VS - misfire under load

[Rhin0o8]

Hi Guys,

Car has a "splutter" under load, seemed fine reving in N and on take off its ok.
just when you need the power to overtake it will mis fire.
noticed a "clanging" from front passenger side under the Hood ( From Coil Pack )
immediate thought. stuffed coil??
Noticed water spray in the engine bay so I Changed top radiator hose after finding a split in the old one.

pretty sure it was still water damage. first checked was the injector rail. it looked dry.
check coils. all seem visibly ok ( did the test of removing 2 leads at a time to check where the spark goes.. all three coils's spark went to the next plug on its own coil, on each coil)

checked leads, found #4 was fried from the exhaust. So i replaced the leads...
not a job i want to do again!. haha sounds simple. just unplug and plug in the new ones. hmmm the alternator is in the way isnt it .. i obviously did it the hardest way possible with out removing the alternator..

tested in the carport. revved fine .. took it out on the road. still "splutters" and lack of power under load.

what else could be the cause of this. any ideas??

Thanks in advance

[VR_Acclaim]

dfi board mine done the same reved fine but under pressure it was a coil pack,,,,going well now

[hako]

As above...most probably the coil pack(s)....you can get them complete with the DFI module very cheap on Ebay. Run the engine in total darkness and rev the motor - look for sparks leaking.

[Rhin0o8]

thanks for the quick reply guys.

Checked the coil packs in darkness
saw leaking sparks
Ive got a spare one. but i looked further into the problem
took both leads off the coil pack and switched on the engine for a few seconds. spark when to from one plug to the other plug ONLY on the same coil pack
repeated this for all 3 coils

decided to investigate further thats when i found lead #4 was burnt halfway through from resting on the exhaust.
changed leads ran the engine again. I couldnt see any wayward spark

I can replace all 3 coils but im not sure thats the problem.

Is the DFI module different from the coils?
answered my own question.
thanks ill check on ebay and compare prices with my local auto shop

Not doing any damage driving it? only lack of power and worsening fuel economy?

[hako]

Fuels still cheap and it beats walking. Should be OK as long as you take it easy...maybe do some manual gearbox changing to keep the revs up so she doesn't labour and miss.

[VR_Acclaim]

i would change the coils first off as theres a 99 per cent chance its that,,,coils wont transfer spark between them they all try to spark when there spose even with out lead,

[RX25SE]

Did you check/replace the spark plugs?

Excessivly worn or large gap requires a higher secondary voltage to jump the gap. This can cause a miss under load and makes the coils work that much harder.

[Rhin0o8]

I swapped the coils into the VS from my VT and it ran like normal... eliminated a stuffed DFI module . thanks for that pointing out it could have been that, VR_Aclaim
Put the VS coils back in 1 by 1 . going for drives in between.

Found 1 stuffed coil so replaced it. running smooth again
Thanks Hako for the tips on how to drive it with a misfire/stuffed coil

all help and ideas are much appreciated

@ RX25SE - I will certainly replace spark plugs now also. as they are overdue.
means the car now will have new leads, new plugs . and ill put 3 good coils from my VT in the VS soon ( gives me an excuse to put the new ones in my VT )

[VR_Acclaim]

mine has the same now to lol and i found out my fuel reg is rooted so getting a new one thursday

[johnsy_vs]

Just to add i had same problem and it was a shift solenoid in the auto box , Manual now