Mk3 16v overun probs.

[tshirt2k]

Hi all, After searching many threads on starting probs etc, most things have been changed, ie : relays, coil, distributor cap, temp senders etc.

I think i have narrowed it down to being something to do with overrun and/or throttle switch.

When off the throttle and slowing down to a junction say off a motorway, as i go to pull away again, the car seems to misfire from idle to about 2.5k. It can happen at slower speeds also. It seems that there may be too much fuel and its bogging down.
This may be why there is a bad smell of fuel out the exhaust when starting from cold.

It seems to be better if when slowing down i pop it into neutral when slowing down. slowing down in gear is definitely worse, but it doesn't happen all the time

Has anyone had this problem ?? and does anyone know how to test throttle switch and potentiometer ie what voltages on pins etc?

thanks

[tshirt2k]

partly cured, cleaned throttle body a bit and isv with carb cleaner. will prob dismantle it and clean it better.

[tshirt2k]

Problem Cured.
After removing throttle body and thoroughly cleaning. Put it back on but was still misfiring and hesitant on pull off and when blipping throttle from idle. Decided to change all the visible vacuum hoses on the engine with new 3mm id silicone hose.

This has transformed the car, throttle response is better along with more power. Idle is better too and easier starting. 

Although original tube was intact apart from slight fraying, it was quite soft and was possibly collapsing by vacuum and engine movement.