IAC Pissing me off now.

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cj91legss
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IAC Pissing me off now.

Post by cj91legss »

well I'm just about ready to throw this piece of shit away. I replaced my JDM IAC with a Non Turbo IAC, and now I constantly have a code. Maybe it needs calibrated? Maybe Josh has the destructions on his site?
91 L-TW Wagon with a full Swap -RIP
92 SS Prefaced, GD dash swapped, 22T/205 Hybrid 20 psi - BEAST!
93 SS Bone Stock Gone!
94 TW Bone Stock Gone!
91 SS 4EAT Sold!
98 LGT 4EAT
98 LGT Wagon 4EAT
lucas
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Re: IAC Pissing me off now.

Post by lucas »

dude had horrible problems with mine, turned out to be wiring problems still isn't fixed but has a good bandaid.
1993 legacy ss "Shela"
cj91legss
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Re: IAC Pissing me off now.

Post by cj91legss »

I replaced it
91 L-TW Wagon with a full Swap -RIP
92 SS Prefaced, GD dash swapped, 22T/205 Hybrid 20 psi - BEAST!
93 SS Bone Stock Gone!
94 TW Bone Stock Gone!
91 SS 4EAT Sold!
98 LGT 4EAT
98 LGT Wagon 4EAT
lucas
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Location: tacoma washington

Re: IAC Pissing me off now.

Post by lucas »

did you get a new one or different old one?
1993 legacy ss "Shela"
cj91legss
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Re: IAC Pissing me off now.

Post by cj91legss »

different old one. I don't know if the problem is completely gone tho. My CEL came on yesterday for a brief moment while i was stopped, went away as soon as i started to drive again.
91 L-TW Wagon with a full Swap -RIP
92 SS Prefaced, GD dash swapped, 22T/205 Hybrid 20 psi - BEAST!
93 SS Bone Stock Gone!
94 TW Bone Stock Gone!
91 SS 4EAT Sold!
98 LGT 4EAT
98 LGT Wagon 4EAT
lucas
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Joined: Tue Nov 27, 2007 2:43 am
Location: tacoma washington

Re: IAC Pissing me off now.

Post by lucas »

see mine does that randomly too, kinda retarded my car will start to run crappy then as soon as i drive off it goes away. Clown shoes man clown shoes
1993 legacy ss "Shela"
Legacy777
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Re: IAC Pissing me off now.

Post by Legacy777 »

I would suggest checking the coil resistance on the two IAC valves and see how they compare. There shouldn't be any difference, but maybe one of the IAC valve coils is bad.

The coils should be about 9 ohms. Instructions are here.

http://www.main.experiencetherave.com/s ... C_Diag.zip
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
cj91legss
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Re: IAC Pissing me off now.

Post by cj91legss »

I checked the resistance on the coils, the current IAC on my car one is 9 ohms and the other is 10 ohms. My 20G IAC both coils read 9 ohms. I'm going to re-install the 20G IAC. I also replaced the wires with new 18AWG shielded wire to the ecu from the IAC plug, Just the outside 2 wires tho, still haven't quite figured where I want to get power for the IAC at from under the dashboard. I want to get power from under the dash because the 3rd wire is already there in the new run of wire I just installed...

However, I'm still getting an idle issue at stop lights, so with the IAC replaced, wiring replaced, only one thing left to do... Find another SS ECU. I'm nowhere near ready to install my EMS, Nor do i have 450 to go rob tune :/
91 L-TW Wagon with a full Swap -RIP
92 SS Prefaced, GD dash swapped, 22T/205 Hybrid 20 psi - BEAST!
93 SS Bone Stock Gone!
94 TW Bone Stock Gone!
91 SS 4EAT Sold!
98 LGT 4EAT
98 LGT Wagon 4EAT
lucas
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Location: tacoma washington

Re: IAC Pissing me off now.

Post by lucas »

hmm I've had the same problems almost what does it do at idle when you stop sometimes?
1993 legacy ss "Shela"
cj91legss
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Re: IAC Pissing me off now.

Post by cj91legss »

Idle bounces pretty rough
91 L-TW Wagon with a full Swap -RIP
92 SS Prefaced, GD dash swapped, 22T/205 Hybrid 20 psi - BEAST!
93 SS Bone Stock Gone!
94 TW Bone Stock Gone!
91 SS 4EAT Sold!
98 LGT 4EAT
98 LGT Wagon 4EAT
macipusy
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Re: IAC Pissing me off now.

Post by macipusy »

The idle on these cars drove me crazy....until I went standalone ECU. Now I have zero problems and still use the stock IAC.

I came to a conclusion that modding the old Legacies with the stock ECU is like running Photoshop on a PC from 1991.
maciek puszynski

01 Impreza | v6 STi RA | 5mt | ej236t
93 Legacy Turbo | TW | 4eat | ej22t
16 WRX | 6mt | fa20
98 Legacy GT | wagon | 5mt | ej25d


2.36L Turbo - RSTi Build
cj91legss
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Re: IAC Pissing me off now.

Post by cj91legss »

Hahahaha, well played
91 L-TW Wagon with a full Swap -RIP
92 SS Prefaced, GD dash swapped, 22T/205 Hybrid 20 psi - BEAST!
93 SS Bone Stock Gone!
94 TW Bone Stock Gone!
91 SS 4EAT Sold!
98 LGT 4EAT
98 LGT Wagon 4EAT
Legacy777
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Re: IAC Pissing me off now.

Post by Legacy777 »

Try running a "test" wire directly from the battery to the center wire on the IAC valve. Maybe there is fluctuation in the power feeding the IAC that is causing your problem.

If not, I'd say you've done everything to rule out the IAC valve. Replacing the ECU will probably get rid of the code, and may help the idle, but I too agree the stock ECU doesn't do a good job for the idle in these cars.
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
Alphius
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Re: IAC Pissing me off now.

Post by Alphius »

My least favorite part of the stock calibration is the idle and return to idle behavior. I'm considering going standalone just for that! And also better boost control and wideband referenced fueling, but idle is a big part of it.
CAV3MAN227
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Re: IAC Pissing me off now.

Post by CAV3MAN227 »

-When I was having my IAC problems, turned out it was the ECU that was giving me the headaches all along. Put in another ECU and all was fine!

-Joe
-I'd rather loose by a mile because I built my own car, than win by an inch cause someone else built it for me. Your car, is your story, so don't let someone else write the book. ~Moog
cj91legss
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Re: IAC Pissing me off now.

Post by cj91legss »

Well I did what you said josh, hooked the middle wire to the battery and its still acting up. So I guess I will replace the ecu. Not right away but soon. Either way it sucks.
91 L-TW Wagon with a full Swap -RIP
92 SS Prefaced, GD dash swapped, 22T/205 Hybrid 20 psi - BEAST!
93 SS Bone Stock Gone!
94 TW Bone Stock Gone!
91 SS 4EAT Sold!
98 LGT 4EAT
98 LGT Wagon 4EAT
Legacy777
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Re: IAC Pissing me off now.

Post by Legacy777 »

Yeah that does suck. Another option, if you can find a member near you that would be willing to do this, try swapping their ECU into your car to see if it helps. That way you'll have a better idea whether a new ECU actually fixes the problem.
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
cj91legss
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Posts: 6322
Joined: Fri Jun 20, 2008 8:17 am
Location: Lakewood, Wa 98439
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Re: IAC Pissing me off now.

Post by cj91legss »

Ill make a thread in the parts shed. Can't imagine an EU being expensive since everyone is going rob tuned or standalone
91 L-TW Wagon with a full Swap -RIP
92 SS Prefaced, GD dash swapped, 22T/205 Hybrid 20 psi - BEAST!
93 SS Bone Stock Gone!
94 TW Bone Stock Gone!
91 SS 4EAT Sold!
98 LGT 4EAT
98 LGT Wagon 4EAT
91legacyawdturbo
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Location: arvada co

Re: IAC Pissing me off now.

Post by 91legacyawdturbo »

Try another ecu is what I would do, did that with joe (cav3man227) an it fixed his problems, I think Dave (doaomo) has a few ecu's for 50? I'll vouch for his parts since they have saved my a$$ mutiple times.
91 SS, v9 ej207 twin scroll swap, Gda wrx dash swap.
2002 wrx sport wagon
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