2004年8月12日 · I ran my recently purchased RossTech diagnostic tester on my 2001 TT and got one error: 17608 Boost Pressure Control Valve (N249) mechanical malfunction. N249 turns out to be the recirculation control valve for the turbo. I located it but according to the workshop manual from Bentleys Publishers I need special tools for testing.

2020年11月15日 · In Layman’s terms, the N249 is a valve solenoid that is connected to the intake vacuum source to the back of the diverter valve (DV) and it controls the boost signal to the DV telling it when to open. Essentially it is a part that is there …

2004年5月14日 · It seems, the N249 is just a simple two way solenoid valve that can connect the BPVs directly to either the manifold (vacuum/pressure), or to the vacuum reservoir (hard vacuum) with no in-between. I haven't had mine out, so I don't …

2017年2月5日 · In the manual N249 is called 'Turbocharger air recirculation valve' When you lift off the throttle it opens to relieve the air pressure in the inlet tract. That excess air is returned to the air inlet side of the turbo thus keeping the turbo spinning and giving a faster response when you reapply throttle.

2012年5月14日 · Audi service centre has told me that there is a 'stored fault' when they hooked it up to their diagnostic machine. The fault is with the air recirculation valve n249, the technician said it's probably torn and needs replacing. The part costs £15, …

2008年2月21日 · The N249 switches vacuum from the vac reservoir to open the DV when there is little or no vacuum in the intake manifold. Obviously, disconnection defeats the functions it provides, and effects the fuel economy and emissions variously.

2015年6月30日 · But like I said... the N249 is one of the ECU's protection systems for the engine... it allows the ECU to dump boost if it detects a problem... the fact you had the code at all suggests the ECU was trying to dump boost... the fault code is normally the result of the boost not dropping quickly enough so the ECU assumes the N249 is not operating ...

2011年10月24日 · Is there a guide to do the n249 bypass on the aum engine? I've found loads of guides for other engines but there always a comment about it being a bit different on the aum. Also I've read about using some sort of resister so that everything can be removed after the bypass. A3 1.8t Quattro Sport!

2020年4月19日 · Junking the PCV and the n249 really simplifies the vacuum and breather. The N249 valve will open the DV when cruising when the ECU asks for reduced boost for better fuel efficiancy, it will also open the DV valve quicker on gear changes or throttle lifts. I looked at the delete but thought it was beneficial to keep it.

2010年5月15日 · Had a bunch of codes, including N249, boost pressure not reached, and cylinder misfires. Replaced the DV which didn't seem to help and the Wastegate Actuator which fixed the noise and boost leak, but still getting this one fault code.