I think he has 2 different problems. Defective ALDA system can cause low power, but something else is to blame for the idle. I think its a clogged fuel screen/filter at least.

__________________
1981 300D 147k
1998 VW Jetta Tdi 320k
2001 Dodge Ram 2500 141k
1979 300D 234k (sold)
1984 300D "Astor" 262k(sold)
Mercedes How-To and Repair Pictorials
I love the smell of diesel smoke in my hair