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Sorry but seeing as a lot of posts on this section refer to carb icing or throttle boddy icing I posted here...... If it shold be somewhere else well it'll get moved (ta mods)........

Its not cold air per se that causes the problem, its “almostâ€

bstardchild wrote: Shall I get my coat?

Nope, wanna cuppa?

Nice info there. How far is this going to effect injection? (I know it does but...)

is there any decent way around it?

DanW wrote:Nope, wanna cuppa?

Nice info there. How far is this going to effect injection? (I know it does but...)

is there any decent way around it?

It'll effect injection in exactly the same way but you won't get the evaporative effect of the fule coming out of the metering jet so it won't be as bad

With an air box it's never gonna be a problem - constant bleed of warm air from the manifold (I know it should shut off but it doesn't)

With a induction kit ice can form on the throttle butterfly just the same.

Airbox for winter?

erm you're wrong about the constant warm air as the flap is also opertaed by the induction vacuum, so that when you put your foot down, the engine will use cold air even if its cold because there is no induction vaccum to operate the flap.

this cause me loads of trouble on my mk2 over the years (coughing and spluttering to a halt on the motorway) due to carb icing.

since I've ditched the air temp flap and use a permanent warm feed during winter (for the last 2 years) I've had no carb icing

the effect with the spi's is nowhere near as bad as carbs though and the mpi engines dont seem to suffer from carb icing either

optima21 wrote:the mpi engines dont seem to suffer from carb icing either

Though mine does seem hesitant and need a tad more reving on occasions when it's freezing, not sure about other people.

optima21 wrote:erm you're wrong about the constant warm air as the flap is also opertaed by the induction vacuum, so that when you put your foot down, the engine will use cold air even if its cold because there is no induction vaccum to operate the flap.

Ahh thats when general car knowledge lets you down - most are operated on a bi-metalic stip and don't use vacuum - thanks for putting me right on this optima21

optima21 wrote:the effect with the spi's is nowhere near as bad as carbs though and the mpi engines dont seem to suffer from carb icing either

Injection engines don't suffer as badly agreed spi's can cos it's one big injector mounted in a car type body

mpi's shouldn't suffer from carb icing because the injectors are well down stream of the butterfly but I have experienced it on a six with mpi when I disconnected the throttle body heater