Crank Position Sensor testing LH2.4

[Stereophile33]

Cannot find what the heck Bentley calls it so I can test it. I want to find the connector and test.

This is for PNP MSI

Let me know,
Jonathan

[thelostartof]

look @ the back of the bellhousing ... behind the head on the top of the block .. and follow its wire up .. should be a 3 pin connector on the firewall more so to the center but more so on the drivers side

[Stereophile33]

any idea which pins to test?

Should it pulse?

I get a constant 9.44 Volts

[JW240]

any idea which pins to test?

Should it pulse?

I get a constant 9.44 Volts

the sensor itself should have a certain resistance. the older types around 160 ohm (pin 1 and 2 iirc) and the newer types 230 ohm afaik. it has been a few years ago since i replaced it....

[945ti]

http://brickboard.com/FAQ/700-900/EngineSensors.htm#Crank_Postition_Sensor

[Stereophile33]

http://brickboard.com/FAQ/700-900/EngineSensors.htm#Crank_Postition_Sensor

brickboarder.....:grrr:


:)

Thanks James,

SO I have 180 ohms tested, but only .3V while cranking. I have been told that 2 V is more like what i need.
Jonathan

[740Weapon]

brickboarder.....:grrr:


:)

Thanks James,

SO I have 180 ohms tested, but only .3V while cranking. I have been told that 2 V is more like what i need.
Jonathan

nope. mine gimme about 0.3V while cranking too. so did the replacement i baught because i thought 0.3V rms was too low.

0.3V should get MS to start. you should prob mickey mouse into the MS harness to see what the voltage is while idling, if you can get there. or go to cragslist and get a cheap used oscilloscope so you can look at the signal itself.

[jutny]

VR sensors are teh ghey...

they dont generally break though.

[linuxman51]

nope. mine gimme about 0.3V while cranking too. so did the replacement i baught because i thought 0.3V rms was too low.

0.3V should get MS to start. you should prob mickey mouse into the MS harness to see what the voltage is while idling, if you can get there. or go to cragslist and get a cheap used oscilloscope so you can look at the signal itself.

could be why you had issues, usually on the ones I play with (including my own), ms won't pick up a signal much lower than about 1.2v
You can play with the two pots on the board (counter clockwise) to drop their filtering ability.

Also depending on which two wires you grab to test you can get odd results.

It is worth mentioning that EZK is a little better at picking up a weak sensor, and also airgap on the sensor itself can affect how well it operates.

[740Weapon]

could be why you had issues, usually on the ones I play with (including my own), ms won't pick up a signal much lower than about 1.2v
You can play with the two pots on the board (counter clockwise) to drop their filtering ability.

Also depending on which two wires you grab to test you can get odd results.

It is worth mentioning that EZK is a little better at picking up a weak sensor, and also airgap on the sensor itself can affect how well it operates.

maybe i have the "slow" starter and you have the "fast" starter?

cuz its VR, the voltage should go up when the motor spins faster or gets to idle speed. so its not like the MS will always see 0.3V.

the bracket on the bellhousing isnt adjustable or anything to get the sensor closer afaik, so seems mostly like a lose-lose situation if the VR sensor wont behave.

maybe grinding the VR sensor mount hole itself could get the thing a hair closer and get the voltage up.

maybe the thing does get a funny bias if it isnt close enough.

[jutny]

i wonder if one could use the stock ezk to trigger the MS... let it do its black magic to the VR signal, and then hijack the output for the ms?

is that totally half-baked or might there be some kind of breakthough there, i still have my ezk in the car.... i'd be willing to test, time to try finding the pinouts for the ezk... what kind of output does the ezk give?

Ken, in the other thread (3500rpm misfire thread) said his signal got cleaner when he moved the VR away from the toothed wheel... allthough he's using a 36-1 on the crank pulley with a bracket, and we're using the stock lh2.4 60-2 stuff...

ARGH!

[Stereophile33]

no dice....I got nothing. Any other ideas?

[benflynn]

nm

[AnthonyH]

Humm, on my MS, I have the sensor on the crank, to get MS to pick the darn thing up, the sensor virtually 'rubs' on the crank wheel. This is with the 2 pots turned down to the least filtering. You may want to remove the sensor, file the mounting area down so you can decrease the air-gap. This will increase the voltage.
btw. this is a Toyota VR-sensor and a 60-2 bmw wheel.

[Stereophile33]

new sensor, .4v

Got nothing. I guess I can work at shaving down the sensor bracket. Seems like a long way to go. .4V to 2V.
Jonathan

[blkaplan]

why not use an op amp and amplify the signal to the desired 2V?


all you need is a op amp and 2 resistors... .4V * R1/R2= 2V

[Stereophile33]

good idea....I just ground the bracket down 10 thou. reads .59 volts now......grrrrrr and I blew a coil. Apparently LH2.4 pnp does not have dwell control....coils smell nasty.
Jonathan

[Karl Buchka]

why not use an op amp and amplify the signal to the desired 2V?


all you need is a op amp and 2 resistors... .4V * R1/R2= 2V

It's actually

V_in*(1+ R2/R1) = V_out

assuming R2 is in the feedback circuit, R1 is on the negative terminal, and V_in on the positive terminal.

[poulson01]

new sensor, .4v

Got nothing. I guess I can work at shaving down the sensor bracket. Seems like a long way to go. .4V to 2V.
Jonathan

You could just set cranking ign to time based?

[945ti]

good idea....I just ground the bracket down 10 thou. reads .59 volts now......grrrrrr and I blew a coil. Apparently LH2.4 pnp does not have dwell control....coils smell nasty.
Jonathan

The 124 ign module does not have dwell control. You can use the bosch saab 139 prevents further coil charging should you leave the car sitting with the key in for prolonged periods of time. That or use COPs with coils with integrated ignition modules that shut them off as needed.