LostinCanada
Member
- :
- 2003 Mazda Protege5
Hey everyone, I just read through a wackload of threads re P0302 and P0421 codes but none of them sound like what just happened to me. As a side note, this car hasn't had a check engine light for over a year, since I did the quick and dirty on-the-car ring job and rebuilt the head. Plugs, EGR and many other things replaced new OEM. My car has been running awesome ever since.
Two days ago I got a CEL so I fired up the Torque app and found the P0421 - Powertrain: warm up catalyst efficiency below threshold bank 1 code. So I cleared the code and have been monitoring with the Torque app running since (just city driving - no highway). I got a pending fault warning a couple of times for the same code but the CEL never came on. This afternoon, I suddenly got the CEL - this time it was P0302 - Powertrain: cylinder 2 misfire detected. Shortly afterwards the idle dropped about 100 rpm and started behaving erratically at the stop lights. When I came off the light the CEL started flashing (not driving fast at all, but during the acceleration). I wasn't far from home so I took it easy but still got the flashing CEL. Clearly something is wrong and it seems to be sudden.
I don't know if it's related but when I got home I realized I left the sunroof partially open so I turned the key and closed it. That's when I heard this weird electronic squeal. I heard this noise once before about a month ago, when my battery drained from letting the car sit for a couple of months and the battery became too weak to hold a charge anymore so I replaced it.
Am I having an electrical issue of some kind? Hopefully I'm not looking at replacing the entire parts catalogue as others have done trying to figure out these codes!
Before someone says coils I can pull the old coils off my parts car and take a test drive tomorrow but I'm wondering about getting this P0421 first and then a sudden misfire. And then of course the random electronic squeal (key on/engine off).
Two days ago I got a CEL so I fired up the Torque app and found the P0421 - Powertrain: warm up catalyst efficiency below threshold bank 1 code. So I cleared the code and have been monitoring with the Torque app running since (just city driving - no highway). I got a pending fault warning a couple of times for the same code but the CEL never came on. This afternoon, I suddenly got the CEL - this time it was P0302 - Powertrain: cylinder 2 misfire detected. Shortly afterwards the idle dropped about 100 rpm and started behaving erratically at the stop lights. When I came off the light the CEL started flashing (not driving fast at all, but during the acceleration). I wasn't far from home so I took it easy but still got the flashing CEL. Clearly something is wrong and it seems to be sudden.
I don't know if it's related but when I got home I realized I left the sunroof partially open so I turned the key and closed it. That's when I heard this weird electronic squeal. I heard this noise once before about a month ago, when my battery drained from letting the car sit for a couple of months and the battery became too weak to hold a charge anymore so I replaced it.
Am I having an electrical issue of some kind? Hopefully I'm not looking at replacing the entire parts catalogue as others have done trying to figure out these codes!
Before someone says coils I can pull the old coils off my parts car and take a test drive tomorrow but I'm wondering about getting this P0421 first and then a sudden misfire. And then of course the random electronic squeal (key on/engine off).
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