P38 running at 11 mpg and not working on gas

My P38 4.0 has something up with it, symptoms as follows -

Won't always idle correctly, sometimes its fine, sometimes it runs and stalls (takes 5 or 6 starts to get it running right

It won't run on LPG anymore

It's averaging 11 mpg

Any thoughts?

Thanks

Just some thoughts below, not an exhaustive list,but try these after a service and a plug in to a diagnostic, think about:
If it's old enough, fuel filter
If it's younger fuel pump
Maf sensor
O2 sensors
As for the LPG it could be any number of things, the systems do require a service, filters and the like, as it's generally a system that piggy backs on your ignition circuit it may be causing a problem.
So there's quite a few options, I'd definitely get it plugged in before I spent any money on parts.
Hope this helps

Em, buy a diesel? wasp nest prodded.

tomcat59alan said:

Em, buy a diesel? wasp nest prodded.

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You are a little tinker at times.

Won't always idle correctly, sometimes its fine, sometimes it runs and stalls (takes 5 or 6 starts to get it running right

It won't run on LPG anymore

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So, to get this straight, it wont run properly on petrol and wont run at all on LPG?

Sounds like something is interfering with its desire to work. MAF, O2 sensors.. blocked injectors???

LPG has a higher calorific value than petrol, so if it works on petrol it should be working on gas. What LPG system is it.. single/multi point.. when was the LPG filter last changed ?

They don't run well on LPG when it has all leaked away.

indeed Keith. both petrol and lpg seems to leak away too often... through the exhaust manifold !

ukadamwest said:

indeed Keith. both petrol and lpg seems to leak away too often... through the exhaust manifold !

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Diesel leaks at a much slower rate

Diesel leaks at a much slower rate

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but it sounds like a tractor

ukadamwest said:

So, to get this straight, it wont run properly on petrol and wont run at all on LPG?

Sounds like something is interfering with its desire to work. MAF, O2 sensors.. blocked injectors???

LPG has a higher calorific value than petrol, so if it works on petrol it should be working on gas. What LPG system is it.. single/multi point.. when was the LPG filter last changed ?

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LPG has lower calorific value than petrol not not higher.

Datatek said:

Diesel leaks at a much slower rate

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Also drives at a much slower rate

dove said:

Also drives at a much slower rate

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In your dreams

dove said:

Also drives at a much slower rate

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Deluded, mind you diesel will probably wax up in Scottyland due to the cold.