[HWYSTR455]

Or the throttle blades are hanging up. Is the throttle return spring too weak? Is the throttle cable hanging? If it's not fully closed when you turn the key on it will use whatever position it's at as 0% (TPS autoset occurs at every key-on)

If the IAC AND the TPS are at zero, sounds to me that the throttle blades aren't closing all the way, and it's referencing the open position as 0%. Maybe take the throttle body off and check to see if there's any witness marks on the gasket etc, and that they are near closed.
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Any exhaust leaks?



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