Just had my 1999 AGU chipped at Star performance. AMD code I think, 193 bhp & 211ftlb, goes quite well, Just a question. sometimes when starting only from cold, sounds like a pump is running, don't recollect hearing it before. Doesn't seem to be directly temp related, but only seems to do it in the morning, anyone any experience of this. A/C always off when starting.

Regards

Adoks

The infamous 1.8T cold start rattle perhaps?

Completely normal

Is it a turbine-like noise after start-up which then disappears when the engine is warm? If so it will be the Secondary air pump operating. This pumps fresh air into the engine on a cold start to keep emissions down and once the engine is at normal temp it will stop. The pump is mounted in front of the engine just slightly right of centre and looks a little like a siren.

Sounds likely, goes away quickly during warm up, I do not recollect this prior to chip, so maybe fueling is now different requiring this emmision control system to operate.

Thanks

Adoks

Ah yes, the tractor sound... See your other thread.

1.8T engine noises now have their own Skoda Technical FAQ entry here.