Help: My '02 is tossing misfire codes for all 4 cylinders

[johnceggleston]

that sound reasonable to me, but before you do , make sure it's the right size/type/ bulb. there is a horror story on here about a guy who installed the wrong bulb and smelled smoke, then a bunch of lights failed.

 

Which board is the CEL on? Someone told me I might be able to solder a new one on. Since it's just the little bulb thing that's clipped off (with a pliers or wire cutter).

[SilverSeraphim]

that sound reasonable to me, but before you do , make sure it's the right size/type/ bulb. there is a horror story on here about a guy who installed the wrong bulb and smelled smoke, then a bunch of lights failed.

 

Yeah, I'm not gonna try anything like that til I get this misfire sorted out. =]

[idosubaru]

if the wires were just cut, which they should be, then it should be a matter of just properly splicing them back together. i doubt they did much more than that.

 

need an update on what the new plugs, wires and such did first....all this talk about ideas and compression testing is really a waste of your time until you look at simple stuff and replace those ignition components.

[Downbound]

had a similar problem with my 99 forester..drive slow no problem , under a load, missing..took it to my local guy and turned out to be leaking valve cover gasket..He replaced plugs, wires (subaru parts), gasket and new plug tube seals for 350 Canadian, parts and labour...Works fine now..

[SilverSeraphim]

Ok. New plugs are in. We tested the wires and they didn't need to be replaced so I'm going to return those. Also, we changed the oil.

 

The problem is much better now, but it definately still there. I can drive mostly normally now, but it still starts to misfire if I'm driving hard. There is also still oil leaking around the plugs/boots.

 

The guys at Autozone said the same thing as you Downbound, and I actually have an extra valve cover gasket. I just don't know how to put it in. Is that something I can do or do I need to take it to a shop for that?

[SilverSeraphim]

Ok! My car is finally fixed. After I put the spark plugs in and drove around with them for a bit I read my codes and all the misfire codes were gone. The only code left was code P0172 Bank 1 Too Rich. I finally took it in to Subaru and they put a new O2 sensor in. Immediately my car stopped hard idling and drives perfectly now. =]

[Cougar]

Glad to hear you got it running well. Thanks for the update.

[unibrook]

Silver, I am very interested in how this all works out for you because my 2001 Forester 85k miles on it exhibits same symptoms. So far I have replaced plugs and tightened my valve cover bolts 1/8 turn. I will replace wires this weekend (and hey, maybe O2 sensor too after reading your report). The problem has been intermittant. Codes say misfire in cyl's 2&4. But I had no oil at all on cyl 2 plug boot.....had a fair bit on cyl 4 plug boot. Has your hesitation problem come back at all?

[unibrook]

Yep, mine turned out to be the front 02 sensor also. Here is my summary from a diff thread: I have a 2001 Forester L with 85k miles on it. I have been chasing an intermittent hesitation under load problem for the past year. Only occurred when engine was warm. The front 02 sensor had been replaced once at 40k miles. I suspected it again this time, but since the only codes thrown had been cyl's 2&4 misfire ( p0302 & p0304) I assumed it must be ignition related. So I replaced plugs and wires 8 months ago...no effect. Did the dollar bill test over exhaust pipe, it was fine. Misted the coil, no sparks. I mentally sort of ruled out the fuel filter since it only happened when the engine was warm. Finally, a week ago while cruising on hwy at 65 mph, I felt the hesitation again (I wasn't even accelerating this time) and a new code was thrown....p0172. AutoZone read it for me, I described the symptoms to the guy and asked if he thought it might be the front 02 sensor. He said, "absolutely." So I decided to replace it next. Cost me $100.75 incl tax for the oem part# 22791aa00a from Cityside Subaru. I asked the Parts guy there if his experience was that this model engine needed a new front 02 sensor every 40k miles. He said, "no, these sensors are good for 100k miles." Well, bullsnot on that. I replaced the new front 02 sensor in 1 hour reaching from the top over the passenger side of the engine using an adjustable wrench. Be sure to use the thread lube so you can get it out easily next time.....after another 40k miles. I took out the air channel assembly first for better access. That seems to be the fix. No further hesitation since. Car runs like new.