I have an 2002 F 150 XLT 5.4 V8. Lately my truck has been very shaky when i accerelate and put it into reverse. The Service Engine Light is on and blinks when I go over 50mph. I went to O'reillys to check the codes and it read o2 sensor and spark plugs. I got it fixed today but the truck is still shaking and the engine light is still blinking. I even tried switching to 93 gas and using a fuel cleaner. Any ideas of what it could be???

 

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There are no such codes, you've grossly simplified the code definitions into something that they were not intended to become.

If the engine light is flashing, you have a severe misfire. This is in your owner's manual.

Post ACTUAL fault codes, any interpretations are likely poor substitutes.

Post details about what was "fixed".

 

Failure codes do not always indicate every component in the system that can be contributing to the failure code. You can become a parts changer trying to track down the reason for a failure when it could end up being something else.