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Q: codes p0101 and p0303 simultaneously

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I continue to get codes p0101 and p0303 when throttle is near wide open on highway on ramp (60-70mph). The fuel pump, filter, plugs, wires, cap, rotor, injector spider, and delco ecm have just been replaced in an attempt to correct this condition. The engine runs smooth until this speed, when you can feel a shudder and the check engine light illuminates. Cylinder 3 has 185 psi compression check, and continuity was checked on ecm etc.

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

A: The code P0101 is for a problem with the MA...

The code P0101 is for a problem with the MAF sensor and code P0303 is for a cylinder number 3 misfire. The first thing to check is to make sure there is no vacuum leaks or leaks between the MAF and the throttle body connection hoses. The MAF may be giving an incorrect input to the computer causing the misfire and MAF code. Have the MAF code pinpoint test done and replace the MAF if it fails the test.

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