Cylinder 2 Misfire - Number/Location of Cylinders

I have read a lot of the posts and understand that this could be any one of a number of issues: spark plugs, coil pack, oil in wires, injectors, etc.

 

The first step I want to take is to swap the cylinder 2 coil pack with another cylinder so if the error follows the coil pack, I know its bad. Once that has been confirmed, I can move on from there. My issue is, I don't know which cylinder is which. Could someone tell me the numbered order of the cylinders and whether they are front/back driver/passenger side?

 

Thanks!

I'd check with someone else to make sure, as I'm not 100%, but I'm pretty sure cylinder 2 is, assuming LHD, driver's side frontmost

 

Pass-------Driver

 

ABS 3 | 4 Brake MC

Airbox 1 | 2 Batt

 

R---FRONT---L

Great, that is what I was looking for. Thanks!

He is correct. Are you using any oil?

Yes, I am using some oil. Is it related?

mine was a leaky injector if that helps. replaced the O-ring and havn't had a problem since.

Would the leaky injector cause me to be using oil? Or is that related to some other possible issue?

Maybe mine is a slightly different issue, but I have a few missfires. Whats been done:

Replaced all coils, spark plugs and wires, advances valve timing sensor, cleaned the MAF sensor. I still have missfires, dealer is unable to find the problem and im stuck with a stalling Subie. If you find anything that helps, please let me know.

Update.....

 

Plugs, wires, and coil packs were checked and no issues there. Compression and leak down test done with no issues found. I had the code cleared and I'm changing the oil to use a thicker oil. I have no idea why my car is using so much oil and my mechanics could not tell me either. No oil in the radiator and no bubbles during leak down test. Diagnostics test completed and car seems to be running fine.

 

Anyone have any ideas?

Also scoped the cylinders and no issues there.

You might have them do another leak down test. I had similar issues and had a leak down test done with good compression in all cylinders. The car was still running rough after a few days, so they checked the compression again, and after a second leak down test my cylinder 2 was at 5 psi... not sure how it passed the first test. Turned out to be a bad exhaust valve. Does your car run rough at idle? If so, it could be a bad valve. I checked all of the usual suspects, like you did; changed my plugs, swapped injectors, swapped coil packs, ect. So, back to what I said before, you might have them check cylinder 2 again for loss of compression.

You might have them do another leak down test. I had similar issues and had a leak down test done with good compression in all cylinders. The car was still running rough after a few days, so they checked the compression again, and after a second leak down test my cylinder 2 was at 5 psi... not sure how it passed the first test. Turned out to be a bad exhaust valve. Does your car run rough at idle? If so, it could be a bad valve. I checked all of the usual suspects, like you did; changed my plugs, swapped injectors, swapped coil packs, ect. So, back to what I said before, you might have them check cylinder 2 again for loss of compression.

 

 

Yes my car does have a rough idle. Kind of like a big cam in a v8. It seems to run fine except for a slight miss every once in while while at high RPMs. I don't ever notice a miss when cruising around town or on the expressway. It's only when I'm accelerating at high RMPs. I will try another compression and leak down test.

 

This is my first Subaru and I've only had it for 6 months. Right now, I'm thinking this thing is getting sold as soon as I fix the issue and I'm not coming back to Subarus.

Yeah, thoughs sound like similar symptoms to my car. Rough idle, seemed alright driving until I stepped on it. That's too bad you'll sell the car. Although I understand under the circumstance.

You might have them do another leak down test. I had similar issues and had a leak down test done with good compression in all cylinders. The car was still running rough after a few days, so they checked the compression again, and after a second leak down test my cylinder 2 was at 5 psi... not sure how it passed the first test. Turned out to be a bad exhaust valve. Does your car run rough at idle? If so, it could be a bad valve. I checked all of the usual suspects, like you did; changed my plugs, swapped injectors, swapped coil packs, ect. So, back to what I said before, you might have them check cylinder 2 again for loss of compression.

 

Do you have any idea what went bad with the valve? Did you have to repair the cyl head at all, or just replace the valve?

 

Two days ago I got the cyl 2 misfire code. The car would run on 3 cyls at idle but anything over idle the car feels great. Swapped injectors and coil packs, changed plugs, still cyl 2. misfire. Compression check showed 85lbs in cyl 2, 140, 140, 135 in all the others. I'm a quart low after 4000k miles. My engines coming out once I get my summer car back together. I'm hoping it is not anything too catastrophic.

No idea why the valve went bad. I was still under warranty, so I didn't have to pay for it. They didn't have to replace the cyclinder head, but they replaced all the valves to ensure they would all seat properly. They had to have an outside machinist do the seating of the valves. I've done this on motorcycles, using kerosene, to make sure there are not any gaps when the valve is set. If you do it yourself, I'd out source the valve seating, unless you know what you're doing.

I see. Thanks for the reply. I have to eat the bill as I'm at 96k miles now. Fortunately I have the ability to take the cylinder heads apart myself and my old boss owns a race cyl head shop locally, and the place i work now has a good relationship with Manley so I may use their valves. When I get back from vacation in a week I'll start planning the disassembly.

Well, I hope it all works out.

My 05 LGT Wagon is now experiencing this issue. My powertrain warranty just ran out July/09. I had the rough idle issue and p0302 code (misfire in cylinder 2). Sparks, coil pack and injector are all fine. Did a compression test and also found 5 psi. I'll let my mech know to check out exhaust valve. I think he had the head off today.

 

Is this a common problem? All I know is that this thing just came on VERY suddenly. It was fine one minute, then when I got home, rough idle. Didn't do anything stupid, didn't over-rev the engine, etc... Just a normal drive home.

I think it's more common on the 05's, but mine's an 06 so you never know. I saw my valve at the subaru dealership and you could see a small amount of one end burnt off. Usually it comes from using poor grade/brand gas. I only use chevron know because of it. But, I had never used anything other than 91 (the highest here)

Yup so one of my valves had the end burnt off as well. Lots of carbon build up. It was just waiting to die. We're not quite sure what is the cause, but my mech thinks bad gas is not likely the source. Getting a new head as well. I think I might go this weekend and snap some pics.

Same here. I got the driver's cyl head off this afternoon and one of the #2 exhaust valves is badly burnt, radially right through the valve head. With the size of the crack/burn hole, it's surprising I had 80psi in that cylinder instead of zero. I took lots of pics, gonna upload them soon. I'm bringing it to Ron at M2 Race Systems monday after work to see if the valve seat got damaged. I might go superghetto and only change the exhaust valves in that cylinder if the seat is ok. I need to get this back together ASAP as this is my daily driver and my other car is basically a track car and doesn't like the winter too much.

 

Oh, I checked the valve clearances. Shop manual says exhaust valves should have .014 +/- .002. The burnt valve had .005, the good #2 exh. valve was .012, and both Cyl 4 exh. valves were .008. All intakes and passenger side exhaust valves were within spec.

I just got P0302 misfire on cyl#2. My car seems to run fine. I cleared a code 3 days ago and CEL hasn't returned however i noticed at low rpm that car has a very little stuttering. I notice it but it's nothing crazy, just noticable. Obviously the problem is still there. Anyone had these symptoms where accelerating in like 2nd gear at lower rpm you'd feel very little stutter? Plugs have about 40-50K km on them. My understanding is that plugs should last 100K km??

I guess i could replace a plug on cyl#2, it's not hard. It's the back cylinders that are hard to replace. then see if that improves accelaration.

Any other thoughts?

My issues ended up being bad coil packs. Can't remember how much it cost me to have replaced. It was years ago.

I just got P0302 misfire on cyl#2. My car seems to run fine. I cleared a code 3 days ago and CEL hasn't returned however i noticed at low rpm that car has a very little stuttering. I notice it but it's nothing crazy, just noticable. Obviously the problem is still there. Anyone had these symptoms where accelerating in like 2nd gear at lower rpm you'd feel very little stutter? Plugs have about 40-50K km on them. My understanding is that plugs should last 100K km??

I guess i could replace a plug on cyl#2, it's not hard. It's the back cylinders that are hard to replace. then see if that improves accelaration.

Any other thoughts?

 

The lower rpm stutter, 2000-2500rpm is normal in these cars, a Good Tuner can fix that.

 

If your on the stock MAP, you may have a burnt exhaust valve in #2. That's the front drivers side cylinder.

Cylinder 2 misfire code has popped twice in the last 4 months. Car also studers when you really get on the gas from a complete stop. Car runs fine after it is moving. Car doesn't run any worse when the code pops. I just cleaned the egr valve to make sure the spring was moving freely. Any ideas