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05 Corolla high rpms can't smog

Baffled that my well-maintained 05 Corolla couldn’t smog today. Smog checker said rpms were too high and it got kicked off the machine six times; said he had replaced his cable today. Any ideas? Manual transmission, 96,000 miles and had oil change last week; 93,000 major service included flush of something. Thanks for any advice.

This could be many things but I would look at things like your coolant temperature sensor, MAF sensor and TPS. MAF is the mass air flow sensor and TPS is the throttle position sensor. A failure or deviation in performance by any of these would give you the symptoms you are having. Do you have a check engine light (or have you had one recently)?

Also, a dirty throttle body and IAC could be the cause. A dirty throttle body that prevents the butterfly valve from closing could lead to high RPMs without triggering a code.

@BustedKnuckles - That’s a great thought. A quick cleaning of the throttle body is worth a try since a can of cleaner is cheaper than all the other potential solutions.