CEL po303 road trip fun. dealer says "well you gotta problem"

[bustedbolt]

Hello all,

96 2.2 legacy brighton

 

I have an intermitent misfire #3 cylinder that I have chased for a year. It happens while going up a big hill at 70 in West Virginia and on decelleration when you take your foot off the gas.

Now the idle has turned waay lumpy on three cylinders i guess.

This all started last year when I was doing this same trip.

I don't really use my car that much as you might guess.

 

I have replaced plugs and wires with stock.

fuel filter and pcv then got "injector cleaning" at shop.

swapped with new coilpack.

 

It doesn't show up usually, so I think maybe it has been resolved. One CEL on a trip to boston. One on a trip to baltimore.

Now this trip is 500 miles to OHIO, and I get quite a few CELs while driving around town, I have avoided the uphill at 70mph stall by going 55 in the mountains.

 

I stopped at a dealer in bridgeport WVA to get an actual answer. They were very nice and took me in right away but..

 

They basically said yes you have got a problem.

your plugs and wires are good, you coilpack is good.

your compression is good at 125 pounds on #3.

moving the injector around did not migrate the CEL. your injectors are good.

next is your computer or something strange in your wiring but these are too expensive for us to check out as OEM new dealers.

 

So I am checking to hopefully find a junkyard computer to swap in...

 

and my questions are

-what ECUs are compatible with this 96 2.2 brighton?

-should i do a leakdown test on the valves? or have they eliminated this?

 

 

Give me your thoughts folks.. I am driving back saturday. Anyone got an extra ECU and could overnight it here?

 

Um also I should link http://www.ultimatesubaru.org/forum/showthread.php?t=74544 this thread where I first asked about this and got good replies earlier in the year. At that time I checked the injector contacts and moved the injectors then. but couldn't get the code to repeat so didn't really know what I was proving. Now since the code happens more often it was easier for the dealer to say the injectors are good.

 

thanks as always.

brian

[frag]

Compression good at 125 psi ?

I recently made a compression test on my engine cause it had a rough idle and because disconnecting the plug or injector on no 2 cyl did'nt make a big difference.

I had 195 psi on 1,3,4 and 120-5 on number 2.

Removal of the head showed a burnt exhaust valve on cyl 2.

So, maybe 125 psi is not such a good reading except if all the other cylinders show the same reading.

My .02$

(edit) I also have a 96 2.2L brighton.

[nipper]

We need the comprssion numbers on all 4 cylinders. If all 4 are 125 (which isnt great but OK) then its fine. If it is as i suspect, the others around 170 plus, and #3 at 125, there is your miss. Odds are its a valve, but you will have to do a wte/dry compreassion test on all 4 to find out.

 

nipper

[zstalker]

I agree with the above. 125 may or may not be good (soinds a little low to me), but a compression test is only really a good tool when you're looking at the difference between cylinders. If all your cylinders are right around 125, then that reading for #3 is ok....but if all the others, or even the other bank, are much higher, then you've found a little more clearly what the problem might be. I would lean towards a valve problem (burned, chipped, stuck, etc). With that result, get a leakdown test done, again on all 4 cylinders, to see more specifically what's failing.

The reason I'm suggesting those tests is because they can all be done with the motor in the car, cylinder heads still on, without tearing thigs apart, to minimize getting into really big labor charges just yet.

Another possibility I've run into is wiring. They switched the injector around, but did they make sure the #3 injector is getting a signal pulse in the first place? Maybe they did, I just want to make sure they're covering all the bases. If they can reach, try to switch the wires between #1 and 3 injectors. They'll fire at the wrong times, but the engine will still run pretty ok...that's a really good way to check the injector wiring...see if the misfire follows the wire, not just the injector itself.

good luck with that...some misfires can be a b!#ch to find...

~Erik~

[bustedbolt]

well thanks for the tips. I figgured the dealer would know what good compression was... gee.

 

I got my compression tester which was conveniently here in my dads garage and tested three cylinders quickly on a moderately warmed up car.

#3 @95:dead:

#1 @187

#2 @173

 

I am leaving the car with a known good independent subaru mechanic in OHIO here for the inevitable valve job. and getting a ride back home with friends.

 

Will update with the conclusions for the record.

officially a bummer at 131K

 

thanks again all.

 

brian

[x_25]

Thats a bummer. Although stuff like that can happen. My car ('99 OBW) had a camshaft seize at 118,000mi. That got it a new engine.

[WoodsWagon]

I've burned out exhaust valves on cyl 3 too. EJ22. Started with a miss climbing a long hill at WOT. Miss went away after idling the engine for a bit. Ran fine for a day, then came back with a vengance the next morning. Drove it for a while on 3cyls. Replaced head, burned a valve out of that head, same cyl. Drove for a few thousand miles on that engine running on 3. I unhooked the fuel injector for the cyl and just drove it like I stole it the whole time.

[unibrook]

Have you ruled out the front 02 sensor yet?

[nipper]

Have you ruled out the front 02 sensor yet?

 

A compression test has ruled that out.

 

 

nipper