Topic: P0302 - Generic misfire in cylinder 2

[AWDizzy]

So I was out of town for work and the wife got a CEL/flashing cruise while driving home from work. I took it to Autovalue tonight and got the code read (P0302 - Generic misfire in cylinder 2). I pulled this off iwsti;

Re: code p0302
Quote:
Originally Posted by blindfold
having an AP or being tuned has nothing to do with the seriousness of a misfire. Assuming your motor is fine, there could only be three things that could've caused the misfire

1. spark plugs, easy fix, get new ones
2. coil packs, swap them to other cylinders to see if misfire follows, if follows, buy new coilpack but inspect the connector first
3. injector, do the same thing as coilpack

The car has an AEM CAI, full APS catless exhaust and the tune in the ECU is locked (Sunny figured it's been tuned by Rocket Rally, since it came out of BC and he was unable to get into it when I had him look at the car after I bought it). I just replaced the air filter on the AEM intake (the old one was pretty haggard) and gave the car an oil change with bulk Motul about 1600k ago. Timing belt was replaced about 3000k ago as well. Apart from that nothing has changed recently.

I read some other posts on here where folks went through the above routine and more only to find that the wiring to cylinder 2 had been messed with (I believe from a remote starter..which I don't have) and this was the cause of the issue...So a couple questions;

1. Stupid question first...which one is cylinder 2?
2. Does the approach above sound like the best bet?
3. Is the wiring for cylinder 2 commonly used for any other aftermarket additions?

Thanks again.

[snackers]

1. Stupid question first...which one is cylinder 2?

#1 front passenger side
#3 rear passenger side
#2 front driver side
#4 rear driver side

That's all I can answer.

[Klautt]

With my 05, also with a AEM CAI & catless, I used to get the cylinder 2 and cylinder 4 missfire all the time. Almost everytime I went WOT. With a recent Airboy tune, those errors have past though, and I've only had maybe one since the tune. Changing my plugs was on my list to do next.. but with the tune fixing the problem for the time being, I'm procrastinating once again.
So my advice, is if your options 1,2,3 don't work, find a way to get a new tune up...

Also, do you have a knock light? that may be tied into a cylinder on the ECU wiring.

[Liehtw8]

I get the P302 code and 304 on my 05 sti as well. tbe, cobb stage 2.5 tune. (Tuned for Calgary's altitude). It happens when there is a big change in temp or I get crappy gas. Clear the code off with my scan tool and I don't see it again for a while. It only comes up every 3-6months. I found gas to be the huge culprit. Mine only does it on start-up when it does happen.

[Morison]

I just had P0303 (misfire on 3) and it was actually the connector to the coil pack that had broken/unplugged. A common problem is the clips breaking... I've zip tied the connector to keep it in an the code hasn't returned.

Sometimes - not always - it's the easy things.

[AWDizzy]

I get the P302 code and 304 on my 05 sti as well. tbe, cobb stage 2.5 tune. (Tuned for Calgary's altitude). It happens when there is a big change in temp or I get crappy gas. Clear the code off with my scan tool and I don't see it again for a while. It only comes up every 3-6months. I found gas to be the huge culprit. Mine only does it on start-up when it does happen.

This is interesting...Going to the mountains has put me in some situations where Husky94 was out of reach...and I have filled up with generic 91 octane gas from a few other places. I'm going to keep track of whether there appears to be any correlation to weather/gas a little more closely this time.
Either way, I've changed the cylinder 2 plug and the CEL has cleared up for now. The coilpack looked fine visually and hopefully that holds true for the guts of the thing too.
Cheers,
Jeremy