barneyb

Years ago, when I encountered a stiff heater control, I knew I could get a copy of the heater TSB from NHSTA. I filled out the online form and a week later a fat envelope arrived. With the instructions enclosed I fixed my heater. Well, there were other papers I never looked at.

Tonight, down in my office stuffing the shredder, I ran across this stuff and found the government had enclosed another TSB entitled “Random Misfire (DTC P0300 P0301, P0302, P0303 or P0304) - worn input shaft 5th gear spline, misjudged by the PCM as a misfire.” dated April 2006. I've fixed my P0300 problem by getting into the periphery bits and deleting the test. But, I always wondered what actually was (is) wrong. This when I've had the information sitting on my shelf for years.

Car affected are 2003 – 2005 Lancer Evolutions with the 5 speed transmission made before 7/04.

Testing involves driving the car in 4th gear. Is a DTC set? If yes apply new software or fix whatever mechanical, fuel, or ignition problem is causing the DTC.

No DTC in forth gear? Drive the car in 5th gear above 60 mph. “Then slightly release the accelerator pedal for 10 seconds. During the 10 seconds, press and quickly release the clutch. Repeat this at least 2 times.” If a DTC occurs read the DTC and freeze frame data checking that coolant temperature is higher than 167 degrees F, engine RPM more than 2500 rpm, vehicle speed is above 60 mph and engine load is less than 80%.

If a match then replace the transmission input shaft with MN107628, replace input 5th gear with MN107624 and replace the input shaft oil seal with MD746516.

Since this TSB is old the part numbers may have changed.

So, if you've wondered, here's the answer.