Over Revving On Tick Over.. Help Please

[Sophielou]

Recently had my head gasket fixed on my mk2 punto, having that done and clearing out all the air filter another problem has come up, it is majorly over revving on tick over, is believed to be the idle control value? had a few mechanics look at it n they stood their n scratched their heads n just suggested going to fiat, dad knowing a little about cars and through trial and error has unplugged this to prevent it over revving on tick over. now it occasionally cuts out when i take the revs off which i can handle for a short while but gets a bit annoying and quite dangerous when driving, anything i can do or get dad to do to fix it or does it mean having a new valve? have had nothing but problems with this car, but is my 1st car n i love it to bits, just drives me up the wall.
Help please?

xx

 

[fingers99]

You could try blowing through the valve with carb cleaner (most pound shops have it for, er, a pound).

Alternative possibilities are a vacuum leak (check all hoses) or a poor connection to the water temp sensor.

 

[sludgeguts]

Simples. When (you) removed the inlet manifold (or related items/something in that area) (you) didn't clean off all the old gasket.
Consequently, the engine is sucking air directly into the pots resulting in the over rev.

You can buy proprietry gasket cleaner that dissolves the old stuff, make sure to get it all off - and don't gouge the surfaces.
I'd also recommend using a bit of the gasket in a tube before putting on the new gasket - just in case!

It's an easy thing to do as there are times when it's not possible to get all the old gasket off easily but this is one of them times when patience really pays rewards.

There are ways of dropping the revs but not by the amount really needed - as you are finding out.