Nasty flat spot on acceleration when cold

[deez]

Hi folks,

Get this horrible flat spot on the VS V6 when cold. If I use any more than 25% throttle when driving out of my driveway, the thing just doesn't go - if I keep the foot down, it coughs, splutters and may even produce a mild explosion back through the air pipe. Strangely, the problem goes away when the engine warms up.

The car runs dual-fuel and this only occurs on petrol. So is it a fuel pressure problem?

D

 

[Brett_jjj]

Try doing an error check.https://forums.justcommodores.com.au/threads/checking-error-codes-vr-vs-revised.22307It could be a dirty/blocked fuel filter ,or dodgey fuel pump,maybe even blocked/dirty injectors, especially if the fuel(petrol) system hasnt been used often enough.

 

[88GreenVN]

So if you start on gas the car runs fine and no flat spot? Cant be plugs or leads.

Would have to be on the fuel delivery side of things as the gas uses the same systems the fuel does and so would have the same flat spot......

 

[deez]

yeah, runs fine on gas. error check didn't produce any error codes but thx for the suggestion and agree it has probably been caused by not driving enough on petrol.

I'll try to approach this systematically to minimise cost - clean injectors, check, replace fuel filter, check, replace fuel pump. will let you know how it goes.

 

[chrisdoesitbetter]

might be worth checking your coolant temp sensor as well, although i think that sets a fault code

 

[ENV5]

Cant be pump, filter etc etc if the car doesnt do it when motor is warm can it?