OK this is driving me crazy and I'm *thiiiiis* close to starting to pull my hair out, so I appeal to you all and your overwhelming knowledge base for help.

 

A little background: Car is a '99 Outback EJ25, CEL for misfire on cyl3 and I think there was a "catalyst below efficiency threshold" or something like that in there at one point in time too. Stumbling was noticeable and seemed to be isolated to cyl3, could tell by unplugging injector and/or plug wire, but it had good spark and there was voltage at the injector plug (multimeter, no scope available.) swapping plug wires and injectors around did not make the misfire move. Finally car started burning lots of oil and 3 went completely dead, a leak down test gave lots of blowby into the crankcase and out the exhaust.

 

So yesterday I swap in a complete '95 EJ22 (dang that was easy!) and low and behold there is an intermittent miss that seems to be only on cyl #3! Sometimes it idles ok, sometimes not. sometimes the car accelerates normally, but most of the time it bogs down badly under load. Free revving the engine and opening the throttle quickly, it just gets really throaty and takes a moment for the RPMs to get up. Openign the throttle slowly it does just fine.

 

I've checked everywhere and can't find any vacuum leaks. I swapped the MAF with one from another car with no change to either vehicle. I did have to take the TPS from the old engine and put it on the new one, could lack of adjustment there be doing anything?

 

Seeming to be isolated to one cylinder even after a swap really has me stumped. Should I be looking at the ECU or wiring next?

 

Thanks guys, I really appreciate any help.

Did you ever replace the O2 sensor or check for a clogged cat converter?

 

What parts did you swap over from the other engine.

 

The miss is always on #3? Did you use new OE wires?

 

Are you sure this is an ignition miss and not a fuel injector miss?

Kinda sounds like a vacuum leak. Did you check the breather hoses and the PCV? Is the hose for the idle control motor firmly attached at both ends?

 

Did you do any work to the 22 before dropping it in? Timing belt? Separator plate?

Honestly I did not replace the O2 sensor, it was a code that would come and go, though obviously I should have, and that will be my next step. I swapped nothing from the old engine except the TPS, and did no work to the new engine. Both engines have OEM plug wires, and I've done the basics as far as moving components around to get the misfire to move, but it stays on #3 and I have no idea what kind of miss it is, other than it comes and it goes!

 

Any shadetree way to check the injector pulse?

 

Vacuum leak does keep nagging at the back of my head, I'm out of brake cleaner and need a break from this car so I think I'll head on down to the 'ol walmart and get some more

There is the ol rubber hose method. use a hose as a stethascope and listen to all four injectors. if they all sound the same we need to chase this down some more.

 

Check the grounds, clean them, maybe run a new one from the block to the body.

 

Check the MAF sensor as may also cause a miss.

 

Are you using the same coil pack?

What car did this engine come out of?

I thought the early EJ22 had to have some other stuff off the EJ25 in order to be swapped. I'm no expert on EJ swaps though so I may be wrong.

 

How about a compression test?

There is the ol rubber hose method. use a hose as a stethascope and listen to all four injectors. if they all sound the same we need to chase this down some more.

 

Check the grounds, clean them, maybe run a new one from the block to the body.

 

Check the MAF sensor as may also cause a miss.

 

Are you using the same coil pack?

 

I'll give the stethoscope trick a try. I swapped the MAF with one in my other car, no change to either car. It's a different coil pack, nothing was swapped between the two engines except the TPS. I'm getting good consistent spark but for the couple minutes it would take I suppose I should try swapping coils with my other car. I'll look into the grounds.

 

 

What car did this engine come out of?

I thought the early EJ22 had to have some other stuff off the EJ25 in order to be swapped. I'm no expert on EJ swaps though so I may be wrong.

 

How about a compression test?

 

There was one flavor of one year ('95 legacy w/ automatic trans) with an EJ22 that had both EGR and dual exhaust ports, and I just happened to stumble across one when I was wandering around the pick-n-pull friday I coulda been on the way to witness the birth of my first child and I wouldn't have left that yard until that engine was in the back of my truck!

 

Any shadetree way to check the injector pulse? [/quote

 

You can use a dwell meter (normally for adjusting ignition points) to measure and compare injector pulse widths.

 

I would check the TPS output,fuel pressure,compression and catalytic converter.

 

Try unplugging the O2 sensor too.

Edited December 6, 201015 yr by naru

Oh is that what a dwell meter does! I've wondered, but never had to work on anything with points so I guess it just never came up.

 

What kind of change should I expect to see with the O2 sensor unplugged? ...not necessarily running correctly but more consistent if the sensor is bad?

Oh is that what a dwell meter does! I've wondered, but never had to work on anything with points so I guess it just never came up.

 

What kind of change should I expect to see with the O2 sensor unplugged? ...not necessarily running correctly but more consistent if the sensor is bad?

 

Hopefully,a missing misfire,but,probably not much difference.

Yeah with the O2 unplugged it won't run right, but if it runs better than it does now the sensor is probably bad.

A while back I had this same issue (misfire cyl 4). I spent a week going through the exact same troubleshooting tests as you; compression, vacuum, spark, swapped coil packs, new plugs etc. I even went as far as to tear into the timing belt to see if it had skipped a tooth.

 

At any rate, after about a week I ended up throwing in the towel and taking it in. It ended up being a flakey fuel injector. Cost a little over 250 to fix and the car has ran great ever since.

 

You can read the original thread here which also details all my troubleshooting steps along the way.