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my "check engine" light goes on after about 5 minutes of driving, and it stays on mostly......and the only code that came up was 81

the guy who dropped my motor in doesn't understand it, and me and Pathogen consider him the best at 2.3L and 5.0 around this area (but he doesn't go online)

please help with suggestions......pathogen said it might be a sensor on the lower intake (not the knock sensor...but could be)
Code 81 -
Thermatic Air Diverter (TAD or AM-2) solenoid circuit failure, or Electro-Drive fan circuit failure, or Intake Air Control (IAC) valve circuit failure, or Boost solenoid circuit failure
You don't have thermactor so that's out.
Does your passenger side cooling fan come on for a couple seconds each and everytime you start the engine. It should. If it doesn't
I'd start there. If it does then you should look at the two remaining choices. Do you have an after market boost control valve? Is the harness still plugged into the original BCS? If it isn't it will throw a code.

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NATO Member. it's not a vice, it's an obsession
"The nice thing about each new day is nobody ever used it before" Barnaby Jones
88 TC X 2, 86 SVO, mods list at
http://www.turbotbird.com/showroom/pd_88tc.htm

[This message has been edited by Pete D (edited 07-06-2002).]
yes my friend has a boost valve plugged on my car. i'm not familiar with all the terms yet, i only know what about the O2 sensor, EGR, and WGA.

the boost valve hose attaches to the turbo housing towards the bottom, and that hose connects to the actual valve, and then the hose goes up and plugs in at the top (i dont know the name, but a few other vacume hoses connect there also)

thanks for the help
The gillis valve is hooked up but the stock BCS is gone (not plugged in). Rule that one out.

ADD: Its probably the IAC. I forgot all about that. Idle racing on occasion too. We'll check that tonight.

[This message has been edited by **PathogeN** (edited 07-07-2002).]
Quote:Originally posted by **PathogeN**:
The gillis valve is hooked up but the stock BCS is gone (not plugged in). Rule that one out.

[This message has been edited by **PathogeN** (edited 07-07-2002).]

I hope you guys figure it out. I think that was Pete's point that if it isn't there and plugged in. it will throw a code
The IAC isn't the problem because we plugged in a brand new one and i still got the "check engine" light after 5 minutes of driving

i dont understand the part about passenger side fan, that Pete D said. Also, my boost valve goes like this: vacuum tree --> valve --> vacuum inlet on turbo
Quote:Originally posted by r3lic76:

i dont understand the part about passenger side fan, that Pete D said. Also, my boost valve goes like this: vacuum tree --> valve --> vacuum inlet on turbo

The point about the boos valve is that there was an electrical connentor that went to the solenoid, that cannot be connected to the after market valve. That is why it will send a code, because there is no reading from the connector. This however should not have anything to do with the check engine light.

As far as the fan, as pete said the fan on the pass. side should come on for a few seconds when you start the car. Just check that by direct observation.
Is the code 81 a KOER code? a KOEO current fault code or a continuous memory code?? If the CEL stays on and then goes off, there will for sure be a continuous memory code stored. Is that where the 81 is from?

It is IMPORTANT to explain exactly what part of the test the code came up in..... they often have different meanings in KORO, KOER, continuous memory.

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Jeff Korn

88 Turbo Coupe: Intake and exhaust mods, T3 turbo at 20 psi, forced air intercooler, water injection, bypass valve, Ranger roller cam, subframes, etc., etc.. // 86 Tbird 5.0 (original owner): intake, exhaust, valvetrain mods, 100 HP nitrous, ignition, gears, suspension, etc., etc.... // 91 Escort: Bone stock winter car // 00 Windstar (wifes vehicle)
code 81 comes up right when i start the test, which i think is memory code

i plugged the stock BCS back in and i still get a check engine light
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