2010年4月14日 · The N75 valve controls the turbo wastegate actuator via directing air pressure to it by actuating a tiny solenoid when the ECU decides its neccesary. this solenoid can turn on and off VERY fast to keep the boost at the proper constant. basically it prevents overboost electronically instead of relying on a set tension spring on your wastegate.

2008年4月15日 · This schematic should help some of you understand how the N75 does it's job. Happy browsing....

What is the N75 Valve? The N75 valve is a fundamental part of controlling boost on a 1.8T engine. Its a small electronic solenoid valve that the ECU regulates to control how much boost the turbo has to create.

The N75 valve, also known as the wastegate frequency control valve, is a solenoid valve that is controlled by the engine’s ECU (Engine Control Unit). It is usually located near the turbocharger and has vacuum lines connected to it.

2004年11月27日 · the n75 controls the vacuum to the turbo VNT actuator. it's a dumb device - a simple valve that is controlled by the ECU (and the "tune") to open/close vanes a certain amount to achieve desired boost. open the vanes fully for least possible boost by passing no vacuum (valve 100% closed) or close the vanes for maximum possible boost by passing 10...

2007年9月20日 · The N75 has three ports: one to the manifold where manifold pressure is sourced. The second goes into the turbo compressor inlet pipe as a "bypass" and the third goes to the wastegate actuator. The job of the N75 is to present a fraction of the manifold pressure to the wastegate actuator.

2002年7月29日 · As we know, we got a turbo on our engine which produces boost. The turbo is "driven" by the exhaust gasses our engine produces. Exhaust spools up the turbine in the turbo which is mounted on the same driveshaft as the compressor which then generates boost.

There is a sudden change in engine performance, and the engine has marked reduction in power. It seems as if the power improves a little with higher rpm: 70mph (120kph is possible, but it takes a long time to accelerate). The engine is smooth, and starts as normal. There is no warning light. In fact, the engine behaves completely normally ...

2006年8月9日 · Changing the N75 valve on the 2.7T engine is very straightforward. In fact, it's so straightforward that this writeup could be considered quite unnecessary! I figured I'd post it (since I had it anyway) in case anyone was ever on the fence about doing it themselves, to reassure them beforehand that it is very do-able.

2010年7月6日 · Use a short section of vacumm hose (8") and connect between the "Vac" port on the N-75 and the vacumm nipple on the main checkvalve. This will eliminate every thing else in the vacumm system. If you get boost your N-75 is operational. If you want to verifi your N-75 you can remove your N-18 (EGR solenoid) and connect it to your turbo.