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2003 6 with CEL codes P0300, P0303, P2177, P2187

andramont726

New Member
Hello,
This is only my first post so please be kind
I've got a 2003 Mazda 6 2.3L that is currently suffering from a very rough idle -- it runs fine under acceleration. The only mod to the vehicle is a cold air intake that was installed 6+ years ago.
I removed the filter for the CAI a couple of months ago to clean it, and then not long after that I got 2 DTCs: 2187 and 2177 (System Too Lean off Idle and System Too Lean at Idle).
So, then I used my scanner and OBDWiz to clear the codes and log the performance. I then got P0300 and P0303, in addition to the original P2177 and P2187 codes.
I know that some of the things to consider are the MAF sensor (which I have cleaned), the front O2 sensor, vacuum leaks, the PCV valve hose, etc. I have also heard that the CAI can be the culprit, but since this one has been working fine for several years, I don't think it's the problem.
What I am wondering is if the information saved from my scanner will give me a clue so that I don't have to play trial and error with a bunch of expensive parts. I've attached the log file recorded while sitting at idle, the trouble code report, the freeze frame report, and the On-Board Monitoring report.

If anyone can give me some advice I would certainly appreciate it
!
 

1Kris06

MAD LIGHTS YO
P0300 Random misfire detected Flash / ON 1 or 2 Misfire ´ (See DTC P0300)
P0301 Cylinder No.1 misfire detected Flash / ON 1 or 2 Misfire ´ (See DTC P0301, P0302, P0303, P0304)
P0302 Cylinder No.2 misfire detected Flash / ON 1 or 2 Misfire ´ (See DTC P0301, P0302, P0303, P0304)
P0303 Cylinder No.3 misfire detected Flash / ON 1 or 2 Misfire ´ (See DTC P0301, P0302, P0303, P0304)
P0304 Cylinder No.4 misfire detected Flash / ON 1 or 2 Misfire ´ (See DTC P0301, P0302, P0303, P0304)

I'd check your plugs and coils. Plugs were an issue on my car (albeit, a V6)
 
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