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i need your help guys. I dont know why but im only running on three cylinders. heres what happened. Yesterday i decided to buy some oil to service the car today. So this morning i went out too the car and take it fora drive to warm up the oil abit. But when i started the car i noticed that it had the distinct sound of a modded wrx with alot of vibrations going on in the engine bay. Immediately i suspected a failed/disconnected coil pack - which i just replaced not long ago. So i opened the bonnet and fiddled with the coil packs. Started the engine again but the noise and vibration was still then, as the engine was running i disconnected each coil pack to see if any had failed. It turned out that coil pack in cylinder no.2 looked to be failed but as i didnt want to spend money on another coil already i switched it with another coil in a different cylinder. I started the engine again but with no luck cylinder no.2 still wouldnt fire no matter what coil i packed in there. So i tried disconnecting the injectors while it was running and again only cylinder no.2 would no responded. I recently had a compression test and all was around 160. What could the problem be, i havent tried fiddling with the wirning harness for the coil packs yet but im stumped. Its a long post but i didnt know how to explain it any better. Any help is very much appreciated.

Only other thing i can think of is what you mentioned at the end of you'r post, sounds like a fault along the wiring harness.

Is the bad idle the only symptom or is their smoke pouring out of the exhaust, does it drive/ missfire at a certain rpm?

prior to this it idled quite roughly with misfires here and there. It also stalls occassioanly when rapidly decreasing speed ie stopping at traffic lights. Now that i cant get spark/fire in the 2nd cylinder the engine visibly shakes. Someone please assure me that compression isnt down on this cylinder and its stuffed.

Ive had the worst luck since purchasing this car. Just when im going to change its oil this had to happen. As i mentioned before, engine shakes as it runs on only 3 cylinders. i think im going to have to get a compression test done again.

When I had a similar running in my RB20DET, turned out I had spat off a chunk of piston that, among other things, hit the end of the spark plug and closed the gap to nothing.

Pull the plugs, and check they're OK.

Check the usual first; Make sure you don't have any vacuum leeks for starters.

How old are the spark plugs? Maybe try a new set of plugs.

Go though and check the coils, look for burn marks / Cracks, anything that doesn’t look normal.

Do you know any one else that could lend you a working set of 4, that you could test?

Check the connectors on the Coils and check the connectors on the injectors?

Also what mods have been done to the car? Eg is it running standard injectors, Is it running an Aftermarket ECU?

If it’s still running on 3 cylinders after changing the plugs and a fresh set of coils, get a leek-down compression test preformed.

See how you go.

Ive recently replaced a cracked coil pack. Im sure none are faulty since i repalced the crakced coil pack as i have ran the engine on while cycling through the coils on each cylinder and only the 2nd cylinder that doesnt seem to respond even when i unplug the injector harness on that cylinder. As for plugs, I havent had the plugs changed since it was purchased although upon looking in the spark plug hole/cylinders there appear to have alot of build up of dust. I have a tool to remove the splug plug but havent been able to remove them yet as the extension isnt long enough.

The only mods that i have are fmic/full exhaust/bosch fuel pump/aftermarket radiator and bov - plumback. ecu and injectors im sure are standard along with anything else that hasnt been mentioned.

Simple and cheap to fix? matt, can you have a look at it for me as it would be very much appreciated.

Yeah sure mate, I can have a quick look if you'd like. What suburb are you in?

The first thing to do is pull the No2 plug and replace it. By the sounds of things it may well be as simple as a damaged plug (electrode and/or ceramic) either that or the plug is so badly fouled it won't fire.

I've got a whole stack of new BCPR6ES's and 7ES's, and even a set of six 8's, so if the SR20DET uses the same style plug then you don't even need to bring a plug :(

If it isn't the plug then we can go back over the coil and injector side of things. Don't stress that it's a internal engine issues just yet matey :D

im not stressing that its any internal damage to the engine although my post may come across that way. Its just that ive had one problem after the other since ive had it. I live in the northern suburbs - pooraka to be exact. thank you in advance as its very much appreciated. ideally i just want a third person's opinion and help.

Yeah I know what you mean re one problem after another... that's cars for you :(

I'm in Golden Grove (and Oakden) so it'll be easy enough to get to you, or you to me. Any time from about 7:30pm on during the week is fine with me.

I'll PM you :D

i still havent been able to get all cylinders firing but thanks for your matt especially in the condition and time that it was looked at. Although i was recommended to check the ignition starter (igniters) since these tend to fail and cause the coils not to spark. Hope this fixes it.

Sh$% man stop making me hyperventilate sorry to hear you've had drama's with it I never had half the problems you've had apart from blowing up gearboxes hopefully this is the end of the problems.

i hope so too mate. Its just these minor problems that keep creeping up now and then that is annoying. oh btw, ive heard that you are the new owner of a nice imported 4 dr line - congrats mate.

sil80 aint that fast anymore. the white r33 you saw when you were here blows its doors off now. hope you enjoy your line and active in these forums particulary the sa section.

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