Bad miss/pop on TB42 duel fuel..

[BrentE]

G'day, i have recently just got this bad miss from my TB42.. It's a loud pop with a miss around carby/driver floor area, seems like the car is starving for fuel then gets a heap of it..? It's so bad it jolts car, and loses power for a split second. It's random when it does this pop noise.. usually it happens after the cars been going for more then 20mins, it's not very often but has happened 5 times in 1-2 hour's once..

Could this be carby problem? Because i did get dirt inside carby somehow 4wding. Also it does this on both petrol and LPG.

[hiy6o]

ignition leads or spark plugs , the loud pop is a backfire . (maybe ignition points if it has them)

[BrentE]

Spark plugs have been done about 1000km's ago and distributor has been done around 500km's ago, the ignition leads do look fairly old so that could be problem. It's just weird how its doing it on both petrol and LPG.

[351ciofgrunt]

Had this problem recently, turned out to be ignition leads, don't forget the coil to dizzy lead

[RN]

I have a dual fuel TB4.2

I found that mine began backfiring on throttle off, sometimes when changing gears. I eliminated it by pulling the high tension lead out of the coil and found a build up of gunk inside the coil neck which was causing poor connectivity.

[hiy6o]

I'd go with the leads , they may have damaged the inner core when removed for plugs to be done (they get brittle with heat and age).

[BadMav]

Did you replace the condenser as well when you did the dizzy? $17.50 genuine from nissan.

[BrentE]

Did you replace the condenser as well when you did the dizzy? $17.50 genuine from nissan.

Nah i didn't mate, what part is the condenser?
Are bosh leads the ones too go with? I have heard these are the go for TB42's BOSCH Super Sport Inductive Core Ignition Leads (B6104i).

[BadMav]

It's screwed to the front side of the dizzy underneath vacuum advance diaphragm (under the top radiator hose). It looks like a little barrel about 2.5 cms long and as round as a 5c coin with the dizzy wires going into it. Bit fiddly to get to, try not to round out the screw head, you'll need a short stubby screwdriver.

looks like this but with longer wires...



Long term, look at getting yourself the pertronics elec igntion insert for the dizzy, no condenser and no points to fluff about with. Gets rid of the 1200rpm miss too.

I only have povo 'Top Gun' silicone leads on mine and it's fine. Unless you're running big turbo boost or big revs/high horsepower, regular leads are fine.

[BrentE]

Cheers mate thats really helpful, i've been looking at going petronix ignition for awhile so i may just get around to buying one. I have that 1200rpm miss lol car was soo much better when i put new spark plugs in NGK BP6ES and new dizzy though.