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Discussion Starter · #1 · (Edited)
I'm gonna try and get this '93 smogged. I'm not sure that'll fly in California because the turbo distributor that's installed has a vacuum module, and one with an unused nipple on the top. I'm pretty sure it'll get flagged as a nonstock part and I'll fail.

Been looking around at replacement CPS sensors.... it's not a fun job, but it's hardly the worst job ever. Obviously the Saab part is NLA, but the broken part is just a Hall-Effect sensor, and there are options.

Edit: So this part is all wrong.... the HKZ101 and its derivatives are replacement Hall-Effect sensors for the distributor....

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The sensor itself is just a standard electronic part, and it seems like several variations are:

HME301
HKZ101
HKZ101S
HKZ101N
HKZ121

They all seem to follow the same specs, which is basically 4-24vDC operating and -40 to 135 C operating. The HKZ part numbers are OE Siemens, and maybe NLA. The HME part number (and its variants, like CYHME301) are copies.

These sensors are generally available from a variety of sources these days, some of which are marketed specifically towards automotive uses, as most European cars used this sensor in the '80s. Still looking there.

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The correct part number for the crank-mounted sensor is either 4AVxxF where XX is 15 through 19. These are Honeywell sensors, there don't seem to be any 3rd party suppliers of these sensors (yet). The difference between 15-19 etc. is the length of the lead - they are electrically the same. It appears everything except the 4AV19F is now discontinued.

The sensors all seem spec'd with the same RED / BLACK / GREEN wires which are VCC+ / GND / SIGNAL. For the Saab Hall-Effect sensor in the distributor, these correspond to GREEN / BLACK / BROWN. For the factory CPS, that's RED / BLACK / GREEN W/ RED STRIPE.

One nice thing I found during this process is a spec for the signal output from these sensors - a 1kohm to 10kohm resistor can be used across the VCC+ and SIGNAL wires for pullup voltage.... I'm sure someone who knows electronics could have told me that, but nobody did. Now I know what I need to test a sensor directly rather than by hooking it up to an ICM to provide that pullup voltage. Happy about that. :)

This is what I've learned... curious if anyone know different!
 

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I'm gonna try and get this '93 smogged. I'm not sure that'll fly in California because the turbo distributor that's installed has a vacuum module, and one with an unused nipple on the top. I'm pretty sure it'll get flagged as a nonstock part and I'll fail.

Been looking around at replacement CPS sensors.... it's not a fun job, but it's hardly the worst job ever. Obviously the Saab part is NLA, but the broken part is just a Hall-Effect sensor, and there are options.

Saabbits in the UK and Modern Classic Saab both sell a "kit" which seems like it's just the sensor and some zip ties, $120-ish either way.

But the sensor itself is just a standard electronic part, and it seems like several variations are:

HME301
HKZ101
HKZ101S
HKZ101N
HKZ121

They all seem to follow the same specs, which is basically 4-24vDC operating and -40 to 135 C operating. The HKZ part numbers are OE Siemens, and maybe NLA. The HME part number (and its variants, like CYHME301) are copies.

These sensors are generally available from a variety of sources these days, some of which are marketed specifically towards automotive uses, as most European cars used this sensor in the '80s. Still looking there.

The sensors all seem spec'd with the same RED / BLACK / GREEN wires which are VCC+ / GND / SIGNAL. For the Saab Hall-Effect sensor in the distributor, these correspond to GREEN / BLACK / BROWN. For the factory CPS, that's RED / BLACK / GREEN W/ RED STRIPE.

One nice thing I found during this process is a spec for the signal output from these sensors - a 1kohm to 10kohm resistor can be used across the VCC+ and SIGNAL wires for pullup voltage.... I'm sure someone who knows electronics could have told me that, but nobody did. Now I know what I need to test a sensor directly rather than by hooking it up to an ICM to provide that pullup voltage. Happy about that. :)

Anywho, point is that buying any of these sensors from any of the myriad of suppliers (including a seller called "SaabRanch" on Amazon) makes it a $20 affair. So, um, I'm gonna get going on that.

This is what I've learned... curious if anyone know different!
If you disable the advance and connect a vac line that is for show , would they know ?
I cant comment on the alternate part numbers, not tried. It will be the pysical dimensions and the ability to mount in the housing that may create issues.
 

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Discussion Starter · #4 ·
If you disable the advance and connect a vac line that is for show , would they know ?
I cant comment on the alternate part numbers, not tried. It will be the pysical dimensions and the ability to mount in the housing that may create issues.
Just it being there would be a problem as it isn't shown on the vacuum diagram.

Remove the vacuum module.
I am considering that, but I am a little concerned about anything unexpected rendering my only spare distributor useless. And, then I have a hole in the side of the can that I'd need to fabricate a cover for. I can spare $20 and a couple hours... And it'll be a fun experiment! :)
 

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Discussion Starter · #5 ·
Looks like I made an error in my original post, which I have since corrected.

TL;DR:

HKZ101 = distributor
4AV19F = crank sensor

The former is $20-$40, the latter between $50 and $90 depending on the source.
 

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Looks like I made an error in my original post, which I have since corrected.

TL;DR:

HKZ101 = distributor
4AV19F = crank sensor

The former is $20-$40, the latter between $50 and $90 depending on the source.
I had wondered re the pricing you had listed. Last time I purchased a Cps I paid at least $50 ( many years back) and the last time I looked I was seeing around the $90 for the 4AV19F, I have not tried a 4av19f so unsure if physical dimensions work for its housing ,
 

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Discussion Starter · #7 ·
"4AV" is the series, the next two digits are the lead length, and the final is the revision. As long as it's 4AVxxF it's exactly the same package & electronics. But, as this is an old sensor it appears everything except the "19" version is NLA.... so, you get what you get. :)
 

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"4AV" is the series, the next two digits are the lead length, and the final is the revision. As long as it's 4AVxxF it's exactly the same package & electronics. But, as this is an old sensor it appears everything except the "19" version is NLA.... so, you get what you get. :)
Sounds like a winner , albeit more expensive than what you had in mind. Avoids risking/compromising your singular spare dizzy. Thanks for the clarity re tail length , I missed that in your earlier post/correction.
 

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Discussion Starter · #10 ·
I reached out to Honeywell yesterday and heard back this morning.... the 4AV19F is also now discontinued. There is a fair amount of unsold inventory, but this sensor will probably disappear off the face of the earth within a year or two. Maybe it'll be like the HKZ101 and a Chinese manufacturer will pick up where Honeywell leaves off... but who knows?
 

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I feel like i'm totally in the dark here. Can some explain the whole CPS thing? When I re-sealed my oil pump few months back i expected to find a CPS but it was not there. I remember Jim or someone saying simply "Then your car doesn't have one". So, i shrugged it off. Then the recent post with the Harmonic balancer coming apart and the poster talking about his being removed with some sort of option, has me wondering.
Is mine missing because at some point it was replaced with a distributor option?
 

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Discussion Starter · #12 ·
Distributor is sensor is on '85-'93 c900T 16v and '86-'87 16v cars. Crank sensor is on '88+ c900 16v cars. I can only imagine turbos kept the distributor because Saab needed the vacuum retard module for boost, and that there wasn't an electronic solution available to them... something Bosch hadn't invented yet, or the cost of implementing was too high, etc. The crank sensor is such a PITA when it brakes, but it's really a better solution. Unless of course you're trying to mess with your timing, and it sucks. :)
 

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I feel like i'm totally in the dark here. Can some explain the whole CPS thing? When I re-sealed my oil pump few months back i expected to find a CPS but it was not there. I remember Jim or someone saying simply "Then your car doesn't have one". So, i shrugged it off. Then the recent post with the Harmonic balancer coming apart and the poster talking about his being removed with some sort of option, has me wondering.
Is mine missing because at some point it was replaced with a distributor option?
If your car is turbo... the sensor is within the distributor (called Hall effect sensor), always was. The recent post about that balancer is talking about an NA car that for that MY had a crank mounted sensor (CPS) , but at some stage the CPS failed . As a workaround ( to avoid removing the balancer) a Distributor had been fitted with a dizzy mounted sensor (hall effect) .

Years ON Now that the pully is off the owner is talking about reverting to the original mointing point of a CPS that he has in his spares .
He will leave the Distributor where it is but disconnect the wiring from the hall effect sensor , He will connect back into the pig tails he has from his re fitted CPS sensor .
In this scenario the distributor will act purely as a Spark distributor , it is not collecting a signal from a sensor , that signal will be coming from the CPS , not the dizzy . Hope that helps ...
 

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If your car is turbo... the sensor is within the distributor (called Hall effect sensor), always was. The recent post about that balancer is talking about an NA car that for that MY had a crank mounted sensor (CPS) , but at some stage the CPS failed . As a workaround ( to avoid removing the balancer) a Distributor had been fitted with a dizzy mounted sensor (hall effect) .

Years ON Now that the pully is off the owner is talking about reverting to the original mointing point of a CPS that he has in his spares .
He will leave the Distributor where it is but disconnect the wiring from the hall effect sensor , He will connect back into the pig tails he has from his re fitted CPS sensor .
In this scenario the distributor will act purely as a Spark distributor , it is not collecting a signal from a sensor , that signal will be coming from the CPS , not the dizzy . Hope that helps ...
okay, i get it. No one explained that before. I have a turbo so mine was always in the disti
Make perfect sense now. Thanks
 
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