misfire on idle/ IAC problem?

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kidwired
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misfire on idle/ IAC problem?

Post by kidwired »

I've had a rough idle once the car is warm and the car (EJ22T) stalls at stops, the misfire clears as soon as I touch the throttle. Idles fine when cold.

I changed plugs (NGK vpower) tested plug wires and seafoamed the IAC.

Today I disconected the IAC harness while running cold and RPM's went up, when I reconnected the engine dies.

Does this sound like a bad IAC?
Goodbye my sweet, parting is such sweet sorrow....1993 BC6 , Saab IC, with xtras Hallman MBC, HKS FCD , wrx exaust.
Legacy777
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Post by Legacy777 »

not necessarily.....but it could be.

Do you have a laptop and a way to view what the IAC duty % is?
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
kidwired
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Post by kidwired »

no laptop, but might be able to borrow a Modus. What am I looking for?
Goodbye my sweet, parting is such sweet sorrow....1993 BC6 , Saab IC, with xtras Hallman MBC, HKS FCD , wrx exaust.
Legacy777
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Post by Legacy777 »

If you have a laptop, you should be able to run vikash's scan tool and look at the duty %.

Mainly you're looking to see what the IAC duty % is.

This thread gives info on what the various values should be.
http://bbs.legacycentral.org/viewtopic. ... =scan+tool

You however don't want to jump to conclusions that the IAC valve is bad just because the duty % is outside the specified range. Usually the IAC is just responding to what the ECU is telling it to do.
Josh

surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT

If you need to get a hold of me please email me rather then pm
subytech
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Post by subytech »

This does sound like your idle air motor to me but like Legacy777 said check it out first before you go buying expensive stuff.
92 Legacy Turbo, 5sp MT, Early Large CC 20G heads, Ported custom clocked td04, Cobb catted DP, Injen SS 3" exhaust, Turbosmart MBC @ 10psi, Apexi 20g intake, custom FMIC, Fidanza 11lb flywheel, stock 05 WRX clutch
georryan
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Post by georryan »

Did you ever figure out your idle issues?
91 Pearl White Sport Sedan
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