hey all, as u can tell by the title, cylinder 6 stopped working while i was at the shops. Thought it was a loose lead so i rechecked all leads and all corrosion. No problems. Swapped coil packs with another cylinder, and also swapped spark plug with another cylinder. Still cylinder 6 doesnt work. I can tell its 6 because as i remove the injector plug with all the others the revs drop, but with 6 they stay the same. I have tested the injector lead with a noid light and it works, and i have also checked the coil pack lead with a voltimeter and i got a full reading. I am now not sure wat it could be. The spark plug smells of fuel so im assuming the injector hasnt failed, but they are only about 40kms old anyway. I really dont know what else could consistantly cause cylinder 6 to fail. Any assistance would be greatly appreciated.
Before you eradicate spark as the culprit, test for actual spark, ie, while running have the spark plug in the coil and the thread resting against the plenum, it should spark noticably. A weak spark can be from PTU on the way out, or a coil pack buggered. Pot 6 is a bitch for access so don't worry about putting everything back on for this test, you'll be able to see just by cranking. Of the 3 culprits spark is the most likely. The other being fuel and compression.
Have you done an ECU diagnostic? If it comes up code 21, then it is likely that your PTU has failed for cylinder 6.
Didnt cylinder 6 always have problems with compression loss or something? could be way off but I thought I read something along those lines once. In hindsight probably should have read the whole thing then I would know more lol
They do....but, for it to go from "driving fine" to overnight not running on 6 pots, it screams electrical issues to me.
I had this same issue with No2 cylinder, my problem was one of the injector wires had backed out of the connector enough to not fire, may pay to give each wire a tug to see if they are inplace, other thing could be leaking injector o-ring flooding the plug. Eddie
There could be a 100 reasons, and everyone will post there own cylinder drop experience and what the cause ended up being, so your theory could well be right. The OP needs to do some more troubleshooting and start definitively ruling out simple common causes such as fuel and spark by looking at the connectors, injectors, coilpacks and PTU. If both of those gets firmly ruled out, then the more exotic reasons come into play, like low compression, leaking injector orings, leaking lower injector insulators, etc, etc, etc. If you can learn a good troubleshooting process, these sort of occurances become much easier to deal with.
