Re: Fuel Distributor '82 2.2i

[paul.heneghan@bbc.co.uk (Paul Heneghan)]

Date: Fri, 11 Apr 1997 16:58:20 +0100

>Yesterday, my A100 broke down.  Doing 80Mph in the fast lane too.  Seems
>like the fuel distributor got stuck open, so when I changed into 5/E the
>engine power cut.

That's bad luck.  I've always considered the FI system to be extremely 
reliable and long lasting on VW/Audis.

>I phoned the dealer for a price for a new one, I was quoted 613 ukp plus
>VAT@17.5%.  I asked if that included the rest of the car!

Dealer costs are incredible.

>Despite my reluctance to buy second hand parts, after a set of injectors
>lasted about two weeks, I got hold of a complete airbox/flow-meter/fuel
>distributor unit and fitted it.  The engine now runs, but I only seem to 
get
>reasonable power between 3000 and 5000 rpm.  The old unit only gave good
>power between 1500 to 3500 rpm.  Is this just adjustment, or should I just
>carry on driving at higher revs?

You need to centralise the plate, check its rest position (as detailed in 
Haynes, Bentley etc.), check for free movement (with care, it is possible to 
take out and clean the little fuel dist. piston) and set the CO adjusting 
screw.

>I noticed that the Airflow plate had alot of carbon build up around the
>mouth, so I cleaned this with a solvent, and the plate will now move freely
>into the gap.  I also notices light resistance when pulling the plate up, 
as
>if it was flowing through oil.  It also takes a while to settle.

>From what I remember, it should have a slight resistance when being pulled 
upwards, but should return down fairly quickly ( I seem to remember mine 
bouncing off the endstop slightly).

>I take it
>that this is the fuel distributor plunger taking time to return to its new
>position.  Basically, is this normal, or is this distributor almost
>knackered too?  I remember Phil previously mentioning that the plate should
>move freely.

>It also gives me great cold start problems, engine will pop or cut out 
under
>acceleration, until it is left a good while idling.  It takes about 5miles
>further driving before resonable acceleration is regained.

Check the cold start injector.  When the engine is cold, it should spray for 
a few seconds and then stop (without leaking).  If it doesn't spray at all, 
then you may have a thermotimeswitch problem (this decides how long to spray 
for based on ambient/engine temperature).

Also, if it takes a long time to warm up, consider replacing the pressure 
regulator.  This is bolted to the engine (same side as sparkplugs, but below 
them in the middle) and adjusts FI pressure accorcing to engine temperature 
(and sometimes load).  It is a box with a couple of FI connections, and 
electrical connection and might have a vacuum connection as well.

>I was planning to fit a second hand cold start valve today, and then get it
>tested and krypton tuned.  Any ideas?

What about bringing it to a Bosch FI specialist?  I know Phil has a poor 
opinion of them, but they're better than nothing (and almost certainly 
better than an Audi dealer).

Paul
paul.heneghan@bbc.co.uk
1984 Audi 80 quattro
1989 Audi 100 Avant