Skip the auto shop - Our mechanics make house calls

Q: codes p0101 and p0303 simultaneously

asked by on

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.

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.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: My yukon is running like nthere is something terribly teribly wrong

The mass air flow sensor measures the speed of the air going into the engine. The P0101 code could be an electrical issue. The PO449 code is related to fuel tank emissions. Codes give you the area of a fault...

Q: my 2001 chevy express overheating,start leak coolant,vent back to mechanik who replace radiator 3 mon agoy,been told fan cluch nat

It is entirely possible the fan clutch has failed. When this happens, the fan will not pull enough air through the radiator and cause the engine to run hot. Generally there are two types of fan clutch designs. One is...

Q: Truck is running rough engine light. Keep call code

The catalyst may give off a rotten egg smell if you are running rich from an engine misfire. You will need to have the two cylinders that are misfiring diagnosed to see if they have low compression or the valves...

Related articles

How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.