the thread where Savington asks a lot of really, really dumb questions.
#101
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Julian, if I opened up the box and snapped a couple photos would you be able to tell me what I need to cut/move?
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Or instead of taking apart the board/moving jumpers/cutting leads/resoldering/whatever, just use move (physically and software wise) injectors 1 & 2 to 5 & 6, after you've done this check to see if it's the problem.
So ... my suggestion is test the injector outputs manually to see if you have 9 and 10 in the connector at all or whether those two are connected to pins for 1 and 2 and you either have to move some jumpers on the daughter board to separate them or you may even have to cut some traces on the daughter circuit board and route them to the proper pins.
To do a test:
1. Open AEMPro, go to Options -> Injector screen
and turn off all injector outputs there (so the software temporary doesn't treat them as injectors).
2. Disconnect the plugs from the injectors.
3. Since all our injector outputs are not treated as injectors anymore but as general LS drivers.
In AEMPro, open Options -> Configure Outputs and there manually toggle Fuel 1, 2, 9 and 10 to ON one by one.
Monitor their status in a parameter window (Ctrl-P) and check with a multimeter the pins 2U, 2V, 3O and 3P.
My prediction is that when Fuel 9 is ON, pin 2U will be grounded instead of 3O and when Fuel 10 is ON, pin 2V will be grounded instead of 3P.
So, to make 9 go to 3O and 10 to 3P, you'll either have to move some jumper or do some trace cutting and/or soldering on the daughter board
This is just for Savington's AEM EMS. Jason uses one with a Honda daughterboard so I guess his is fine.
To do a test:
1. Open AEMPro, go to Options -> Injector screen
and turn off all injector outputs there (so the software temporary doesn't treat them as injectors).
2. Disconnect the plugs from the injectors.
3. Since all our injector outputs are not treated as injectors anymore but as general LS drivers.
In AEMPro, open Options -> Configure Outputs and there manually toggle Fuel 1, 2, 9 and 10 to ON one by one.
Monitor their status in a parameter window (Ctrl-P) and check with a multimeter the pins 2U, 2V, 3O and 3P.
My prediction is that when Fuel 9 is ON, pin 2U will be grounded instead of 3O and when Fuel 10 is ON, pin 2V will be grounded instead of 3P.
So, to make 9 go to 3O and 10 to 3P, you'll either have to move some jumper or do some trace cutting and/or soldering on the daughter board
This is just for Savington's AEM EMS. Jason uses one with a Honda daughterboard so I guess his is fine.
#103
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What Tim suggests also won't break the box warranty if it is brand new.
Move the OEM injector harness wires from inj 1 & 2 to something like 5 & 6. In the software in "Options->Injector" disable 1 & 2 (disable = uncheck "Active") and enable the two new ones (set them as primary, etc. options there just like 1 & 2 were).
Then open the "Fuel->Advanced Fuel->Injector Phasing" and put the values you have from Inject Tooth #1 & #2 into the two new ones you used.
After this start the engine to make sure you did the switch correct.
Then connect the VVT solenoid to injector 2 (or 1 - whichever the 9 is shorted to)
Last edited by j_man; 03-09-2010 at 01:03 PM.
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OK, I moved injectors 1 and 2 over to outputs 7 and 8. Still not totally sure why activating injector 9 as VVT control is grounding out 2/10 but whatever. Hopefully it's solved now. Changed the active injectors and injector phasing and the car fired up fine. I will play around more with VVT tomorrow and see if I can get it to run the circuit without locking an injector open, and then power the solenoid and start zeroing in on some settings.
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It appears to be solved. I can activate PWM9 in the software and the injector stays closed as it should. I'll move on to settings today/tomorrow.
One quick question about knock sensing - I hooked my Bosch sensor up to the AEM and stuck it on the side of the block. I placed the sensor in the OEM location using the FM adapter. I can tap the sensor and get ~1v out of it, but when the car is idling and revving it won't go above .02v. Any ideas?
One quick question about knock sensing - I hooked my Bosch sensor up to the AEM and stuck it on the side of the block. I placed the sensor in the OEM location using the FM adapter. I can tap the sensor and get ~1v out of it, but when the car is idling and revving it won't go above .02v. Any ideas?
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One quick question about knock sensing - I hooked my Bosch sensor up to the AEM and stuck it on the side of the block. I placed the sensor in the OEM location using the FM adapter. I can tap the sensor and get ~1v out of it, but when the car is idling and revving it won't go above .02v. Any ideas?
You may find the answers to this question in this thread: https://www.miataturbo.net/forum/t33781/
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J_man's answer to that question. Here you go:
Quote:
Originally Posted by stinkonamonkey
You can use a saturn knock sensor for the EMS. Search the AEM forums for details. You have to run a shielded wire to the sensor and mount it to the block using a modified bolt. I've got one installed but I haven't got it working real well yet.
+1. The resonant Saturn sensor is the one he needs.
Flat response sensors won't work.
Quote:
Originally Posted by stinkonamonkey
You can use a saturn knock sensor for the EMS. Search the AEM forums for details. You have to run a shielded wire to the sensor and mount it to the block using a modified bolt. I've got one installed but I haven't got it working real well yet.
+1. The resonant Saturn sensor is the one he needs.
Flat response sensors won't work.
#110
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I posted a bandpass filter and amp for the AEM to be used with the 99 knock sensor.
There was a thread about using said circuit for a Bosch type sensor. I answered there but I don't remember my answer.
The GM resonant sensor center frequency is a bit off from the miata's knock resonant frequency. Those resonant sensors have extremely narrow bands so I don't know how well they would work compared to a flat sensor with a proper bandpass filter.
BTW the Link doesn't have a bandpass filter either based on a schematic I was shown. (Unsure ifi I saw the FM version)
There was a thread about using said circuit for a Bosch type sensor. I answered there but I don't remember my answer.
The GM resonant sensor center frequency is a bit off from the miata's knock resonant frequency. Those resonant sensors have extremely narrow bands so I don't know how well they would work compared to a flat sensor with a proper bandpass filter.
BTW the Link doesn't have a bandpass filter either based on a schematic I was shown. (Unsure ifi I saw the FM version)
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I may have a '99 sensor laying around but I know I have a 2002 sensor. Mazdacomp's site is cocked up so I can't check part numbers, but are the 2001+ sensors similar to the 99/00 sensors?
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Flat response/bosch/wide band knock sensors do work, I use one. It just doesn't work as well as something setup specifically for the miata, or something that outputs up to 5volts like a dedicated filter & amp circuit would.
I can check when I get home Andrew, but I don't think the knock sensor volt moves much when I rev my engine either (using FM supplied bosch sensor from my Link ECU days). But it definitely "spikes" when I get knock. The spike is less than 1 volt but it's still obvious when there's normally a constant 0.x volts. You have my settings to see how much timing it pulls/fuel it adds per volt but obviously there's a bunch of resolution not used when using a bosch sensor wired directly to the box.
EDIT: Sooo a dedicated black box tuned/amplified for use with a Bosch knock sensor will be included in the crank trigger/vvt kit you guys are putting together for us lazy AEM users, right?
I can check when I get home Andrew, but I don't think the knock sensor volt moves much when I rev my engine either (using FM supplied bosch sensor from my Link ECU days). But it definitely "spikes" when I get knock. The spike is less than 1 volt but it's still obvious when there's normally a constant 0.x volts. You have my settings to see how much timing it pulls/fuel it adds per volt but obviously there's a bunch of resolution not used when using a bosch sensor wired directly to the box.
EDIT: Sooo a dedicated black box tuned/amplified for use with a Bosch knock sensor will be included in the crank trigger/vvt kit you guys are putting together for us lazy AEM users, right?
#114
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I had just a Bosch flat response sensor in the past connected to the AEM - it is kinda unusable. It picks the entire frequency range and often there are high level sounds which are not knock frequncy but could fool the ECU.
I currently have the Saturn resonant sensor hooked to the AEM.
Jason says Miata knock frequency is abnormally high - if that's true I'll switch back to the Bosch sensor with his bandpass filter / amp (you have to filter out the proper frequencies and amplify the signal before feeding it to the AEM if using a flat response sensor).
Hey Jason, was your frequency pick based on just that single wav file you posted back then (with a couple of knocks in it)?
Or did you test with a bunch of induced knocking at low, mid and high rpm to confirm that the frequiency is the same over the rpm range at both mild and strong knocking - but you never posted those?
I currently have the Saturn resonant sensor hooked to the AEM.
Jason says Miata knock frequency is abnormally high - if that's true I'll switch back to the Bosch sensor with his bandpass filter / amp (you have to filter out the proper frequencies and amplify the signal before feeding it to the AEM if using a flat response sensor).
Hey Jason, was your frequency pick based on just that single wav file you posted back then (with a couple of knocks in it)?
Or did you test with a bunch of induced knocking at low, mid and high rpm to confirm that the frequiency is the same over the rpm range at both mild and strong knocking - but you never posted those?
#116
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I only tested off-idle knock and found 13 kHz to be the best center frequency.
I would appreciate some knock recordings - I can analyze them, and then I can re-adjust the center frequency of my circuit.
13 kHz is not "abnormally high". I tested some GM Saturn sensors and IIRC they were at 12 kHz IIRC.
I would appreciate some knock recordings - I can analyze them, and then I can re-adjust the center frequency of my circuit.
13 kHz is not "abnormally high". I tested some GM Saturn sensors and IIRC they were at 12 kHz IIRC.
Last edited by JasonC SBB; 03-11-2010 at 04:25 PM.
#117
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I only tested off-idle knock and found 13 kHz to be the best center frequency.
I would appreciate some knock recordings and then I can re-adjust the center frequency of my circuit.
13 kHz is not "abnormally high". I tested some GM Saturn sensors and IIRC they are at 12 kHz.
I would appreciate some knock recordings and then I can re-adjust the center frequency of my circuit.
13 kHz is not "abnormally high". I tested some GM Saturn sensors and IIRC they are at 12 kHz.
I should've said compared to that GM paper often posted about how to calculate the knock frequency knowing the cylinder bore. Following that formula IIRC the Miata engine knock was somewhere around 8Khz.
With that other thread about the electronic det cans group buy, I hope people post knock recordings too sometime soon
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Hmm. John @ J&S posted in the past that the Saturn sensor has lower than 12Khz resonant frequency. No idea whether he tested but IIRC the sensor part info came from him.
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These settings are what I started with. I can run the duty up to 90% and there's no effect on the solenoid. I raised the output limit to 100% since it was being limited at 48 and it still doesn't want to respond. Idling at a steady 11.8-12.0 cam degrees.
#119
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Post a screenshot of the cam #1 template.
Did you look at the parameter screen to see what duty cycle it's actually outputting?
And, if your "cam start" number is correct, it should idle at ~23* cam degrees if you're outputting zero duty cycle.
Did you look at the parameter screen to see what duty cycle it's actually outputting?
And, if your "cam start" number is correct, it should idle at ~23* cam degrees if you're outputting zero duty cycle.
Last edited by JasonC SBB; 03-12-2010 at 06:43 PM.
#120
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J_Man, a super easy way to find the resonant frequency of a piezo sensor is to use a signal generator with 1V or so of output on it. It will act as a loudspeaker. there is a very narrow range of frequency where it gets loud. I posted this a long time ago on MF.
Here I found my thread
http://forum.miata.net/vb/showthread...ight=resonance
Two piezo sensors with the same part number show 11.6 kHz and 8.5 kHz. I have a feeling the 8.5 kHz one got over-tightened and damaged.
If you listen to the recording, you get a descending note, which I would think is because the piston is moving down the cylinder. Which means that bore diameter is only part of the picture.
Also, 13 kHz is exactly one octave above 6.5 kHz ......
Here I found my thread
http://forum.miata.net/vb/showthread...ight=resonance
Two piezo sensors with the same part number show 11.6 kHz and 8.5 kHz. I have a feeling the 8.5 kHz one got over-tightened and damaged.
If you listen to the recording, you get a descending note, which I would think is because the piston is moving down the cylinder. Which means that bore diameter is only part of the picture.
Also, 13 kHz is exactly one octave above 6.5 kHz ......