I've just rebuilt my friends 2000 w plate 1.9 TDi. It's the AHU engined 90bhp version. There are vacuum pipes at the bulkhead, and I can't figure out where on of the goes. Can anybody help? I know one of the goes to the egr, and another to the air filer housing, but there is another not attached to anything which I can't figure out. The turbo isn't cutting in, and I hope the 2 are related.