A few questions!

[Tazzy]

i) what is de-coking?

ii) whats it mean when a turbo spools up?

cheerz, im having a blonde day today!

[Aragorn]

i) over time carbon builds up on the surfaces inside the engine - de-coking is the removal of this carbon

ii) from idle to a value specific to each turbo the exhaust gases arent flowing fast enought to spin the turbo impller fast enough to create any boost to the engine - when the value is reached the turbo is said to spool up - ie begin to generate boost

[Tazzy]

wheer abouts does the carbon build up? after how many miles is it recommeneded? and how much does the procedure cost?

cheerz!

[Dicko]

all depends how you drive, what petrol you use, and how good/badly your engine fueling is setup. Its possible to get coked up in 500miles or less. A thin layer of coke throughout the head is actually needed for it to run properly. its when it builds up really thick on valves and parts od exhaust ports where it cuases problems. You can get pruducts such as 10k boost, or redex which are pretty cheap. but be careful using these on older engines. other option is to take the head off and give it an overhaul and decoke it then. best done when head gasket needs doing really!!
best tool is a dremmel with a brushing wheel on!!

[ade]

Build up of coke (carbon) also causes pinking noise when you accelerate - my old 1.2 ebgine used to do it - this apparantly is caused by carbopn getting hot and the fuel igniting before the spek fires causing the pink sound. Knacks the timing which fucks your acceleration.

I got quoted ?400 to decoke (said theyd put new valves and head gasket on at same time)

Ade

[Stuart]

a good way to decoke the engine is to get it up to operating temp and pour old brake fluid into the intake (through a carb etc), the shitte that will coume out its the fluid and coke. also a good way to dispose of brake fluid lol