Cylinder misfires or bad injectors, please post here.

I have a 1998 Legacy GT LTD. The engine light now comes on (cylinder 4 misfiring) or off depending on the amount of gas in the tank. It's not an exact pattern but it is predictable. Any ideas?

It turns out there was a bad valve, so they are replacing the valve and the cylinder under the powertrain warranty. However I still need to pay 230 for the fuel injector cleaning they did and the initial diagnostics.

 

I thought these boxer engines were supposed to run forever, I'm shocked that I am having this problem on a car that is only 3 years old. It is making me think twice about buying another subaru.

They trying to shaft you for the injector cleaning Call SOA.

Only 21k with rough idle.Dealer said all he could do was injector cleaner for $ .Looking for a fast and easy solution I said ok.Car ran as smooth as new on the drive home.3 days later and idle is rough again.So it must be the injectors and I will return for warranted replacement as soon as convenient.

They trying to shaft you for the injector cleaning Call SOA.

 

I may call them one day but what could SOA say?

At about 60K my 05 Outback XT got cylinder #2 misfire codes. The idle is also rough when partially warm (line a minute after being started cold). Dealer replaced the fuel injector, recommended using Chevron gas. Did that, but the code is back. Spark plugs are new OEM, the dealer tried changing coils but it did not help.

 

The dealer does not know what's wrong, and I hate to pay for them to replace good parts. After reading this tread, I think they should have swapped injectors to see if the problem follows the #2 cylinder injector, for example.

 

Any suggestings on how to proceed?

Edited September 20, 2008 by OXT

Do compression and leakdown test. Bad idle sometimes can be due to cracked piston ringlands. But then you would see some oil consumption most likely.

 

Also check the banjo filter on the driver side (very hard to get to). There are reports that when clogged it could cause bad idle.

Do compression and leakdown test. Bad idle sometimes can be due to cracked piston ringlands. But then you would see some oil consumption most likely.

Compression and leakdown are OK. I am more worried about misfires than rough idle, I mentioned the latter because they may be related. Also, no significant oil consumption.

Update: took a car to a different dealer, they claim my valves need adjustment and are bend. This sounds strange -- I thought the car had self-adjusting valves.

Are valves covered by the powertrain warranty?

P0301 and P0302, is that misfire on 1 & 2? Sorry, not so good with Subaru engine codes

Is there any long term damage to the engine if the light comes and goes? Filling the gas tank and the brand of gas seems to have a direct effect on the idling (and light) coming and going.

Yes. Carbon build-up on valves is getting bigger and bigger. After some time you will get misfire with any brand or octane of gas. Try 94 gas and see if you will continue getting misfire. If no - as you mechanic to use TerraClean solution to clean valves. It did the trick for me. I'm no longer getting any misfire on any type or brand of gas.

Just got a CEL code last night on my 05 LGT w/ 34K miles on it. Took it to autozone today and they said it was a "P0301 - Cylinder 1 misfire detected".

 

The car is acting fine though....no rough idling or anything.

What gives??? :confused:

 

Please help

Just got a CEL code last night on my 05 LGT w/ 34K miles on it. Took it to autozone today and they said it was a "P0301 - Cylinder 1 misfire detected".

 

The car is acting fine though....no rough idling or anything.

What gives??? :confused:

 

Please help

 

 

Misfire could be the result of many things. Problem is there is no way anybody on here would be able to tell exactly what it is. Take it to the dealer, your stock and still have your warranty let them deal with it, and dont worry misfires happen.

+1 clear it & be done with it

Thanks for the info HLS!!!

I have a 1999 Legacy GT 2.5 non-turbo and have around 164k miles on the car. Just yesterday my engine light came on and checker said it was a p0304 #4 plug or wire misfire. Is everyone with this problem having bad injectors or should I start with replacing the plug and wire. Any input would be help full.

 

Ps-after resting the code, this light comes on after a few drive and then starts flashing under acceleration then stays stead while driving.

I've got the same problem (i.e. P0304 code) on my 05 GT. After doing some searching and doing some research on this site, I've noticed an alarming trend of #4 cylinder coil pack, injector, and OCV failures. Here are my problems. My car idles poorly, not shaking, but poorly. It starts off with a bad stumble, but when it reaches a certain rpm, it starts to run better, not perfect, but better. I've replaced the drivers side OCV, this "seemed" to have made the idle better than it previously was (maybe it was wishful thinking on my part), still threw a P0304 code. I've checked for leaks and can find none. Here is my problem that nobody else has seemed to touch on, it has a lazy start. What I mean by that is, when I start the car, it is not the crisp, on one crank, start, it seems to roll before starting (hope that makes sense). The first shop I took it too said the compression was low in that cylinder, but that was before I replaced the OCV, so, I may have multiple issues going on here. I'm going to replace the #4 coil pack next, and then the injector, but, after that, I'm out of ideas. Any other advice out there from the esteemed panel of experts (no kidding, you guys are a lot of help). Thanks.

I'll join this club, I have a random cyl 4 misfire, way more pronounced within the first ten mins of driving. When it is super cold, it throws the code within 5 mins. Idles rougher when cold. Runs great in boost. Running dw740s. Def worse when cold. Any ideas if that sounds like a coil pack, or injector?

I just had my block and turbo replaced under warranty and 1200 miles later, cylinder #3 misfire.

wow, thats insane, well i just pulled my plug, and there is no oil on it, so the ringland failure is out of the picture! Now i lost that damn spring the the coilpack!

I dont know what is going on here! I am having what I believe is a misfire issue. It is however not throwing any codes. The symptoms are as follows:

 

1. When I free rev the car it stalls and dies

2. When driving the motor has hesitated and bucked really bad in any gear between 2k-3k rpm

3. The biggest issue is when it starts making boost it starts missing and breaking up real bad.

 

Plugs have been replaced. There is fuel pressure. There seems to be no vacuum leaks or anything. I do not know what is going on. My tuner is kind of stumped as well. Any and all advice is wanted, needed, and greatly appreciated. Below is a video of the car on the dyno doing the breaking up thing.

 

IMG_0339.flv video by s13slider44 - Photobucket@@AMEPARAM@@http://vid79.photobucket.com/player.swf?file=http://vid79.photobucket.com/albums/j133/s13slider44/IMG_0339.flv@@AMEPARAM@@vid79@@AMEPARAM@@79@@AMEPARAM@@j133/s13slider44/IMG_0339

Edited December 29, 2009 by 2.5gtbx_44

I had a misfire issue several months ago, cylinder number one if I remember. The car would start up fine and rev ok but after driving like a mile it would sputter really bad then die. Once it did that it would not start for about 3-5 min, then start up fine and I could drive normally again.

I had a friend who’s is a Subaru mechanic come over with his diagnostic computer and he couldn’t really figure it out. We moved stuff around to see if the misfire would follow but it never did. It ended up being a dirty MAF, I had pulled it out and the little bulb sensor was visibly dirty. I sprayed it with some cleaners and put it back together. After that car was perfectly fine.

Thanks for that, Break Beat. I'll look into it... I'm having pretty regular P0301 codes on my '05.

Maybe I'll try the moving the injector also to check it?

 

The first time it happened, I was sure I'd blow the car up (and I didn't yet know the trick to check the code myself) so I took it to the dealer ASAP. They screwed around with it for a day and decided to change the cylinder 1 coil. Two days later, after replacement, I got the CEL again, same cylinder (P0301).

 

Now I can almost guarantee a CEL will come on if I idle for more than about 2 minutes. Of course one shouldn't idle for that long, but tell that to the traffic on the QEW or 401 Highways!

Eventually, the CEL will go out on it's own after 100 km or so of driving, and a couple of re-starts.

 

Could a dirty MAF cause this?

Well my issue was a bad coilpack. I dont know which one or how it went bad but, I replaced all of them to be sure and that fixed the problem straight away. Just a FYI for anybody going through the same issue as me.