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Q: RPM revs high

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When we go to start up our car the rpm revs to the 7 (red lines) and then goes down a little and then goes up and down so we checked our fuses and the abs motor relay fuse is gone.. Could that be related.? Or whats wrong with it, why does my car rev up so high

My car has 144 miles.
My car has a manual transmission.

A: Hi and thanks for contacting YourMechanic. ...

Hi and thanks for contacting YourMechanic. Check the IAC (idle air control valve) to the engine. This will cause the RPM's to fluctuate up and down to a dramatic amount. Look at the wiring to the IAC and make sure that there is no corrosion, loose wires, or any burnt pins. If the harness seems to be good, then I recommend replacing the IAC with an OEM part. If you need further assistance troubleshooting your vehicle, then seek out a technician, such as one from YourMechanic, to pinpoint the correct repair for the high RPMs.

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