Extreme power loss, random stuttering.
 

I have what feels like an ignition problem.
It seems as if a coil is failing, but last time that happened it at least ran on 5 cylinders.
Now it seems to go between having full power and having none at all. It will seriously just lose all it's balls and sputter, unable to rev more than a few hundred or move.

I did the easiest thing today, replaced all the plugs, put some goop on them so the connections are good. Looked inside all the boots, didn't see anything strange.
Thursday when this issue began I popped the hood and did the injector plug check. At that time, it seemed that cyl. 1 was the culprit. Just before this it was sounding like an ej25t, so I assumed it was a spark issue.
Just now listening to it, there is a definite intermittent pop coming specifically from the odd (135) bank. This I think rules out the timing belt, which only has 14k on it anyway.
When I pulled the plugs tonight I noticed there seemed to be a lot of oil on them. These are the first plugs I put into the car back in 03. They were nearing the suggested maintenance interval anyway.

So I've also been losing a lot of oil lately. There is some slight leakage, I think most of it is from the odd bank valve cover... (ding, lightbulb).


Here is where I lack the technical know-how to continue solving this problem.

Is it possible an oil leak in the cylinders can cause this extremely rough running and popping? Is it more likely I'm losing two coils at once on the same side? Fuel pump?
The way it was running when I just pulled it into the garage and let it idle, was it would turn a few normally, pop, and repeat this in a fairly regular cycle. It wasn't the same as when coil 4 had went out. It's hard to describe because it really is just all over the place.


Here's the old plugs. (135246)
You can see 1 is more baked than the others. The original was like this, too. 4 seems to have a bit of rust on it. That was the first coil to go. It was replaced some months ago.

Re: Extreme power loss, random stuttering.
 

You may want to look at the cam sensor. Your symptoms sound very familiar to the issues the Florida SVX I picked up and drove home.

Crap, those are pricey.

Re: Extreme power loss, random stuttering.
 

They are the same as on other subarus of the era, just need to get the pigtail from whatever you pull it off of and just splice it in. The only difference is the connector. It's always and option. Otherwise, I'm sure there may be some people willing to sell one. Try to check your codes though.

Oh, another thing I thought of. With the Cam sensor dying, whenever it would drop to idle, it would die, both in gear as well as in P/N so another symptom to check before ruling that as the culprit. :)

Re: Extreme power loss, random stuttering.
 

It was dying occasionally at idle, like it would just rev lower and lower until it just kind of sputtered out.
When I gave it gas, sometimes go, something nothing at all.

I had to tow it home Thursday because after it died it wouldn't even start back up. Didn't even catch once the entire night. Tonight was the first time it caught and started since Thursday afternoon.

Re: Extreme power loss, random stuttering.
 

Yep, sounds very familiar... :o
Try taking the Cam sensor off, clean up the contacts and see if it helps at all. It may get you by with it for some time or do absolutely nothing. At least its real easy to get to if it turns out to be the culprit...

Re: Extreme power loss, random stuttering.
 

Pulled the codes, 37 and 14, but that may be because I pulled the injector plug while it ran. The O2, yeah I can see why I'd get that.
I'm not convinced the injector is bad. That alone shouldn't stop the engine from starting, should it?

I'm wondering if maybe the ignition control module is bad. I'd think with two cam sensors I'd get at least one bank firing*, or does it not work that way? :confused: Fuel is dumping so I'm pretty convinced it's the ICM or crank angle, maaayyybbbe coil 1...

*Ok it seems there are two crank sensors and one cam sensor. I had that reversed. I thought that second cam sensor was oddly positioned... I wonder why SubaruParts wants me to buy two at once...

Re: Extreme power loss, random stuttering.
 

I'm looking through a lot of "starting trouble" threads and it seems there is a high prevalence of code 37 among them...

Also, now thinking about it, I usually do hear a gurgle when I turn the key on, this last time I don't remember a gurgle. Wishing I didn't drive it into work today, because that's where it's stuck right now. Argh, lol.

Re: Extreme power loss, random stuttering.
 

The sensor used as the "cam sensor" is the same type of sensor that is used as one of the crank sensors. There is only a cam sensor on the US driver side bank.

Yes, it threw the code for the injector because it was unplugged.( I am assuming that you mean the electrical plug for it?) and probably then caused the o2 sensor to get thrown out of whack...

The cam sensor being bad never caused a no start for me at all.
Try unplugging the MAF sensor and seeing if it will start/run normally at all or if it changes anything. On mine, when I unplugged the MAF sensor, it ran and drove completely normal. I assume it went into an open loop running condition or some other standard set of a/f ratio...


Hmm this just caught my attention combined with all of your symptoms, talking about "gurgling", what do you mean? normally the fuel pump should gurgle when you first turn the key. Perhaps that is starting to die on you?

Would love to unplug the maf but it's a z32 and has me a bit baffled. :rolleyes:

Re: Extreme power loss, random stuttering.
 

Bought a new cam.p.s. which just arrived. Figured I would need one eventually. Will find out if this fixes it. If not... I'm going to pull an ICM from someone here.

Re: Extreme power loss, random stuttering.
 

No effect. Unplugging the maf also does nothing.
Definitely not hearing a fuel gargle. Since I have a Walbro I may attempt putting that in while I wait for whatever is next.
Any reason I shouldn't do this with half a tank of fuel? :rolleyes:

Re: Extreme power loss, random stuttering.
 

Really? It sounds like it could be a faulty MAF...

Re: Extreme power loss, random stuttering.
 

Yeah I just unplugged and tried to start it, no change.
I'm going to try to attack the fp relay tomorrow. Kinda difficult with the car sitting at work. Cold as **** outside and very dark.

Re: Extreme power loss, random stuttering.
 

There is less chance of explosion if the tank is full.
Gas tank fires are bad enough, but a gas tank explosion will just ruin your day!:(