Q: Check engine light on, lost engine power 2x, now get 5-6 mpg less..ideas?

asked by on July 08, 2016

The check engine light has been on for quite a while, in the last 4 months the engine has lost power 2x, so I stop and restart to reset whatever needs to be reset. Now I'm getting 5-6 mpg less on my last 3 fills. Nothing else has changed. Tire pressure is where it's supposed to be. Once my mechanic referred to it being one of 2 things, he said they were side by side and had something to do with fuel evaporation. Any help would be great.

My car has 170000 miles.

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You will need to have the engine computer scanned again to get the codes and then properly diagnose any codes that are received.

Fuel evaporative codes may cause the truck to run richer than normal but should not cause the drop in mileage you see. There may have been another failure and an additional code stored. This is why it should be tested again. You may have caused problems with the O2 sensors or catalyst damage from driving with the other problems for an extended period of time.

I’d suggest having a certified mechanic diagnose the trouble codes again to pinpoint the root of the issue.

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