Brand new problem (scary!)

NikFu S. · #1 05-12-2015, 10:53 AM

So I was driving home last night, car has been running really well for a little while with the occasional hesitation. I figured one of the coils was on its last legs.
So last night while driving I was cruising along, and I put the pedal down just a bit and I accelerated for a moment but quickly lost a lot of power. At this point it seemed as if I was missing a cylinder, but the last time I was missing a cylinder it ran a bit different. Last time it sounded like a 4-banger, this time it sounded like a motorcycle, and not a very fast one.

So I limp home, I'm barely able to keep it above 1500rpm and park it overnight.
This morning it won't start, cranks "OK" but I can tell it's having some kind of cylinder issue. Last time it had a bad coil I could still start it.
So I crank it for a few seconds and here is the scary part, it didn't even catch and yet I got the loudest backfire I have ever heard. My head still hurts.

Any ideas?

fasteract7 · #2 05-12-2015, 11:07 AM

Unburnt fuel pooled that got a spark..? A shot MAF maybe on the list. As you noted, a coil out shouldn't completely disable the motor where as a 100% gone MAF will. Some say that disconnecting the MAF will allow the car to start/run albeit poorly. My experience has been it will start but stall unless the accelerator pedal is pumped. Your night before experience mimics what I have had with my 3 MAF failures. Fuel regulator hose intact...?

92snowmachine · #3 05-12-2015, 01:04 PM

you may have jumped time. does it turn over really fast or buck the starter while you are cranking?

NikFu S. · #4 05-12-2015, 02:15 PM

I checked the timing last night. The marks seemed to line up alright as far as I can tell, though granted I couldn't get the cover under the upper rad hose completely off.

I'm not sure what you mean by buck the starter, but it's not turning as smoothly as it should.

NikFu S. · #5 05-12-2015, 04:26 PM

I just tried starting it with the maf unplugged and it didn't make any difference.

The churning felt a bit smoother than before but still a little wrong.

92snowmachine · #6 05-12-2015, 08:44 PM

bucking the starter is when it turns freely for a while and then slows down because the engine is out of time and fighting the starter. generally when you jump time it will crank fine for a second then fight back.

michael · #7 05-13-2015, 06:00 AM

Try pulling codes.

edren1 · #8 05-13-2015, 06:52 PM

Had the same problem. One of the wire harness plugs on the passenger side came loose. Cleaned plug and safety wired the plugs together so they don't come loose again.

NikFu S. · #9 05-13-2015, 08:43 PM

There is definitely some slight resistance when starting but it seems flatly distributed over time rather than getting slower or faster as the key is engaged.

I took it to the dealer today because I do not have the time to mess with it right now. They won't even get to look at it until Monday because only 1 person there is qualified to look at it.

I didn't think about trying to pull codes. Oh well.

I did look over the harnesses but didn't notice anything obvious. I suppose they are due for an inspection.

NikFu S. · #10 05-15-2015, 08:51 PM

Dealer is refusing to touch my car after looking at it. They did at least say that it sounds like the cams are out of time. No charge but I blew $70 towing it there and now I have to tow it back home.

92snowmachine · #11 05-16-2015, 07:58 AM

at least that's an easy fix. i replaced my belt in about 45 minutes. one of the easiest belts i have ever replaced.

NikFu S. · #12 05-16-2015, 12:15 PM

It wasn't a proper diagnosis, though. He just turned the key and called it a day.

I'm scouring the forum for similar experiences and I found this thread:

www.subaru-svx.net/forum/showthread.php?t=59411

It's a bit baffling to me that their problem was confirmed/circumvented by drilling holes into the exhaust.

My car has been running very rich and there is black soot on the inside of the exhaust tips, as well as my fuel economy has been pretty bad, but I chalked that up to the fact it was sitting for so long (2 years).

Thoughts?

92snowmachine · #13 05-16-2015, 01:12 PM

if our cat is plugged the exhaust can't move through it. drilling holes in front of the cat (or removing oxygen sensor would be a better move) will allow the exhaust to vent. if your car runs rich it will eventually kill your cat.

NikFu S. · #14 05-16-2015, 08:58 PM

Finally got it home, wouldn't start as usual. I pulled the O2s and got it to start 3 times. I put them back in and got it to start 2 times before parking it as not to make the neighbors cranky.

Something is still not quite right. It's a bit louder than usual and the sound it is making is very near to the motorcycle-y sound I heard the other day, though I didn't originally hear it from the outside.

I recorded the car from both ends in the hopes someone will recognize something.

https://youtu.be/pqWukDSq8SY

gwynethh · #15 05-17-2015, 05:37 AM

Quote:

Originally Posted by NikFu S.

Finally got it home, wouldn't start as usual. I pulled the O2s and got it to start 3 times. I put them back in and got it to start 2 times before parking it as not to make the neighbors cranky.

Something is still not quite right. It's a bit louder than usual and the sound it is making is very near to the motorcycle-y sound I heard the other day, though I didn't originally hear it from the outside.

I recorded the car from both ends in the hopes someone will recognize something.

https://youtu.be/pqWukDSq8SY

Pull the codes.