Crank and cam sensor types-hall or inductive?

[disco stu]

I'm looking into timing advance processors for lpg on the pajero, and the different versions depend on what type of crank and cam sensors the engine runs.

Can anyone tell me if the NL pajero uses inductive sensors or hall effect?

My other option was using 2 spark maps in the ecu, but requires adding in extra input to the ecu, adding extra map, and then telling the ecu when to select different maps. This is well above my skill level and I feel will take a lot of learning to get me close to being able to do it. Just adding in a processor seems easier, in the short term at least

Appreciate any help

[TomW]

Pretty sure the NL uses separate inductive crank and cam angle sensors, the older Pajeros Gen 1 / some Gen 2s with distributors have a single hall effect sensor for both crank and cam position contained within the distributor.

[erad]

I can confirm that the NL SOHC engine uses 2 sensors - cam angle and crank angle. I was told that they are Hall Effect transducers, but I cannot vouch for that detail.

[disco stu]

Thanks for the replies guys. Both sensors run 3 wires, but I gather some inductive sensors use 3 wires instead of 2, so it doesn't rule out inductive. I can't find anything in the manuals to narrow it down. I'm not even sure of the principle of the 3 wire inductive sensor to just check power supply to it. It appears to be a question that isn't asked very often at all, but unfortunately the ignition advance modules come are specific to each sensor type

[TomW]

The difference between the 2 and 3 wire sensors (or at least the way I understand it) is that the 2 wire sensor can be thought of as an AC generator, as the engine rotates and the trigger wheel passes the sensor a small AC voltage is generated which is read by the ECU.

The 3 wire sensor on the other hand is fed a constant voltage by the ECU (i.e. 5V) and as the trigger wheel passes the sensor the magnetic field is used to switch a transistor which feeds the supply voltage back to the ECU via the signal lead. This sensor type is sometimes called a square wave sensor as it produces a nice square wave.

[disco stu]

Cheers Tom. Yes, that 2 wire produces the voltage-the inductive version. The confusing part is that I've read that there are 3 wire versions of inductive sensors, so you can only be sure of what type if its a 2 wire version, if 3 wire it could be either. Just trying to work out what the 3rd wire is for on a 3 wire inductive so that might help me narrow it down

I've actually emailed AEB to see if they have a model of timing advance processor they recomend for the pajero. That will tell me what I need to know

[disco stu]

Just to revisit this. Got fairly high consumption at times on LPG, so I'm looking once again at increasing the timing while on LPG. Just to ask again-anyone able to confirm that the crank sensor is digital/Hall effect sensor?