Q: My car has a high or surging idle

asked by on November 19, 2016

My truck is having idle issues. Sometimes it's normal. Sometimes it idles at 1300-1400. Other times it's right at 1000. Engine temperature makes no difference. Sometimes when i coast down the road in neutral or with the clutch pressed in the engine surges between 1000 and 1500. Truck has a new idle air control valve. Not even a month old. Would changing my TPS solve this problem? If not what could it be? I've put a lot of time and money into this truck to bring it back to life. This issue has me considering selling it. Please help. Thank you in advance.

My car has 166000 miles.
My car has a manual transmission.

Throttle Position Sensor Replacement $144.21 - $717.44 Get a Quote
Car idle is rough Inspection $94.99 - $114.99 Get a Quote

Hi there:

The throttle position sensor is the most common component that causes similar idle issues you’re experiencing, so it makes sense that replacing the TPS might be a good start. However, other issues could include dirty throttle body or fuel injectors, or an idle control valve that’s damaged or dirty as well. To determine the exact source, you might want to contact a mobile mechanic to have them complete an engine has a rough idle inspection first.

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