Eb4Prez
New Reader
3/5/15 3:01 p.m.
Picked up a low mileage (248K) wagon for my stepdaughter. Cold engine start up it has a miss for 2-3 seconds, then smooths out fine. Tho other night she re-started it and said it ran really rough and quit. I went up and tried to start it, hit once, then wouldn't start. Tried again 15min later and it fired right up, ran smooth. CEL showed mis-fire on cyl 1&2. Coil, or??
Coil should be simple enough to check via a simple spark test.
Remove the spark plug and ground the electrode. Crank the engine and look for a solid blue spark.
If not the coils then maybe start looking towards troubleshooting the fuel injectors.
Another aproach would be: Move the coils (or injectors) to cylinders #3 and #4, see if the misfire follows .
Maybe try just #1 or #2. I never like faults that report on two cylinders at the same time. For me it's almost always just been one component (not two).
The coilpack on a 96 EJ22 should just be wasted spark.
Move the plug wires around and see if the misfire moves, but there's not a lot you can do with the coilpack and still have the car run properly. The coil is pretty sturdy though so I wouldn't look at it for a primary cause. It takes a long time for those to exhibit wacky behaviour and even longer to die. If the plug wires have been bad for a long time that death can be accelerated.
The plug wires tend to get eaten up at the top because of the angle they have to fit inside the engine bay - I've seen some cars that were sparking from the plug wires to the engine bay and causing some very odd idling.
You may also want to check the MAF and the ribbed intake tubing running off from it - the ribs can often hide a tear in the plastic that isn't obvious when you're looking at it while installed in the engine bay.
When my MAF went bad in my '97 EJ22 (practically a completely different engine, but roughly the same sensor package) I had a series of issues where the car would refuse to idle at stoplights and just stall out unless I kept the revs up. My car wouldn't throw a spurious misfire when it happened, but I can see how it could happen.
Rough idling may be the idle control valve, which does get gummed up over the years but probably won't cause what you're describing.
Anecdotally, I've seen a few EJ22s with stuck injectors but not on cylinders 1 or 2, though it might be possible. I'd save that for later.
Eb4Prez
New Reader
3/5/15 7:00 p.m.
I just drove it to the grocery store, and after the initial 2second stumble, ran fine there and back. Plugs and wires were replaced last summer. When it warms up this weekend I'll break out the ohm meter and do some testing. Might just be the new 16yr old driver..
Small headgasket leak, dampens the spark plug, dries out and fires after a bit of airflow. Go stand behind the car when it fires up missing, and smell for burning antifreeze.
Eb4Prez
New Reader
3/5/15 8:42 p.m.
I will try that tomorrow, thanks!
1996 was well before the problematic head gasket era so hopefully you are fine there. I have seen them run weird when the timing belt skips a tooth; luckily 1996 is the last year of non-interference and the job is very easy if you have to end up doing it. I have also seen similar symptoms traced to a bad cam angle sensor...it was a problem on my '95, which had cold start issues similar to what you describe until I replaced it.
My Subaru experience would point to plug wires (use quality ones only) or a defective coil that may have a crack in it.
The EJ22s don't really have the same head gasket problems the EJ25 DOHC and SOHC engines do, for whatever reason (I assume a different supplier for different engine families).
They're pretty much the sturdiest motors you can get from a modernish Subaru perspective, they just leak oil like whoa and sometimes burn out an exhaust valve as you round the 300k mile mark.
Eb4Prez
New Reader
3/6/15 8:34 p.m.
It's been running fine the last few days (without a teenager driving it..). Going to pull, inspect, replace the plugs this weekend, check the coil and wires with an ohm meter, and do a compression check while I'm at it. Could it just have been the rapid outside temp drop/humidity thing? Hasn't thrown a CEL except the first night..hmmm
I worked on a 2001 2.5 with random misses. Cleaning up the ground wires,and adding star washers fixed the problem finally.
Eb4Prez
New Reader
3/8/15 6:12 p.m.
Plugs looked good, wires tested good, coil tested good. Cleaned up some corrosion on the coil end of #1 wire, and coil. Fired right up, ran smooth. Shut it off. Tried to restart to pull out of garage..no start..Quick check..we've got spark..shot of carb cleaner into TB..runs and quit. So appears to be fuel pump, any other suggestions before I pull it?
Give the fuel tank a whack with piece of wood, if it starts, fuel pump. Give the fuel filter a whack with the handle of a screwdriver, if it starts, fuel filter.
Go to Oreilly and rent a pressure tester kit. No sense in spending money and time on replacing a good part.
Eb4Prez
New Reader
3/8/15 7:01 p.m.
Ferris Bueller you're my hero! Didn't hear the pump cycle when I turned on the ignition, will give it a good whack! Didn't know tho big "O" rented those. Will have to try that too. I was a night manager there for 5yrs, and try to be faithful, but some of the people they have now is just ridiculous..but that's a WHOLE different thread...thanks guys
Eb4Prez
New Reader
3/10/15 7:55 p.m.
2hrs, 1 fuel pump and screen, 1 WIX fuel filter and 2 beers later she's up and running again! Should be good for another 248K miles. Thanks again everyone for your words of wisdom.