starting problems

[jonnyj80]

my audi 80 2.3 5 cyl starts fine then after 5 seconds almost cuts out as if it is being starvted of fuel. runs rough for 20 seconds or so then it runs normal again.

anyone had problems like this?

[scotty33]

Is this cold starts, or hot starts? Does it restart and run well after you get it through the rough patch?
There is a chance the injectors or the cold start valve (the extra injector in the intake) is leaking. This leads to fuel being dumped into the ports (some of this may end up in your oil!), which means the fuel system has then lost its pressure. The car will fire up on the residual fuel, but the system takes a short while to repressurise. The proper cure would be new injectors/csv.
The system includes a fuel accumulator, which is supposed to store a quantity of fuel at pressure. When the injectors are worn/leaking, bypassing the accumulator could be the way to go, less fuel will leak away, and the system will repressurise quicker (in my opinion).
You could pull the cold start valve and the injectors and stand them in glass jars overnight,this will show you how much they are leaking? If none, then it is likely the check valve on the fuel pump is leaking, allowing the pressure to escape back through the fuel pump into the tank.
If you pull the injectors, you will need new O ring seals for them.

[jonnyj80]

it happens from cold start then runs fine after.
im thinking of doing a top end decoke so i'll have a look then.

cheers for the info much appreciated