VS 5Litre not starting properly on LPG

[VTSSDUDE]

I have a VS 5 litre that when on LPG it has problem starting. It goes to start and then cuts out, sometimes if I pump the accelerator at the right time it will start. When it is warm, no problems, it almost dies but manages to keep going. Funny thing is, first time in morning, usually starts. If I leave it for a few hours, then start it, that's when the problem arises.
Also driving along, if I am coasting no foot on acclerator doing about 40kph and hit the accelerator I have a dead spot and the car chuffs and then goes. If I have the ute on Petrol, no problems. It feels like it is starving for fuel (LPG) with the dead spot no ignition.

Any ideas?

Spark plug leads are about 2 months old, and the plugs are about 6 months old.

Thanks,

 

[The1]

have you had it serviced, might be waxed up.

 

[VTSSDUDE]

Thanks, yes I have been thinking the same thing. I just heard that LPG specialist don't charge lightly to clean them out.
I might not have a choice though.

 

[Siggers86]

Check your coolant temp sensor, this has caused me some probs in the past with cold starts... Haven't had that problem on LPG but petrol, however it is possible...

But yeah could be as "The1" said above.

You could just switch it over to petrol a minute or so before you turn the car off, then start it on petrol, then switch over to LPG...

 

[VTSSDUDE]

The ute starts no problems on Petrol.
When I leave it on LPG. The LPG computer automatically starts it on petrol and switches it over to LPG usually does it within a second of starting. So I am not sure that maybe the idle mixture or mixture settings need to be adjusted on the converter as when I am on LPG it has a flat spot too. All symptoms of a gunked up convertor. As when it is warm it starts when the gunk is all loosened up, problem is at running temp the flat spot is still there.

 

[Siggers86]

Ahh right, didn't know it was a automatic switching Im not up to date on the new LPG systems clearly, yeah sounds to me if the car runs fine with no flat spots on petrol, its probably the converter... LPG services shouldn't be that much?

 

[Patti2912]

I've had a few issues with my VR running on duel fuel as well.
I've been explained the technicalities behind why it doesn't start very well on gas, but i can't remember exactly,
The main thing is that with most of the older duel systems, its recommended that you flick it back to petrol before turning it off.
Even though it starts on petrol, the gas mixer is still getting prepared to work and often struggles on ignition.
I always start mine on petrol, drive it for about a minute or two then switch over to gas, and vice versa when im parking.

In regards to the acceleration on gas, take it to an lpg mechanic, get a general service, sparks, leads, ask him if the mixer needs a clean out.
It will cost around the same as a general service and i can almost guarantee it will fix the problem.
Mine used to sputter, back fire, lose power spontaniously on acceleration ect until i had it serviced, now it runs almost exactly the same as it does on petrol, only has a slight delayed throttle response and obviously slightly less power which is to be expected on gas through a mixer.

If your car struggles to change onto gas (sputters for more than a few seconds) when you switch it over manually then it may be a solenoid problem as well, again, all things that your lpg mechanic can easily recognize and fix.

All the best with it bud