Still pinking

[jonty1951]

I'm convinced that my engine has a build up of carbon, which is causing quite an audable pinking when warmed up.
I only cover about 5 miles a day in town traffic, and very rarely get to go for " blast" ( in fact the last time was a run to Barmouth last April !!).
Can anyone recommend a good additive / cleaner I can put in the fuel tank?
I also read on the inter web, that by spraying a fine water mist into the throttle body @ about 2000rpm, any carbon deposits will be blown out the combustion chambers and valves.
Anyone ever head of this one ?

John

[Jerry & Di]

Never heard of either of those - however: Water injection is a known tuning aid, but not for getting rid of carbon.

There are loads of "Redex" type internal engine cleaners which are mostly based on kerosene based solvents - nip down to Halfords and take your pick.

Nothing will beat whipping the head off to have a look, or even the plugs.

[jonty1951]

Thanks Jerry, what spark plugs should I choose ( it's a VVC) ?

John

[Jerry & Di]

Mar 2, 2012 4:59:39 GMT jonty1951 said:

Thanks Jerry, what spark plugs should I choose ( it's a VVC) ?

John

No idea , just sparky things. I just go with what's in the owner's handbook

[jonty1951]

Re my mentioning spraying a water mist into the intake to get rid of carbon build up's.
Just been reading more about it, and apparently it's a common practice ( if done carefully).
I've seen engines where the HG has failed, and the offending piston crowns and combustion chambers are spotless.
I assume the leaking coolant superheats to steam, and blasts the carbon build up's away.
Don't know whether I'd dare try it though !

John

[Jerry & Di]

When my headgasket went some time ago, I only ran it for about 45 minutes with the header tank pressure cap off, and when I stripped it down it was very clean inside.

I'm not sure if this has anything to do with it, but there is a danger of hydraulic locking of the cylinders if not careful.

Water vapour does have an effect on combustion efficiency however.