Just like how women need closure to everything, so does Natalia...

Thanks to Gecko69, the improperly fitted screens causing sputtering theory has been tested and verified success.

We installed it at the RPM meet, did some test drives, and on the drive back home to Scarborough, no issues, no CELs.

Let this thread close now, and hopefully when someone else has similar problems, they can refer to this as a guide.

Bottomline: Check your air screens for proper fitment.

 

Ive got P0420, Low Efficiency in the Cat.

I havent changed plugs yet, though I think they were changed during the 4520F recall. So got a appt at the dealership on Tuesday morning, to check it. So I get the line, ya its covered under your warrnaty, but if we find that spark plugs were the cause of the cel, your paying the service charge.

So, can spark plugs be a cause of this cel, unburnt fuel in the cat. My engine still maintaints its high revs, and notice no sputtering, redline a day without any issues. What do you guys think.

Gonna go pick up a plug socket tomorrow or borrow one to check the plugs out. Will post pics if I can.

 

I already got plug wires, and waiting to order plugs. Just holding out wiating for the BHR coil upgrade.

 

Copied this from another thread. I don't think P0420 has anything to do with your spark plugs.

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''P0420 = Catalyst system efficiency below threshold''

It looks as if the ''Hi-Flow'' CAT is not doing its job.
According to the workshop manual the monitoring condition for this CEL are;
1 - ECT = more than 158F
2 - Catalyst converter temp: more than 752F
3 - LOAD = 20 to 50percent (maximum calculated load values varies depending on engine speed)
4 - Time with purge control system does not operate: more than 20s

It also says possible causes are;
1 - Looseness of Front HO2S sensor.
2 - Leakage exhaust gas.
3 - Purge control system malfunction.
4 - VSS malfunction.
5 - ECT malfunction.
6 - Eccentric shaft position sensor malfunction.
7 - PCM malfunction.

 

Can someone help me please?
I noticed my CEL came on too this morning when driving, it was raining quite heavy as well. I did not accelerate past 4k at any point (Hwy speed)
I currently have the AEM CAI installed, and I can definitely feel the filter is wet.
Is it safe to continue driving at the moment? What should I check to hopefully clear the CEL?

 

Just a wet filter... no problem, just let it dry, it'll be fine.

 

Wow after reading all 7 pages, I love it. Same exact problem I'm having. Was told to replace my ignition coils, wires and spark plugs. After that CEL came on again, was told that they found code P0300 through multiple diags. They said they performed a compression test and found two cylinders to have carbon build up. Had it decabarbed earlier and still got the CEL after. Car feels much better but still have that problem between 6-9k RPM. Heading back in the morning to tell them to check my MazdaSpeed CAI.

 

Who installed your CAI? Avante Mazda? I think Footman got his from Avante....

 

Nope had mine installed by Star Mazda. Hoping they got the installation correct.

 

footman...u leaving the MS CAI on for the winter?

 

I left my CAI on past winter no problem. It's staying on all year round.

 

cool! I can't be as bad as last year....I hope!!