Q: Running lean and I can't find a vacuum leak. Sometimes vibrates at various speeds. I let off the gas and then there is a lack of power.

asked by on December 16, 2016

Keep getting lean code when clear it comes back when warms up I have change the mass airflow sensor map sensor plugs wires fuel pressure regulator and all 4 O2 sensors it stumbles on acceleration sometimes at speed feels like driving on Rumble strip let off gas goes away

My car has 240000 miles.
My car has an automatic transmission.

Spark Plugs Replacement $113.11 - $716.47 Get a Quote
Engine Mount Replacement $132.06 - $1865.27 Get a Quote
Car is shaking or vibrating Inspection $94.99 - $114.99 Get a Quote

Hi there. For the vacuum leak, look at all of the vacuum hoses on the engine and brake booster. Check to see if the hoses are split, cracked, or unmounted. A vibration could be the engine running rough from the spark plugs being old or the engine mounts are worn out. Also, the spark plugs would cause the engine to hesitate on acceleration. If you need further assistance with diagnosing your engine issues, then seek out a professional, such as one from Your Mechanic, to help you.

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