Q: Check engine light on, codes for air intake temp sensor, catalytic converter, and knock sensor. Car is bucking when going uphill.

asked by on March 08, 2018

Recently purchased the car. Check engine light would come and go for a few days but then stayed on steady. Scan shows for catalytic converter, knock sensor, and air intake temperature sensor. Car drives ok but has been making a chirping noise and bucks when going uphill. So far I have replaced the air intake sensor, new air filter, and used a catalytic converter cleaner.

My car has 211000 miles.
My car has an automatic transmission.

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If the check engine light is presently on your most efficient option would be to request a check engine light diagnostic. The mechanic will resolve all codes and then re-evaluate your situation, that is determine if the engine still misses under load even after all codes have been investigated and resolved. Note that diagnostic trouble codes only provide clues as to the general area of the problem. Consequently, unless you actually tested the air temperature sensor and pinpointed a failure, the sensor might have been perfectly good. For example, you can obtain the identical fault code for the sensor just by disconnecting the wire to a perfectly good sensor. Chirping noises are often serpentine belt related, if not the belt then an issue with the circuit of rotating components. If the check engine light is not on, but you just want the bucking diagnosed and fixed, as well as the noise issue, please instead schedule service via YourMechanic’s engine loss of power diagnostic page. With regard to either diagnostic, if you request service the certified mechanic will get your issues resolved for you, right at your location. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

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