Air Leak '90 1.6 Gti (Sorry Large Pictures)

[Ramigojag 19 1 Cars]

I'd long suspected an air leak on my 205 after never quite managing to get the idle quite right and it stalled very easily whilst it was still warming up, finally managed to borrow a smoke tester, it showed a leak coming from the oil filler cap

 

 

 

You can just see the smoke starting to come out, it was worse than that, was just difficult to catch on camera because of the wind.

 

I attempted to seal it before buying a new one by fitting O-rings and a small amount of silicone sealant.

 

Borrowed a different smoke tester and it showed my attempted fix hadn't worked, but it also showed smoke pouring out from around the distributor cap which the first smoke tester hadn't shown. (the second smoke tester seemed to come out at a much higher pressure so im guessing thats why)

 

 

 

 

My question is from the above pictures where is the distributor supposed to seal from outside air? is it the actual cap? or is it as in the last picture, the small black part surround the shaft which would drive the rotor arm.

 

Or am i way off and the entire distributor is passed it.

 

Thanks

[jackherer 543]

Look underneath the distributor for the vacuum advance disc, you can just see it in your photos. The diaphragm inside must have split for induction air to be getting into the distributor. Take the tube off at the inlet manifold end and try sucking it, there should be resistance.

[Ramigojag 19 1 Cars]

Thanks for the reply, I'll have a test tonight.

 

is the diaphragm available as a separate part or is it integral to the dizzy?

[jackherer 543]

Vacuum advance modules are available separately, try a Bosch dealer or http://www.h-h-ignitionsolutions.co.uk/