Mk4 1.8t N249 Valve Question - Next To No Boost??

[Ashmond]

Got a n249 fault mechanical malfunction tried replacing with two other n249 valves that have come off another aum engine (they work) and im getting the same fault. Also disconnected it comes up with different fault (open circuit on vagcom) so the ecu is connected right to the n249 valve. Also tried bypassing it and using new one way valves in the pipe work to the n249 but no luck. We also took the pipe off the side of the n249 and can see the valve working as it should.

Everytime we run a test on vagcom it comes up with N249 mechanical malfunction. Getting a tiny bit of boost but nothing compared to how it should be delivering. Will be replacing the maf this weekend to see if thats affecting the boost but just wondering if anybody had any suggestions..

Ta

Ash

[ben44]

had a similar problem on a mk4 1.8t before, check the wastegate/actuator isnt stuck open.indication of this problem is a noisier exhaust note.

[topher]

mechanical malfunction detected by the n249 is usually a problem at the DV. check all the hoses to it, especially the naff little vac hose on the top that has a tendency to crack.

[Ashmond]

had a similar problem on a mk4 1.8t before, check the wastegate/actuator isnt stuck open.indication of this problem is a noisier exhaust note.

Ok will do this, the exhaust is slightly louder but nothin really noticable! Cheers!

mechanical malfunction detected by the n249 is usually a problem at the DV. check all the hoses to it, especially the naff little vac hose on the top that has a tendency to crack.

Well we have bypassed the n249 and all the pipes to the dv are sweet, we checked them the other day 

[Ashmond]

Checked the wastegate and the actual gate was very strong and kept popping back tightly so we knew it wasnt that.

I plugged the MAP sensor and plugged it back in whilst the engine was running (read it on a vw website) and after restarting it my car started to boost again.

Problem fixed - cheers for your help anyway lads!