I too have this error code. Im sure its the TB. Mine started giving the error when I installed the KB, which comes with a TB. It may be related to TP sensor voltage. I haven't tried to fix the problem yet.

 

have you noticed anything detrimental to your car's performance due to this being on?

 

This code is set when your idle is higher than what the pcm is trying to control it to. A few things can cause this. Stuck IAC valve, vacuum leak, shorted wiring for the valve. But, being that you installed a new TB and then got the code. The throttle body is probably cracked to far open, causing the idle to climb. The pcm then can't control that.

 

have you noticed anything detrimental to your car's performance due to this being on?

No, haven't noticed anything

 

This code is set when your idle is higher than what the pcm is trying to control it to. A few things can cause this. Stuck IAC valve, vacuum leak, shorted wiring for the valve. But, being that you installed a new TB and then got the code. The throttle body is probably cracked to far open, causing the idle to climb. The pcm then can't control that.

how much tolerance does the meter have re: the t/b being cracked too far open?

 

how much tolerance does the meter have re: the t/b being cracked too far open?

Get your car warm, then while at idle, disconnect the IAC valve electrical connector. Does the idle drop dramatically, or stall. It should. If it doesnt, then either your IAC valve is stuck open, you have a vacuum leak, or your throttle body is cracked to far open. Single blade throttle bodies have always been tricky to get right.

Being you have an Accufab, I would call them and see what they say. A heavier return spring could fix it, but without starting a throttle body war, I just recommend calling them for a fix.

 

nice -- George is gonna give me a ring. I like their customer service.

 

If the idle is much over 850 to 900, you'll get that error code. That usually seems to be the problem. Some guys can get away with 850, but most can't. The car wants to idle much lower, around 725 or so, but when it tries to and can't do it, it gives that code.
And an added spring can definitely help cure the problem, if you have adjusted the TPS correctly and still can't get it to idle satisfactorily.

Dana

 

If the idle is much over 850 to 900, you'll get that error code. That usually seems to be the problem. Some guys can get away with 850, but most can't. The car wants to idle much lower, around 725 or so, but when it tries to and can't do it, it gives that code.
And an added spring can definitely help cure the problem, if you have adjusted the TPS correctly and still can't get it to idle satisfactorily.

Dana

yeah, it does the ol' 2 second idle at 1100, and then drops to mid 800s ... I was just coming to a stop at a light, (and thusly going to idle) when it came on ...

 

no call back from Accufab yesterday.

 

I have the exact same problem. Did you ever find a solution to get your IAC overspeed error corrected?

 

Get your car warm, then while at idle, disconnect the IAC valve electrical connector. Does the idle drop dramatically, or stall. It should. If it doesnt, then either your IAC valve is stuck open, you have a vacuum leak, or your throttle body is cracked to far open. Single blade throttle bodies have always been tricky to get right.

Being you have an Accufab, I would call them and see what they say. A heavier return spring could fix it, but without starting a throttle body war, I just recommend calling them for a fix.

Actually you want to rev the car off idle for 5 seconds so it's definitely closed, then disconnect the connector to the AIT valve and slowly close the throttle blade. If the car dies, then the problem is not the the throttle blade, but I have a felling that it will just idle normally. This is the time where you want to set the throttle blade idle stop screw. You should set the screw so the idle drops as low as you can get it without the throttle sticking when you press on the gas. If you have a voltemeter handy, you can check the TPS voltage and try to get it as far under 1V as you can, but not lower then .75V. Shut the car off, reconnect the AIC connector, disconnect the negative battery cable and turn on the headlight switch and leave the car that way for 2 minutes. Then reconnect the battery and it should be ok, but it will still do the 1100-1000 RPM idle down, but should idle at 800-850 RPM. Hopefully that works out for you.

 

My car idles about 800 but when i drive it and come to a stop it will hang at 1000 untill i step on brake it then will come down to 750 .Accufab told me to adjust the TPS by turnin it counterclockwise but that didnt help.How do you add another spring?

 

This is how I installed mine.
You don't need much of a spring.

Dana

 

Ok i think i can manage that. I was thinkin the added spring was coiled around the linkage like the one all ready on the Tb .Thanks ill give it atry hopefully it will cure my SES light problem if not i might be going back to my stock TB

 

That code pops up because the accufab TB flows more or less air than a stock TB, when the throttle is closed. If the car is an auto you'll probably notice some surging when shifting gears or when the AC comes on and off, because the autos are more sensitive. On a manual car you probably won't notice it too much.