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[Lorrin Barth]

USDM Lancer Evolution VIII p0300 code

This may have happened while driving the new car home from the dealership or it may occur after the vehicle has some miles on it.

This topic is for the Evo 8 not the Evo 7 as in the heading. The Evo 7 was not sold in the US and where it was sold this test was already set to off by the maker.

Symptoms – driving on the highway in 5th gear at 3000 rpm the engine stumbles and begins to run rough. Also, a CEL is set. Pumping the accelerator will clear the problem for several minutes, then it returns. Cars more severely afflicted may set the code in any gear at any speed.

The maker, Mitsubishi, has never come up with a repair for this issue. However, there is a permanent fix available via youtube.

Update: Checked for the repair video on youtube. It is now set to ‘private – log on if you have permission’. So, that is out. Next best choice is –
http://forums.evolutionm.net/ecuflash/377898-disable-p0300-test.html

Topic