I have this what i can only describe as a misfire. The car when driving normally... 2-3k revs seems to jump like i have kangaroo pwtrol!!!

When i accelerate hard i sometimes get a bang and a puff of smoke (raw fuel?) from the exhaust. This does not always happen and sometimes the car is fine (not often i must admit)

these aside almost everytime i get high on boost 15-20 psi the car seems to be missing and holding back. Please help, i have had the plugs out and they look ok.

the car is running 21psi max on dark greens with a 330 bayjoo chip.

 

Hi, Try your rotor arm I've had similar problems on most of my cossie's. Also check your plug gaps (very important on these cars).

Hope this helps.

 

yeah first thing i'd look at are plugs try setting the gap to 0.7 mm and make sure you're using good quality ones i know of a few detonations on top speed runs on slightly worn plugs and we dont want that !

 

Ill check rotor arm today. I have had the plugs out and they looked ok but i must admit i didnt check the gaps . The plugs are NGK9's

CheeRS for the suggestions guys

 

also check your coil....maybe go for an group A coil (there cheap)
clean and fasten (real good)the connectors on the bulkhead....back/above the engine....these are a nightmare on 4wd saph...

close the gap even further to 6.5mm.....(but 0.7 first.. )

good luck

 

Aye first i would close the gaps and as above check the earths,clean em and refasten. It does sound very similiar to overboost though,have you increased the boost latly?

 

Rotor arm and cap seem ok, i have cleaned em up a bit. I have also cleaned and used electrical contact grease on the connectors on the bulkhead (3 of em??) I will gap the plugs. When you say the earths you mean the earths on the coil??