Fixed Idle Issue...Now car is skipping!! :(

[JohnL]

JohnL thanks for your reply, I think im on the same steps as you. i didnt actually make a gasket but i thought if there may be a leak in the IACV then i probably should ensure that its not there. soo i used some silicone gasket maker. Put that on and waited bout 5-10 before i started the car. the gasket GOO has worked for me before in similar situtions so that would be the same effect as your Motor cardboard idea (but yeh i know what u meen by the cardboard, used that stuff before).

But i think yeh it must be something with the IACV...thats really the only thing changing when i plug and unplug the Sensor from it. Going to take it to my uncles (mechanic) tomorrow and ill pick up another IACV from a wrecker on the way and give that to him.

I'm not sure I follow what you mean about the "silicone gasket maker", you need to block off some substantial holes (IACV ports), and I'd have thought that even with a few minutes to cure (which would take a fair while longer with a big slug of silicone) the silicone goo would tend to get 'sucked' into either the plenum, the IACV, or both? If you sucked it into the IACV then you could bung it ip pretty comprehensively I suspect...

Do you mean you deliberately bunged up the IACV by filling it with goo?!

Just a thought. Have you checked the rubber gasket between the IACV and plenum? It could have a leak either to atmosphere around the edge, or from port to port (i.e. air could pass between one port and the other without being metered through the IACV).

Personally I won't let silicone gasket goo anywhere near my engine. I'm told that if it gets into the combustion chamber that it's burnt gasses can 'poison' the cat converter and impair it's function or even make it not work at all. From personal experience I know that it can get 'loose' inside the engine, not a good thing, though in a modern engine it would get caught by the oil filter before doing any damage... probably. It might possibly block the oil pump ports if there was enough of it...

When I used to work in a motor museum we had some come loose inside the engine of a Bugatti Type 35B, caused some issues as the oil filter was non existant (we didn't put the silicone in there, it was somebody who worked on the car before us).

My favourite gasket goos are; 'Aviation Gasket No3', or 'Blue Hylomar', both are 'non-hardening' and dissolve if they get into the oil but not if they stay in place at the gasket. Silicone is fine for gearboxes...