DIYPNP on a 99
#41
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#43
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MS2extra manual says the signal voltage from the KnockSenseMS is too high for the processor port directly and they suggest using an input circuit with a zener and resistor. Is this not necessary then?
#47
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That circuit is for the GM knock sensor module; the KnockSenseMS is a different device that puts out the voltage the MS needs already.
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#49
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It worked great. I pulled it 2 weeks ago, to mod it for direct coil, sequential fuel, and a couple other things such that it would play nice in parallel with the stock computer.
Have not had time to complete due to house repairs caused by the big floods we had several weeks back.
Have not had time to complete due to house repairs caused by the big floods we had several weeks back.
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I really wonder why the µs inputs work fine and the ms inputs don't.
The opto-circuits are pretty much identical (apart from a schottky diode instead of 2 normal diodes).
Opto µs
opto ms
The ms VR circuit is very similar to the µs circuit and can be easily modified
VR µs
VR ms
I'm tempted to convert the ms opto and VR circuits to those of the µs in my next ms build.
OTOH, I can build Jason's low battery circuit in the opto area and both of Abe's input circuits in the VR area.
Should I convert to the µs circuits, I don't have room for the low battery circuit (proto area is completely full already with other ciruicts).
Bah, choices.
Last edited by WestfieldMX5; 10-14-2009 at 04:24 PM.
#59
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Hey, hadn't seen this thread before! Congrats on getting it working. Looks like there's a lot of wiring, but it makes sense, it IS a general purpose board, and for that it works really well. Yes mine has (so far?) the odds and ends all taken care of (alternator, AC, VICS, etc etc), but admittedly this is less I/O limited, by using the microsquirt it's more approachable and flexible than any MS-II based board would be.
I forget exactly what I did, but the AC switch is something pathetically easy, like a single diode and some wire. It's in the AC thread, at any rate, but you don't want to go wasting MS-I/O unless you're also going to try to use it for anti-stall.
How's the idle??
As I got a better tune, I would have overboost issues. Adding extra timing in helped keep it under control.
Noise on the inputs, or noise on the general lines?
That's REALLY interesting the uS is ok with the inputs that way. It's the same exact processor as the MS-II, or some variation? It doesn't make a lot of sense to me at first glance, unless it's just getting away from the.... 'less adequate' MS3.0pcb
Someone may have answered this, but you should be fine. the KnocksenseMS is called that because its tuned and set up for the MS.
*IF* you tell Boris you have a 99 miata, he'll set it up special to use the OEM sensor. I sent him one long ago (lent me from someone, maybe you or olderguy?), and he developed a tune for it. Then I take the wire from the OEM harness, run it out to the knocksense, then back in and into the CPU
OH GOD NO. Do not run a cas. You might as well run MS-I. You get horrible timing, like, 5 degrees of error.
A 60 tooth is a fine idea, though.
Shoot, there was one more point, but I forgot it. C'est la vie.
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It appears to me that when you push the A/C button on the climate control panel, 1P on the PCM is pulled to ground (through the pressure switch). When 1P goes to ground, the PCM grounds the compressor and a/c fan relay coils through 1S and 1I respectively. What this means is that A/C control will be pretty easy--and can be done without using an input on the MS. Just jump these 3 pins.
How's the idle??
Also have what looks like a little random noise in the datalogs. I ran extra grounding to the DB15, but didn't actually hook it to the car. I think it needs to be done.
That's REALLY interesting the uS is ok with the inputs that way. It's the same exact processor as the MS-II, or some variation? It doesn't make a lot of sense to me at first glance, unless it's just getting away from the.... 'less adequate' MS3.0pcb
MS2extra manual says the signal voltage from the KnockSenseMS is too high for the processor port directly and they suggest using an input circuit with a zener and resistor. Is this not necessary then?
*IF* you tell Boris you have a 99 miata, he'll set it up special to use the OEM sensor. I sent him one long ago (lent me from someone, maybe you or olderguy?), and he developed a tune for it. Then I take the wire from the OEM harness, run it out to the knocksense, then back in and into the CPU
A 60 tooth is a fine idea, though.
Shoot, there was one more point, but I forgot it. C'est la vie.
Subscribed.
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I forget exactly what I did, but the AC switch is something pathetically easy, like a single diode and some wire. It's in the AC thread, at any rate, but you don't want to go wasting MS-I/O unless you're also going to try to use it for anti-stall.
How's the idle??
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As I got a better tune, I would have overboost issues. Adding extra timing in helped keep it under control.
Noise on the inputs, or noise on the general lines?
That's REALLY interesting the uS is ok with the inputs that way. It's the same exact processor as the MS-II, or some variation? It doesn't make a lot of sense to me at first glance, unless it's just getting away from the.... 'less adequate' MS3.0pcb
Someone may have answered this, but you should be fine. the KnocksenseMS is called that because its tuned and set up for the MS.
*IF* you tell Boris you have a 99 miata, he'll set it up special to use the OEM sensor. I sent him one long ago (lent me from someone, maybe you or olderguy?), and he developed a tune for it. Then I take the wire from the OEM harness, run it out to the knocksense, then back in and into the CPU
*IF* you tell Boris you have a 99 miata, he'll set it up special to use the OEM sensor. I sent him one long ago (lent me from someone, maybe you or olderguy?), and he developed a tune for it. Then I take the wire from the OEM harness, run it out to the knocksense, then back in and into the CPU
OH GOD NO. Do not run a cas. You might as well run MS-I. You get horrible timing, like, 5 degrees of error.
A 60 tooth is a fine idea, though.
Answers are a little ambiguous because once I got the car running, it only stayed that way for a few days. I've pulled the DIYPNP out of the car and reconfigured it for parallel operation. I've almost finished the wiring harness. A trip to Frys for some more wire and heatshrink will get it finished. Can't believe I used a 100' spool of wire!!
Sure hope I can get CEL-free parallel operation.
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