Search:

that will be interesting because i had to replace mine around 6-8 months ago so the way i see it those bastards owe me some money!

Like TD said. Clean the MAF. But if its foobar the cleaner will do jack. What mods have you got besides the zorst? Dawes and needle valve? EGR block?
Could be a number of things. A vacuum leak may...

Does that pipe connect to the top of the thermostat housing or expansion tank? If it's the thermostat housing, your thermostat is stuck open or missing completely.

Edit, looking at that pic...