MC2 running very lean

[Dag Bøsterud]

Early this summer my 1990 Audi 100 TQ Sports started to misfire when I first
started it in the morning. I had to rev it at about 2500-3000 rpm for like
10 seconds before it fired on all cylinders. At the same time it started to
misfire occasionally when the turbo was boosting.

The latter problem got worse to a point where the car is now undriveable. It
even misfires before the turbo kicks in.

The spark plugs were checked, and the car runs very lean; they're white as
snow. I've also checked all kinds of hoses, 

I can't find any leaks anywhere. I've checked voltage at the fuel pump,
that's 13,64V. No errors on the fault memory.

It boosts 0,85 bar of turboboost.

 

All sensors, hoses, injectors, gaskets/seals, ignition parts are new, new
spark plugs (Bosch WR6DP),

new Bosch 040 fuel pump.

 

Before the engine started to misfire I hadn't touched anything. What could
be wrong? :/

 

/Dag Bøsterud

1990 Audi 100 Turbo Quattro Sport Exklusiv

153 000 miles