Hey guys. I have a VIII with 96k miles and my car likes to throw random misfire code. I have cams, turbo back with no cat, everything else is stock. I checked the plugs when I got home and they all looked like they were firing. Replaced them less than 7k miles ago and gapped to about 22. They were at 27ish which I thought was the problem but that didn't fix it. If its the coils then how come the plugs look like they were firing? If it was fuel pump, or injectors then I shouldn't be smelling fuel correct? Could it be cam position sensor? Or the fact that I have not gotten my car tuned yet? Bare in mind it hasn't been long since I had the cams installed and I lowered the boost until I take it. Also this problem didn't start immediately after cam install but much later on. When it's cold it sort of feels like it hesitates until it gets to normal operating temp which is probably why my plugs looked normal. I don't see any coolant in the block and I have not been losing coolant so it can't be the head gasket. What should I look for next?! Gas smell isn't good!

 

Are you aware that just about any Evo 8, regardless the condition of the engine, sooner or later starts throwing this code. I'm not saying there isn't a problem with your engine but it may be an Evo 8 feature that can only be fixed by changing code in the ECU.

 

Strange, I have 106K on mine and it has NEVER given me this code much less any other code.

First thing I noticed is the OP says it doesn't have a cat. I know that doesn't explain the code he is getting but it can't help either. As for the gas smell start checking hoses as the car is bordering on 10 years old.

 

Can I check back with you in a couple of years before I admit I am wrong?

 

I've been coming across many threads about this issue and 8's, and a tactrix cable is in my future. But it still doesn't explain the gas smell. Injector seals possibly? I kind of noticed a few might have some cracks so it'll be wise to replace them. What kind of hoses would you be talking about? Fuel lines? The smell is more prominent inside the car but when I stick my nose near the engine I can smell it as well.

 

I think I may have figured out the smell. I think I have an exhaust leak but I can't figure out where it's coming from but definitely from somewhere on the DP. Would that cause a misfire though? Again, no cat.

 

no, it would not cause a misfire. sounds like a spark issue to me... either blowout at high psi ( mine are gapped to .020 btw to keep from blowing out) or maybe a bad coil. I had one fall apart when I pulled on it to change plugs this weekend.

 

under no boost it misfires. damn, I would hate to buy coils and it not fix the probem but I do have 96k miles so it might be time anyways. Any good places to order them without breaking the bank?

 

Your cams and clutch, then add the fact it wasnt turned off in the tune. P0300 is a code that has plagued Mitsubishi's since 1990 for no explainable reason and definitely not because its a real misfire.