'96 EJ25D Cyl. 2 Misfire

[Numbchux]

'96 Legacy Outback Wagon, 4EAT, DOHC EJ25D, 126k miles.

mysterious rough-running, stumbling, etc. only while under load (not necessarily driving, but never does it in park or neutral). noticeably aggravated by the A/C compressor (symptoms come and go as the compressor cycles on and off), although sometimes the symptoms appear independent of the A/C.

occasionally the CEL will flash for a minute (indicating misfire....), plug in the code reader, and it's always cyl. 2.

quick visual inspection of the engine bay doesn't reveal any noticeable problems.


Thoughts?!

[ChesterKV]

Could be a bad spark plug (gapped correctly?)....... bad or clogged injector.........bad ignition wire..........

Try swapping # 2 and # 4 ignition wires to see if the problem follows the wire. If it does, then it's the wire. Check all connections for looseness/corrosion, etc.

[Numbchux]

today I swapped #2 and #4 plug wires. and pumped some SeaFoam through it. with zero change. I bought some new NGK plugs, and have another coil and igniter (although I'm hesitant to suspect either, as I bet the wasted spark design would cause a misfire on #4 as well) to try tomorrow. I will also try to get my hands on a compression tester while I'm in there (god I hope it's not a burnt valve ).

[ChesterKV]

today I swapped #2 and #4 plug wires. and pumped some SeaFoam through it. with zero change. I bought some new NGK plugs, and have another coil and igniter (although I'm hesitant to suspect either, as I bet the wasted spark design would cause a misfire on #4 as well) to try tomorrow. I will also try to get my hands on a compression tester while I'm in there (god I hope it's not a burnt valve ).

Yeah, hope it's not a valve or anything. It's good that you have a spare coil and igniter so you can avoid chasing ghosts. If that doesn't work and the compression check shows a healthy no.2 cylinder I would suspect the injector is clogged or damaged. Seafoam isn't going to repair a physically damaged injector and if the clog is something larger than minute deposits then it isn't going to completely eliminate it either.

Have you checked your grounds? It's worth taking a look.

Good luck,

Chester

[Mr.Pessimist]

Yesterday I got the infamous CEL on my Baja. I took it into the auto parts store and I got "misfire cyl. 4"

I just spent all day trying to find out the problem to no avail. From what I've read it could be:

Bad cable
Bad spark plug
O2 sensor
Bad/clogged injector
piston ring issue (compression)
piston issue (compression)
knock sensor

I pulled the plug and inspected. It checks out. I see no signs of abnormal wear (just replaced them 3k miles ago). The cable seemed to not seat very well on the plug for that cylinder but after messing with it for a while I'm pretty sure that's not the issue. I did swap cables (#2 to #4 and vice versa) with no change in problem.

I'm not sure what to do at this point before I take it into the shop and spend a ton of money having them find the problem. I don't really have the tools (i.e. compression checker) and I could check the injector with a meter but that won't tell me if its clogged.

I have a friend with a 2nd gen Outback coming over so I can swap one of his ignition cables in, but that's the best I can do for now.

I suppose I can check the plug for spark. Can the engine run with a spark plug pulled out?

Above all, I can tell you all for certain that there's misfiring going on. The engine runs really rough at idle but seems to do fine a higher RPMs. One MAJOR concern of mine is the fact that I've been dealing with intermittent engine knock for the past couple years. It was never consistant but would occur during hot days combined with heavy engine load (climbing a hill) at certain RPMs. So my bigggest worry,with that in mind, is a piston damage issue where I've lost compression.

I've read almost every NASIOC posting about this (seems like a lot of people have this issue) and no one has been able to completely come to a conclusion. This is of course because there are so many things that would cause it.

[Numbchux]

Oh....I forgot to update this....


turned out to be a plug. cyls 1, 2 & 3 had champion plugs in them, and #4 had an NGK that was probably original, and still running better than the champion in #2....


sooooo.....what kind of plugs did you use? I've had brand-new Autolites give me problems from day 1....

also, a compression tester costs about $30 from your average auto parts store.....money well spent....

[evolutionmovement]

NGK.

[Mr.Pessimist]

I'm running the recommended NGK plugs just as I had before. I've been thinking about it more and it seems like its a fuel injector issue. The car has always run a little rough and I've had the knock issue regardless if I was using the old plugs then or the new ones now. I'm looking at things that would cause problems over an extended period of time that would gradually get worse. Maybe the wires, but more so I think it would be injector issues. Another hint: If the Baja has been sitting for a while (like a week) when I start it up it runs rougher than normal. In fact, I just got back from a week trip last month where the Baja had been sitting and when I started it the engine was shaking the whole car (misfiring) but no CEL. Could a lean condition (bad injector) also create the engine knock I've noticed before? I can't help but think the two are related.

[ciper]

NGK V-POWER FTW

[ChesterKV]

In one case, I had a bad #3 fuel injector that would not fire at idle but would be fine when giving it some throttle.... weird but that's what happened. The symptoms were a rough idle; the engine was actually only running on three cylinders at idle. After turning off the engine the exhaust smelled like rotten eggs. When I replaced the injector, the rough idle disappeared and the rotten smell went away.

Also... big second for the NGK V-Power..... copper all the way.

http://www.ngksparkplugs.com/products/c ... vpower.asp




- Chester