Wilky

Thanks Peter good to get a response so efficiently too.

Still not sure what is making the occasional steam exit trough bonnet vent. Only done it 3 times in 3 months noticed when in trafic. 

Will keep looking thanks Wilky

Hello ...i am new to jaguar and now have an s type with the same problem as above so will try these tricks thanks. Mine occasionally also suddenly steams up through the windscreen demist system when engine is fully warm.....and at the same time steams through the outside bonnet vents near windscreen.....only noticed this when in trafic.

No sign of engine overheating whatsoever. So assume this also must be something to do with the AC system. Any ideas on that one ? rather weird and disconcerting although strange that it happens occasionally. thanks. Marcus