Glow Plug light

[S2 Legend]

Hi folks my A4 audi 2.0tdi is showing the glow plug on the dash plugged it into the computer and its coming up with air filter bypass valve that's the problem? It has been having lagging moments which were increasing and this glow plug symbol shows up.It still taking the throttle and runs normal from cold to hot, I've noticed the stop start was not working sometimes and the fan which usually comes on even short runs isn't coming on not that I can hear anyway but never seen it going too hot. I don't have the error code at hand but had it plugged into another computer a more detailed one but it come up with the same diagnosis but a different error code?

 

[Marky007]

Maybe dpf related just a guess though

 

[S2 Legend]

Hi well I took it to the guy i bought it off and he plugged it into another computer come up with the same code as the small computer gave, turns out it is the air filter bypass valve, the engine light come on today too .... so new valve ordered so fingers crossed that cures it. Mind you it's real confusing when you type into a search engine looking for images of the bit? good god there's no much showed the right part and I would never have picked out the right part unless the mechanic pointed it out. I will advise if my wee audi is cured after next week....