Surging at idle GM 454, transmission clunk..
I know I have seen this discussed before but, I can't find it. What causes a idle surge on the Chevrolet 454 TBI? Seems like it was a simple fix. When the engine is fully warm and we are easing thr...
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It could be the Idle air control valve (IAC) It is mounted with two small screws on the lower right side of the Throttle body.
Not sure what year your rig is. The THM 400 has a vacuum modulator, the 4L80 doesn't.
You might want to verify what engine transmission you have. The 7.4 TBI has the 4L80 transmission.
I
Not sure what year your rig is. The THM 400 has a vacuum modulator, the 4L80 doesn't.
You might want to verify what engine transmission you have. The 7.4 TBI has the 4L80 transmission.
I
