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· Registered
5 Posts
Discussion Starter · #4 ·

Here's what's up: Got P0301 , which is injector misfiring, that was so bad it came up twice lol
Next we have P050B, which is a Cold Start Ignition Timing Performance one
Next P0300, which is another injector misfiring; piston #2 in this case iirc
P0302: you guessed it: another misfire. Cyl 3 ofc

What could be causing all of these at once?

· Administrator
30,158 Posts
Our 2011 had the burned valve thing at 34K miles so you're doing well at this point. Because of the relatively low miles MBUSA picked up a lot of the cost - I wouldn't expect them to do that with 75K on your car. They charged over $2K for a brand new head - maybe a local machine shop would be less once the parts are in hand. :)

· Premium Member
11,314 Posts
possible the p0300 series codes are from bad ignition coils, which could trigger the p050B code (have not seen that one before) You could try new plugs and coils, but that would be the old shotgun fix without verifying the compression. If it is a compression issue, we have seen owners use Marvel Mystery Oil with some success to free stuck rings and get the codes to go away.

Unfortunately the size of the spark plugs requires a adapter for the screw in type compression tester
but that is the best way to check compression, which should be the starting point. Hate to waste the $$ on plugs and coils if it has low compression, with it listing the P301 and a p302, it is possible it is a head gasket or worse..
P300 is a Multiple misfire, P0301 si cyl 1, P0302 is cyl 2, etc. These relate to the spark plugs and not the injectors.

Wouldn't hurt to check Battery condition and grounding wires as they could cause erratic error codes too.
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