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Discussion Starter · #1 · (Edited)

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Steve, Just curious as to what kind of information the cam angle sensors provides to the ECU that could not be provided from the crank sensor?
 

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Discussion Starter · #3 · (Edited)
Steve, Just curious as to what kind of information the cam angle sensors provides to the ECU that could not be provided from the crank sensor?
The knock sensors and cam angle sensor work together see 94 electrical wiring manual pag 562 for info.
 

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Steve, Thanks for all that information. However, my questions remains. If the cam angle sensor is a timing sensor for the knock sensor, why couldn't the crank sensor, which also serves as a timing sensor for the ignition, provide the same input to the ECU.

With the newly acquired 24v LS, I have a lot to learn about this M1.7 system. Just yesterday, I found that the Idle Air Regulator (IAR) has three pins instead of the 2 pins on the 91-93 M1.4. Mine makes a humming noise with the key in the on position and engine not running, and I wonder if that is normal. Why does it have the extra pin anyway? It took me a while to trace the noise because I was not expecting it from how the earlier IARs behave.
I also noticed that the throttle position sensor is different when it wasn't making the familiar clicking sound. I figured that one out already as having a contineously variable resistance output instead of a double switch.
Thanks, Alfahill
 

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The crank sensor and the cam angle sensor are the same; the difference is in the length of the pigtail.

Having just had these items off, I know they work on the Hall effect, but how does the knock sensor work? Is it piezoelectric?
 

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Alfa hill IAC

Yep mine hums too with key in run position. It kind of drones, I would say, it doesnt seem to be able to carry a tune very well.:)
 

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It just doesn't know the words.
 

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Take care. I had a cambelt slip because a malfunction in IAR. It did´t keep down the revs at startup. Instead of 1200 revs at startup i got 3000 revs and with almost no oilpressure (dry cams) in that moment the cambelt slipped.

JK
164 Q4
 

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Steve,

I don't know if this works right away, but here you can find sensorpartnumbers.

The numbers look kind of short for a Boschnumber, but maybe it helps.

Its for a Q4 btw.....

PartsBase
 

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Nope, it doesn't work right away.
Type JL-HG-95 (my licenceplate) in the yellow rectangle(dutch licenceplate)

Select motormanagement and ODB
Select "impulsgever"
Selcct any of the sensors for info....
 

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FWIW, the Bosch KS pictured above looks very much like the one used on the Saab 900/9000 Turbo, except there's no pigtail on the one spec'd for the Saab - the quick-connector is built right into the sensor. I was initially going to suggest that they're swap-able, but I imagine the harness on the Alfa won't reach a pig-tall-less KS, and you really don't want to go splicing into a sensitive circuit like this to extend it.
 

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Discussion Starter · #13 ·
Well, looks like maybe 0 261 231 095 is Bosch number for 60810791 knock sensor
 

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hi
is there any resion not to buy this cheep knocking sensor for my 1994 v6 24v ?
96253615 Knock Sensor for Daewoo Lanos Fiat Coupe Lancia Kappa Alfa Romeo 145 | eBay


at the end i ordered fae 60111, its from spain
other company is "facet"

here are all your options :
aLFA: 60592752, BOSCH: 0261 231 095, 0261231095, FIAT: 60810791, QUINT: XKS31, DAEWOO: 96 253 615, 96253615, FACET: 9.3023, ERA: 550230, FAE: 60111, MEATDORIA: 87357, STANDARD: 19527
 

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The knock sensors and cam angle sensor work together see 94 electrical wiring manual pag 562 for info.

Hello Steve, I am Paolo,
Thanks for this old post. I have read carefully the picture about the RPM inductive sensor.

Correct me if I am wrong:
the higher the RPM, the higher the output signal in Volts, then :interpreted" by the ECU in RPM
But, the output of the sensor is a signal in Volts, proportional to the effective RPM of the engine


Therefore this signal cannot be used "as it is", to detect the RPM of the engine (as the signal of the old coils in the 80's GTV 2.0 or GTV6, to make an example, where 1 electric click meant 1 RPM, 1000 clicks meant 1000 RPM, and so on)

Thanks in advance

Paolo
 

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Crank sensor on 24V is a garden-variety hall effect sensor that outputs a pulse train that is proportional to the crankshaft speed. The pulse train frequency increases as the crank pulley speed increases. Each tooth of the crank pulley wheel outputs a single pulse in the time domain. It looks on the oscilloscope like a square wave as I recall as we know that HE devices have low hysteresis.
There is a spot on the crank toothed wheel that is 'missing' a tooth. Thats the longer duration active low (as I recall) that is used to determine actual crank speed (one longer duration pulse = 1 complete revolution. Alternatively a counter can be used (once you count the number of teeth on the crank pulley that pass in front of the HE sensor) that would be usable (digitally) to determine actual crank RPM
 

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Thanks a lot for the detailed description!
So if the output is a pulse train frequency (Voltage=12 or 5 volts?), a device capable to read a signal in frequency (of that voltage) should be able to tell me that specific frequency/RPM, am I correct?

Thank you
Paolo
 

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Discussion Starter · #19 · (Edited)
Thank Goats for his explanation. I am away currently from all my Alfa Romeo 24v technical data until at least December and my memory is not what it used to be and that original post was back in 2007.
 
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