the missus was on here way to work this morning when one of the NEW coils failed completly. she decided to drive it off the motorway on only four cylinders and about another km to the next service station. i've fitted a new coil but it's still only firing on four cylinders??? could it be possible that in the time between the coil failing and her finally stopping the engine that it has fouled the 2 plugs on the dead cylinders. the AA service tech who took 1hr to show up could only suggest revving the engine to warm it and unfoul the plugs which didn't work
Are you sure it was the coil in the first place and not the Module that the coils sit on, Have you washed your engine lately because if water gets between the colis and the module they can short out. How did you decide which coil was faulty or are you using the older style where all 3 are 1 unit and not separate. I too had a faulty coil a few years back and when i swapped my sons coils for mine his missed and mine didn't. I never sussed which was the faulty one as I replaced the 3 with MSD coils which at the time were only a couple of dollars extra each.
found the faulty coil using a multi meter, there should be about 7k ohm resistance across the 2 output towers, the 3rd coil was an open circuit. the coil that failed has only been on the car about 4 weeks, took it back and got a new one which tests ok but it still misses on the two cylinders. tried different spark plugs now, changed leads as well with the VN still no difference. so i suspect a faulty dfi module. got a new one coming tommorow lunch time but the guy at appco swears black and blue that if the module failed the engine wouldn't run full stop.
Well you did the right thing testing their resistance. Im interested to know. DFI module is a bit of an expensive one, hope it fixes your problem.
i had problems with my dfi module. It was shorting out on the bolt that is used to hold the connector in. The insulation had worn of the wiring and was shorting out on the bolt. I had this fixed and two weeks later the dfi module went (perhaps because of the shorting?? dunno). Anyway, check to make sure that the wiring going into the connector is not shorting out on the bolt that holds the connector into the dfi module. (the fix was to get a rubber cover for the bolt after the insulation had been repaired with heatshrink). I checked my coils that way to.
ps: my module was in the process of failing and the car would run, but only ever about 400m before the engine stalled again. The day it failed it was towed to holden to get fixed (i had no idea what was wrong) because there was no way i was going to be able to drive the car home at all.
yep, mine went home on a flat bed truck yesterday but i don't like paying holden hundreds of dollars when they don't really do a lot. i might as well just by a dfi module and spend the same.
this saga continues in my other thread about testing the dfi module, can you believe the new one i got from repco was faulty.:bang: it didn't work on my VN either. i'm thinking maybe the old mans VX station wagon is going to develop a miss fire this weekend very similar to my problem. then he can get it traded in for a new model maybe as it's a lease car anyways.:whistling http://forums.justcommodores.com.au/showthread.php?t=45476