Q: Flashing check engine light.

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I have a flashing check engine light comes on then goes away while accelerating in 2nd or 3rd gear. P0301 is the bad code. I have changed Spark plug, wire and fuel injector on cylinder 1. I will replace my distributor cap this week. I do not have a catalytic converter. I have also seafoamed the truck twice with no luck.. truck is running rich and I have loss of power. it started last week 7/26/16 and I have been taking it easy while driving. What else can I check and/or replace to fix this issue?

My car has 185000 miles.
My car has an automatic transmission.

If you keep having code P0301 come back, and you have replaced the injector, plug, and wire, then you may have excessive carbon build up on the valves or you have low compression in the cylinder. Since you had the engine sea foamed twice, it may have cleaned some carbon off the valves but not enough. You may need to do a compression test and have an engine decarbonized by flooding the engine with combustion chamber cleaner and shutting off the engine. Let it sit for thirty minutes and then start and run the engine by revving it several times and then hold engine at 2500 to clear the engine of carbon. If you want to have this checked out, a certified technician from YourMechanic can come to your car’s location to diagnose the vehicle’s loss of power and let you know what needs to be done.

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