Hi,

I have an 03 Evo VIII.

I have 90K miles, with mods in sig. Lately, car throws p0300 once a week or every couple weeks. Lately, car has started to "smell" more at idle and even while driving. Smell is "exhaust-like", but could it be fuel from running rich aka misfire? I had tried gapping the plugs down (.024 or so), and it seemed to help a little at first, but now it's starting to smell again.

Could the ignition coils be getting old? If so, would something like the SparkTech help? My plan is def to stay stock ECU, although I may go stroker and "small" turbo upgrade, so I would probably stick with the non CDI solution.

Alternately, it's probably some sort of leak, right? Any things in particular that would cause the exhaust or possibly fuel smell?

Thanks,

FB

 

Hi again,

I ordered new plugs, but the car seems to smell like exhaust, so it must be an exhaust leak somewhere. I listened along exhaust while it was running, but didn't find it.

It seems to be coming more from the front, since I can smell it while driving, so it would probably be at exhaust manifold/dp, etc. Is there anything else to check, for example, the EGR valve?? When the EGR valve is old, can that cause something like this?

Any insight is appreciated.

TIA,

FB

 

bump someone help him out.

 

Heh,

Thanks for the bump

I got some new plugs (BPR7ES) which I'll try, but I'm thinking it's some sort of exhaust leak. I just wanted to see if the EGR valve or something other than an exhaust leak could cause the smell. As I thought about it more, could it be a clogged cat? I've had my Random Tech HF cat for a few years now.

In the meantime I've been driving my wife's CRV around, which kind of blows, lol.

Take care,

FB

 

bump. i have the same problem, that dreaded p0300 code.

 

Hi,

Just an update, I ordered some Okada coils. I will install them along with fresh NGK plugs (bpr7es) and new plug wires. If this doesn't help, I'll focus on the exhaust leak.

The p0300 hasn't been that frequent. I didn't really get it before (dynoflash), but did get it a few times since the recent reflash.... Fresh plugs with a tighter gap seems to have helped.

Take care,

FB

 

Hey all,

Well, before bringing it somewhere to try to find the exhaust leak, I installed a fresh set of plugs and my Okada coils. Disconnected the battery to reset the ecu and went for a drive.

Idles much better, and runs much smoother. I drove it for about 15 minutes, and I did not smell the exhaust/fuel smell that has been plaguing me. The day before I drove the car to work and by the time I got there, I could taste exhaust and I didn't feel that great... When I got home, my wife confirmed that I smelled like exhaust....

Anyway, we'll see if it helps with a normal commute this week. I would be surprised if unburnt fuel was causing the smell, but it definitely seems like the smell is not nearly as bad as before. No codes yet either. I opened the gap up every so slightly (~.027 now).

The Okada coils are nice, although kind of spendy. Still, I had 90 K miles on the stockers, so I feel better replacing them anyway. I'm trying to source some Ralliart wires to replace the stockers and I'll get some fresh boots as well. If the smell comes back, I'll see if a shop can check the whole exhaust system and gaskets for the leak.

Take care,

FB

 

Hey, sounds like the coils are working, but it may be just that the old ones were getting old. I'm still researching the whole Okada/ARC2/COP systems.

Anyway if you have an exhaust leak, fresh air is probably getting into the exhaust flow and "could" be causing your O2 to read lean and add fuel to compensate making the mixture more rich that it needs to be to make the O2 feedback happy. Just a though, exhaust leaks are not good, especially before the O2.