Engine miss and 99 outback

solodon · #1 03-12-2015, 08:33 PM

Hi, recently my 94 SVX has developed an infrequent miss while sitting at a light. Like one cylinder didn't fire then runs fine for 5-10 seconds and will maybe do it again. Not every light just once in a while.

Friend totaled a 99 Legacy outback automatic AWD. I'm thinking the 4.44 is the gears in this but all references I've seen only go up to using 98 trans and diff. What's different or can the 99 be used?

Thanks, Don

Blacky · #2 03-13-2015, 05:20 AM

If it is a '99 with the SOHC engine it won't work. They changed over to the new engine and tranny in '99 and it's not easily compatible.

theflystyle · #3 03-13-2015, 05:37 AM

Could be the coils? I had similar issues and when I replaced mine (with better condition used ones) the problem disappeared.

solodon · #4 03-13-2015, 11:48 AM

The outback is a turbo and I'm not sure but that might be a 2.5.

solodon · #5 03-13-2015, 02:39 PM

The outback is a turbo and I'm not sure but that might be a 2.5.

solodon · #6 03-13-2015, 06:00 PM

Quote:

Originally Posted by theflystyle

Could be the coils? I had similar issues and when I replaced mine (with better condition used ones) the problem disappeared.

I'm sure I could find some used ones and if that took care of the problem that would be only OK as I'd have 6 coils and not know which one(s) are bad. I hate to fix what isn't broke.

theflystyle · #7 03-13-2015, 06:50 PM

Quote:

Originally Posted by solodon

I'm sure I could find some used ones and if that took care of the problem that would be only OK as I'd have 6 coils and not know which one(s) are bad. I hate to fix what isn't broke.

Check the resistant for each one. If you have the manuals its in the "Engine electrical system" one on page 17. It states:

measure the primary coil resistance. If the resistance is extremely low, this indicates the presence of a short-circuit

Specified resistance:
[Primary side] 0.68 - 0.83 Ohm

So check your coils and see which one could be bad. Its a free somewhat easy check. I would grab the manual as it explains how exactly to check the coil.

solodon · #8 03-13-2015, 09:58 PM

Thanks flystyle, after I'd posted I looked in the manual and found that information. I keep forgetting I have the manual. Also sometimes there are other ways to check things that people have learned that aren't in the book and easier. I'll start there but concerned that since it is so infrequent it might not show up with the ohmmeter.
Don

Blacky · #9 03-14-2015, 06:08 AM

I had a misfire which only showed up when the engine was hot and under load such as climbing a hill. It was one bad coil.
If you unplug one at a time you can easily find the bad one. If you unplug a good one the car will run worse. If you unplug a bad one the car will run the same.

solodon · #10 03-14-2015, 10:21 AM

Thanks Blacky. The miss is VERY infrequent so getting to duplicate the conditions is difficult. Seems I'd have to drive with a coil disconnected, running on 5 cylinders and see if while sitting at a light I get a miss. After a few days change which is disconnected and drive like that again until I never get a miss. When I had a coil go bad I disconnected an injector to find the bad coil. Seems it would be easier on the car to drive with an injector disconnected as I'd not be putting fuel into a cylinder that may not fire infrequently. Testing the coils electrically as described in the manual seems the way to go at this time.