New Legacy...with misfiring baggage

Hi all, I am coming over here from nasioc as I just picked up a 2003 legacy L (auto, 123xxx) for $2k from our local subaru dealer. Great price, i know. the baggage she came with is a rather rough running engine. I pulled the codes it is throwing and I got

-p0301 - misfire cylinder 1

-p0302 - misfire cylinder 2

-p0303 - misfire cylinder 3

-p0304 - misfire cylinder 4

Uh oh. the dealer said that the car needed a new engine. I wasn't that convinced, the car idles rough, has a little hesitation when trying to accelerate, but doesn't stall out or anything like that.

I pulled all the plug wires while it was running and while they all seemed to have power going to them (ie you could hear the "tick, tick, tick" of the power arcing) only cylinders 2 and 4 seemed to affect the way the engine ran (bogged it down)

It seems like it has to be something electrical, but i figured I would see if anyone on here has seen this before I go it alone! Thanks in advance!

It is always easiest to rule out the most obvious things...I usually start simple

1.Plugs

2. Wires

3. Coil

4. Timing

5. ECU and Sensors: cam, map, you get the picture

While you have the plugs out you may want to do a compression test as well to rule that out or confirm it is a problem.

Update:

I pulled all the plugs, and it seems that cylinder 1 and 3 had oily or gassy plugs, I can't tell which. I tested the resitance of the wires to the best of my ability. I got about 9.5 for 2 and 4. On 1 i got about 7.5 and on 3 I got about 8.4. i'm not sure how good of a reading I got but it seems to fit with my plug pull test in my original post. i also found a lot of the maintenance paperwork. The car had its head gaskets and a t- belt done recently.

Any idea on how to test the coil?

in-line spark tester. just put it between the wire and spark plug. have someone crank it over and you can check your coil and wires at the same time.

Your resistance seems pretty high on those wires....

I have a pdf on how to test the coil on my forester it is probably the same for your Legacy I can email it to you if you want it is rather long and drawn out but it tests every aspect of it.

Personally I would check the compression given the cars recent history and the appearance of oil on the plugs before going any further.

Update 2:

After checking the coil (thanks fllegacy) I found it to be good. The injectors seem to be doing what they are supposed to be doing. I put new plugs, new wires, and a new air filter (old one was black with dirt) in but to no real avail. I think i'm stuck here. It has spark and fuel, (I ran it for a min. and took the new plugs out after wards, only to find them covered in fuel).

What could be my gremlin here? Could it be timing related? it had a new timing belt put on <20k miles ago. I'm wondering if it maybe slipped a tooth or something.

I still need to run a good compression test. i did a quick one with the engine cold, plugs in, closed throttle and got about 90 on the good side, and around 30 on the bad side. That seems ominous to me but i'll need to run a good test to be sure. Thanks for all the help so far, the sooner I get this running good the better (my wife did not seem to think we needed another car, no matter how cheap it was)

90 seems a bit low to me for a good reading. Hopefully it goes up to minimum 148psi and normal reading of 185psi and no more than 7 psi difference between the four cylinders is what my fsm for 03 forester states.

At this point with the given info I think it is time to take the heads off and have a look see.

90 seems a bit low to me for a good reading. Hopefully it goes up to minimum 148psi and normal reading of 185psi and no more than 7 psi difference between the four cylinders is what my fsm for 03 forester states.

 

At this point with the given info I think it is time to take the heads off and have a look see.

That very well be the case here in a little bit. It is driving me nuts! I just checked over the mx records that came with it. head gasket and Timing belt were done at 115k at the dealer i bought it from. I would like to think that both those were done right, but who knows these days.

Does anyone know of a good write up for changing the timing belt? I don't think putting new gaskets on would be too hard, but I haven't done anything timing related in a long time.

update 3:

I finally ran a good compression test.

1- 90

2-175

3-90

4-173

that confirms my feeling that fuel and spark were not the problem. i pulled the timing belt cover today before work and gave it a quick glance. The belt is still on so I compared the notch location on the right side (looking at the engine, 2, 4) to the notch location on the left (1, 3) When the right was all lined up, the left was off by about an inch. That seems off to me. the haynes manual says (i think) that they are both supposed to lined up at the same time. Anyone have more experience with timing on the boxer engine that could offer their 2 cents?

It can take up to 258 revolutions of the engine for the marks to line up perfectly again. I can email you another pdf on the timing belt in a few minutes. At least you are getting somewhere now.

Thanks, I just opened up outlook and downloaded it. What exactly do you mean that it can take many revolutions for the marks to line up? Aren't they all three (left cam, right cam, and crankshaft notch) supposed to match up after every revolution?

the marks yes but not the marks on the belt one revolution of the engine doesn't equal one revolution of the timing belt.

ok, so all the marks should be aligned on the engine itself. That clears it up. I am trying to figure out the best way to tackle this issue. the timing belt is loose as all hell so I figure I could just mark the two sides that are good, take it off, line up the lefthand sprocket and then re install it. obviously turning it over a couple of times to check for valve impact. then hopefully starting it up. Does that sound like a decent action plan? I have what you sent me and i borrowed a haynes manual so I'll read it all over a couple of times before hand.

PROBLEM (SEEMINGLY) FIXED!!!

I ended up taking the Timing Belt off, and moving the rogue left cam back under the seam where it is supposed to be and put it all back together. I then said a quick prayer, crossed my fingers, and fired it up. It started fine, threw no codes, and warmed up without any problems. There is a little bit of knocking and whatnot, but i'll chock that up to maybe being from the ecu being reset. Anyway, i'm super pumped, I saved a bundle on a good car and learned a lot in the process. Hopefully it will continue to run fine and I'll be able to get a lot of use out of it.

thanks so much everyone for your help, especially FLlegacy, I really appreciate it.

Just to be safe when you get it nice and warm you should do another compression check to make sure the cylinders are in spec.

I am planning on it. I just picked up some new valve covers as I am going to check the clearances this weekend. There is a pretty decent knock/ping coming from the pass. side so I want to nip that in the bud if I can. other than that, I have been driving it (gently) for a day now and no problems, knock on wood.

Wow great job getting a good deal on a car and finding the issue!

One recommendation I'd give is to use a slightly thicker oil. It should help with the higher mileage motor. Maybe a 10w40 or if you live where it doesn't get too cold, a 20w50.

Wow great job getting a good deal on a car and finding the issue!

 

One recommendation I'd give is to use a slightly thicker oil. It should help with the higher mileage motor. Maybe a 10w40 or if you live where it doesn't get too cold, a 20w50.

Thanks for the recommendations, I will be changing the oil soon so I'll keep that it mind. I was really lucky in that when I bought it the trunk was full of papers (that I thought was trash) turned out to be all the mx records for the car. They had everything, even all oil changes, done at the dealer. That was nice, I really like knowing the history of vehicles I own.

On another note, I checked the valves today since I didn't have to work. They were all in spec so now I'm back to square one with the knock/tap. I will try some thicker oil next time, and also someone mentioned something called ceratune (sp?) from Germany. It was recommended to some other people on this forum to aid with piston slap. has anyone ever used this or have any knowledge of what it does? The car runs great now aside from the knock, and I would obviously love to keep it that way. I suppose i'll just have to do a little more research into the matter. Thanks again for all the help, I really appreciate it.

thats sweet you got the car running good, now that you have all this extra money you saved on getting a killer deal you should start to rebuild it, it seems like you like learning alot about the motor and there really is no better way then that. If i were you i would start with the heads nothing big no P&P or cams (unless you want, but then your going to want to go farther and its going to start costing some coin) just get some new valves and springs and clean the heads up some, then start with the "bottom end" (i guess you could call it that), maybe another 2 grand later and you could have a perfectly running motor with basically 0 on the clock.

hows the tranny??

thats sweet you got the car running good, now that you have all this extra money you saved on getting a killer deal you should start to rebuild it, it seems like you like learning alot about the motor and there really is no better way then that. If i were you i would start with the heads nothing big no P&P or cams (unless you want, but then your going to want to go farther and its going to start costing some coin) just get some new valves and springs and clean the heads up some, then start with the "bottom end" (i guess you could call it that), maybe another 2 grand later and you could have a perfectly running motor with basically 0 on the clock.

 

hows the tranny??

Ideally I would just keep my eyes peeled for a wrecked car with the same motor, get it cheap, rebuild it, and drop it in. The transmission is the 4eat and it runs just fine so far. I bought this to be a DD while I build up my 300zx, so I am hoping to put most of my extra income there, but who knows...

I'll try the oil thing today and i'll let you all know how it goes. Any opinions on what kind of oil the 2.5 likes? synthetic a good idea or no?