There seems to be lots of conflicting information surrounding this little sucker. So I thought I'd start this thread not only to get mine sussed but for others to have a nice clear explanation. Useful when converting to manual from auto.
My current understanding and please correct me if I'm wrong, this is a discussion not a how to.
On manual cars and autos, but for now let's out lie manuals there are two switches on the gear box. The reverse light switch and neutral position switch.
The neutral switch makes and breaks the circuit from the ecu effecting base idle timing. When the engine is up to tempreture the following timing should be observed;
In gear 25BTDC
In neutral 15BTDC
The idea is that the idle should sit lower whilst the car is at rest, when you engage gear to move away the timing will advance 10 degrees and the idle should jump up a tick. In neutral the circuit is complete and timing decreases, in gear its complete and timing advances. This has two effects should you not connect it or it has failed in the off position. Warm idle sits at 25BTDC, which confuses people who wind it back loosing out on power through the range. With base idle set at 750rpm the car bogs a touch on pull away. I've ended with my idle at 900rpm to reduce this effect.
So on the ecu is pin 44 a yellow wire with a blue stripe. This is the AT/MT neutral switch connection. Grounding this wire to the chassis will activate the neutral switch and reduce to the 15BTDC state. Obviously we only want this when we're in neutral, so this connection is connected to the neutral position switch, the output of the switch goes to ground. This makes and breaks our circuit as desired.
The switch itself is about £60 when buying an OEM Nissan item for the z32. Fortunately it's the same switch used in many Nissan boxes including the Navara D22. Pattern parts are available for these common cars for less than £20. Winner. The same trick also works with the reverse light switch. When converting its sensible to change both or at least check them. They have a habit of failing.
There seems to be lots of conflicting information surrounding this little sucker. So I thought I'd start this thread not only to get mine sussed but for others to have a nice clear explanation. Useful when converting to manual from auto.
My current understanding and please correct me if I'm wrong, this is a discussion not a how to.
On manual cars and autos, but for now let's out lie manuals there are two switches on the gear box. The reverse light switch and neutral position switch.
The neutral switch makes and breaks the circuit from the ecu effecting base idle timing. When the engine is up to tempreture the following timing should be observed;
In gear 25BTDC
In neutral 15BTDC
The idea is that the idle should sit lower whilst the car is at rest, when you engage gear to move away the timing will advance 10 degrees and the idle should jump up a tick. In neutral the circuit is complete and timing decreases, in gear its complete and timing advances. This has two effects should you not connect it or it has failed in the off position. Warm idle sits at 25BTDC, which confuses people who wind it back loosing out on power through the range. With base idle set at 750rpm the car bogs a touch on pull away. I've ended with my idle at 900rpm to reduce this effect.
So on the ecu is pin 44 a yellow wire with a blue stripe. This is the AT/MT neutral switch connection. Grounding this wire to the chassis will activate the neutral switch and reduce to the 15BTDC state. Obviously we only want this when we're in neutral, so this connection is connected to the neutral position switch, the output of the switch goes to ground. This makes and breaks our circuit as desired.
The switch itself is about £60 when buying an OEM Nissan item for the z32. Fortunately it's the same switch used in many Nissan boxes including the Navara D22. Pattern parts are available for these common cars for less than £20. Winner. The same trick also works with the reverse light switch. When converting its sensible to change both or at least check them. They have a habit of failing.