I've been getting this code very frequently now and my car is now running like crap with the following symptoms. (~45,000 miles currently on the car)

- Real low power
- Cyl#4 misfiring constantly
- Some blue smoke on startup
- Rough Idle
- Backfires a lot, especially on rev

I've replaced all 4 spark plugs (original plugs came out and looked great). I also replaced the coil pack on cyl#4, and performed a reset on the ECU, but have still had the same problems.

I was told to check the injectors next. Has anyone else had this problem before? Any other ideas of things to check?

I've also had a lot of oil spray out of my boost controller and my blow-off valve, is that normal?


ugh

Mike

Well low oil can produce and engine knock which is the piston hitting the valves which then damage the valves and cause a missfire... So watch your oil level.

If you have done, plugs, wire and coil and still have that #4 missfire... an injector would be the next thing on the list.

What you might want to try is switch that #4 injector with say... #2 injector and see if the missfire follows the injector. If it does then you know what the problem is. If it remains... well then its something else.

How's the tune? Are you running the UTEC or another EM?

When did this first happen? Did you do any new mods and then have it happen? There is an air line that has popped off on my car that has caused cylinder misfires. Maybe, check the lines for air leaks.

Well low oil can produce and engine knock which is the piston hitting the valves which then damage the valves and cause a missfire... So watch your oil level.

If you have done, plugs, wire and coil and still have that #4 missfire... an injector would be the next thing on the list.

What you might want to try is switch that #4 injector with say... #2 injector and see if the missfire follows the injector. If it does then you know what the problem is. If it remains... well then its something else.
yeah that's the same thing the happenen to me, but the way it got that way is a different story. :D

My car's #2 cylinder has been misfiring off and on for a while and a new fuel injector took care of the problem.

I guess I'll try an injector swap this weekend. Anyone have a stock injector or a larger set I could buy just in case this proves to be the problem?

Well low oil can produce and engine knock which is the piston hitting the valves which then damage the valves and cause a missfire... So watch your oil level.
There is NO WAY that low oil level is going to turn the EJ20 into an interference motor. Search "engine knock" to find out the real cause of knock. Besides, Konvict's problem is misfire, not knock. Let's not raise red flags on imaginary issues.

If you have done, plugs, wire and coil and still have that #4 missfire... an injector would be the next thing on the list.
What you might want to try is switch that #4 injector with say... #2 injector and see if the missfire follows the injector.
However this IS good advice (except that the Subaru does not have plug wires). I assume that you did the part swapping that we talked about before replacing that #4 coil pack -didn't you? If the problem followed the coil pack you replaced it, right? Do you still have the old coil pack? A coil pack is essentially a step-up transformer -it has primary and secondary windings. I'm without a manual at the moment, but I can suggest that you compare the resistance of each of the bad pack's windings with another (good) coil pack. They should be within 5-10% of each other. Sometimes a coil will short itself to ground only under very specific circumstances -high heat, etc. Testing the resistance of each winding and comparing them to known good values will find a fault that's been 'hiding' from you.
Also, what did the old plugs look like? The new "hot" motors make reading spark plugs kinda obsolete, but I still find it useful. BTW, Iridium is not really that great of a conductor -it is not the be-all-end-all of sparking materials. The reason OEMs use it is because they last a long time. Modern motors are expected/required to last 100k miles before a tune up. If you eliminate the cap/rotor, coil and sparkplug wires, all you have left is the plugs. Copper plugs last around 50k miles. So, they replaced them with Iridiums, which will go 100k without a problem (barring any physical damage). If you want the best conductor, go with silver. Since silvers are kinda hard to come by, go with copper (after all, almost every electrical conductor in your house/car/boat is made of copper). 100 billion miles of wire can't be wrong.
I'm also going to assume that at your level of tune, you're running "Pinks". If not, you should be. Swap -no not replace- to troubleshoot the injectors. I don't think that this'll be a fix though.

Since you're burning/losing oil, my money's on a piston ring. What kind of boost are you running? Some people have noted that cylinder 4 runs a little lean/hot. Big boost +big explosion = broken ring land. Leaky ring = fouled plug. Fouled plug means misfire, unburnt fuel, O2 sensor wackiness, backfire, and the list goes on.

If you really want to get to the heart of the problem, take it in and have a compression check done on each of the cylinders. A busted ring land will show up as low (compared to the other cylinders).

However this IS good advice (except that the Subaru does not have plug wires).

Well actually the non turbo subaru does. I've had them replaced before for customers. But you are correct I believe the turbo does not have wires because I can't get a part number for them.

Check Konvict's Vehicle info looks like he has a 2003 WRX. He also has a UTEC.

I'd look at everything else before I go with injectors or rings.

Winslow

you are just throwing parts at it until you read the "freeze frame" data, which is an ecu snapshot taken when the code sets. this will tell you if it's ignition or fuel or mechanical missfire. the freeze frame can be read with most decent obdII scanners.

get the freeze frame, post it up, and i'll tell you what the problem is.

yes, just ask jerry! lol. :D

Jerry, do you have to reset it, and run it with an obdII scanner to get this "freeze frame". Or is it stored along with the code in the ECU?


JP

now my experience with scanners is with the Tech II that GM uses. I used those all the time when I worked for them and I know that when a code is set and the cel is on, the freeze frame data is also stored at the same time. Basicly it takes a photograph of all the readings of everything when a code is set. However I have no idea about the over the counter at auto store scanners or even the one Subaru uses. I would imagine it should have that info along with the code.

But I'm sure Jerry knows for sure.

Note: Never buy a obdii scanner at walmart. It just plain didn't work.

I have an Actron scanner here in Fairbanks -I usually keep it in my truck.

It'll give you code history, but no "freeze frame" data.

Your symptoms point to burning oil. There's only one thing that causes that. Get the compression check done.

When you do find and fix your problem, take out that UTEC and throw it in the trunk. Just my $.02.

After testing the plug and the coil pack for spark (worked fine), I did a compression test on cyl#4. Only got about 70lbs of pressure. Haven't tested the rest yet, but will get that done soon. So I'm thinking it may possibly be burned valves, which i've read can cause excessive blowby (which I have), oil on the spark plug, oil in the exhaust (have both of those too). The other test people mentioned here on nasioc was to take off the oil cap and rev the throttle by hand and see if it puffs smoke.

Anyone familiar with replacing valves (cost/labor)? Anyone want to? Is it worth fixing this motor?

One more thing, I talked to a mechanic, and he said he doesn't think it's a burned valve because he doesn't think there would be any pressure at all in the compression test. So he said it could be a worn cam lobe or somethin like that.


?????????


Mike

sounds like piston/ring problem, not valves. detonation = broken ring landing.

should have done a leak down, that will tell where the air is going.

70 sounds low. You should be seeing around twice that. Compression tests aren't worth much. I'd consider doing a leak down check.

edit: yeah, what Jerry said.

Winslow