cylinder #4 misfire

I recently bought an 05 legacy GT. The car is completely stock right now with 50,000 miles. About a week after buying the car my check engine light comes on. Of course the cruise light flashes the whole time the check engine light is on, which is really annoying. Anyway my brother-in-law is a mechanic and brought his code reader over. The code reader says I have a misfire on cylinder #4. The misfire isn't terrible but it is happening. I thought it was just the "rough" idle associated with the Subaru boxer engine, apparently it's the misfire. So far we have checked the coil packs on the plugs and they tested good, and we replaced the sparkplugs which were due to be replaced soon anyway. After doing this [which was a MAJOR pain in the ass] the car still has the misfire. I guess the next step would be to test the compression of cylinder #4 [which I'm sure is a pain in the ass like changing the plugs] and also to replace the fuel injector on cylinder #4. I guess my question is, do any of you guys have any other suggestions as to what could be causing this problem.

Thanx in advance:cool: Micah

injector probably. You can double check the wire, by swapping wire for #4 with #2. Clear the code and see if code comes back, now with number 2.

You can do the same with the injector. but you can swap that with any cyl. and see if the code follows. .\

Throw in some fuel injector cleaner in @1/2 tank and run it through. May help.

 

O.

Thanx for the reply Osei. Sounds like a good idea swapping the wires from cylinder 2 and 4. I also like the injector swapping idea. I'll post the results and let you know what I find.

yea i had the same issue when i got mine a few months back...swapped fuel injector from 4 to 2 and cleared the code...couple days later the code followed to the second cylinder..ive done a bunch of research on it and most people end up switching the injector for the fix...goodluck

Yep, sounds like an injector problem. I swapped injectors (then the problem moved), then replaced the faulty one. I just installed a new, cleaned set of injectors from DeatschWerks on Monday.

same here. injector #3 went bad. switched it to number 1 and the problem followed.

 

PS injector number 4 is the one closes to the driver seat.

I hope this is my problem. I had to adjust my idle up 300 rpm so it wouldn't die.

After replacing the fuel injector the misfire is gone, for now! My legacy now idles really smooth and runs better than it has since I bought it a couple of months ago. Even though the spark plugs weren't the problem, I'm glad we replaced them. Now I won't have to mess with that for another 60,000 miles. I'm not sure if the injector was clogged or defective but swapping it for a new one seems to have fixed the problem. Thanx for the help guys.

When troubleshooting my injection problem, I tried injector cleaner and it didn't help. I think it just gets faulty. Glad to hear the problem is gone! Amazing how the car shakes less at idle when you have working injectors!