Audi 200t: starting and fueling problems...

[gerard]

Hi!

Need to help a friend with a 1991 200 (MC engine). Had some starting 
problem 'cos car was standing forever and seems previous owner shoved in 
some other distributor. Vehicle now has spark, misfires a bit, but can be 
started and run.

Problem is the actual starting. I am not 100% certain about the operation of 
the "lambda valve" on the CIS metering head, but the problem here is that it 
seems to be intermittent. Sometimes it buzzes, sometimes it doesn't. When it 
buzzes when the ignition is switch to the "ON" position, then the engine 
fires up on ignition. When it doesn't buzz, then it won't start.

Should this valve be running before startup? Why is it intermittent?

It's been ages since I last heard the fuel pump on my 200, but I can't 
recall if the fuel pump should come on just before startup (ignition to "ON" 
position) or whether it waits for the ignition to be angaged. Which is the 
case?

Thanks for any advice on this problem.

G.