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DylanWest42

New Member
Nov 23, 2025
1
0
1
United Kingdom
Just yesterday my I30N with just under 12k miles all of a sudden started spluttering and ran super rough with no engine light weirdly. Got it back home and done some diag myself and found that cylinder 3 is misfiring, swapped spark plugs and coils around and still coming from cylinder 3. Used a scan tool to check live data and disable cyl 3 injector and made no difference to the idle. Only fault stored is P030300 cyl 3 misfire.

So judging by that the injector may have gave up which is quite surprising considering the mileage, are injectors common to go? I know the hpfp is a common issue but idk about the injectors. Maybe the previous owner thrashed the car when they had it? I’ve always ran it on momentum 99, I usually fill up with about 10-15 miles range left if that would make a difference? Filled up Wednesday and misfired by Friday.

Still under manufactures warranty so hopefully will be sorted through them.
 
Sounds like a random injector failure, not common for the I30N or EN but you've done all you could. Let us know what the dealer says.