Rebuild all the salvage Miatas! ASS!
#2421
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Just tried it. No dice. Same issue. Next stop I'll try readjusting the crank sensor and try again, just to be sure. It did seem to rev maybe a little higher this time...
#2422
What motor, VVT or 99 head? What ecu? If MS3X, how are the pots adjusted, and do you have a resistor on any of the sensors? Are every inch of the wires between the ECU and sensor shielded? Are the wires extremely close to the ignition cables? Does the problem occur before the engine is heatsoaked? What is the distance between the crank and crank wheel? Is the crank wheel wobbling at all?
#2423
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What motor, VVT or 99 head? What ecu? If MS3X, how are the pots adjusted, and do you have a resistor on any of the sensors? Are every inch of the wires between the ECU and sensor shielded? Are the wires extremely close to the ignition cables? Does the problem occur before the engine is heatsoaked? What is the distance between the crank and crank wheel? Is the crank wheel wobbling at all?
MS3x
Pots unknown (thought I remembered adjusting them. Need to check)
No resistors
No shielding
Happens cold
Distance unknown. I told Ed to use a business card.
Wobble unknown.
We can get a scope on both sensors and rev to the moon in my garage. That will happen after simple fixes are checked.
If I wasn't also trying to run my turbo Miata at the track 800 miles from home on a cracked exhaust manifold I would have checked most of that by now. I was a little preoccupied
#2424
VVT head.
MS3x
Pots unknown (thought I remembered adjusting them. Need to check)
No resistors
No shielding
Happens cold
Distance unknown. I told Ed to use a business card.
Wobble unknown.
We can get a scope on both sensors and rev to the moon in my garage. That will happen after simple fixes are checked.
If I wasn't also trying to run my turbo Miata at the track 800 miles from home on a cracked exhaust manifold I would have checked most of that by now. I was a little preoccupied
MS3x
Pots unknown (thought I remembered adjusting them. Need to check)
No resistors
No shielding
Happens cold
Distance unknown. I told Ed to use a business card.
Wobble unknown.
We can get a scope on both sensors and rev to the moon in my garage. That will happen after simple fixes are checked.
If I wasn't also trying to run my turbo Miata at the track 800 miles from home on a cracked exhaust manifold I would have checked most of that by now. I was a little preoccupied
#2425
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It's not wobbling.
The composite log clearly shows that it's the cam sensor that loses sync, but it continues to register the crank sensor. I'm a little confused Ian, since the cam sensor has less marks than the crank sensor so it's easy to tell them apart in the log.
Perhaps I'm not understanding something.
And Gordon -- thank you! I appreciate it. It was a lot of fun being out on track with you guys.
I am very, very pleased. This was the first time driving this car in anger, EVER, and it was a gutted rolling shell just 60 days before the event. The last time I tracked a Miata was last September, over a year ago. Early Saturday I was struggling to put down 1:56-1:57 lap times, but got into a groove and dropped a lot of time quickly after that.
Can't wait to get back there and try again.
The composite log clearly shows that it's the cam sensor that loses sync, but it continues to register the crank sensor. I'm a little confused Ian, since the cam sensor has less marks than the crank sensor so it's easy to tell them apart in the log.
Perhaps I'm not understanding something.
And Gordon -- thank you! I appreciate it. It was a lot of fun being out on track with you guys.
I am very, very pleased. This was the first time driving this car in anger, EVER, and it was a gutted rolling shell just 60 days before the event. The last time I tracked a Miata was last September, over a year ago. Early Saturday I was struggling to put down 1:56-1:57 lap times, but got into a groove and dropped a lot of time quickly after that.
Can't wait to get back there and try again.
#2426
I have a hunch it's aggressive filter settings... If you post a screenshot of Ignition Settings => Noise Filtering I'll have a look.
#2427
It's not wobbling.
The composite log clearly shows that it's the cam sensor that loses sync, but it continues to register the crank sensor. I'm a little confused Ian, since the cam sensor has less marks than the crank sensor so it's easy to tell them apart in the log.
Perhaps I'm not understanding something.
The composite log clearly shows that it's the cam sensor that loses sync, but it continues to register the crank sensor. I'm a little confused Ian, since the cam sensor has less marks than the crank sensor so it's easy to tell them apart in the log.
Perhaps I'm not understanding something.
Back when my car was throwing sync errors every 15-20 minutes last year, the composite log never showed anything strange. I've come to the conclusion that the log is a useful tool but should not be assumed to always be definitive. As Reagan said, "Trust, but verify", and in this case repeating the 6K RPM test after fixing the crank pulley was verification.
--Ian
#2428
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I. am. So. Pissed right now.
my camera recorded ONE session. Even though I set it to record the last 3 sessions each day, it got only one. it looks like a sunday session; praying it was the last one. Not sure yet. Ugh. sooooo disappointing.
my camera recorded ONE session. Even though I set it to record the last 3 sessions each day, it got only one. it looks like a sunday session; praying it was the last one. Not sure yet. Ugh. sooooo disappointing.
#2429
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The logs are "events the ECU saw", not "a history of voltages seen on the pin". The cam sensor won't show in the logs if the interrupt masking drops the edges, and the way the code is written (kinda hacky at a low level) can make it unintuitive to diagnose when it goes wrong. We spent a long time staring at it while diagnosing Ian's setup.
I have a hunch it's aggressive filter settings... If you post a screenshot of Ignition Settings => Noise Filtering I'll have a look.
I have a hunch it's aggressive filter settings... If you post a screenshot of Ignition Settings => Noise Filtering I'll have a look.
Also, for the video... the session it got was the last session with the best lap! Uploading to YouTube now...
#2435
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I actually did. One of the first things I said when we saw the cam signal was disappearing. But we were at MRLS and it was dark at the campsite, and I didn't feel like pulling the ECU and doing stuff.
I also thought that you had to measure voltage when you adjusted them, instead of just turning them a set number of times.
I also thought that you had to measure voltage when you adjusted them, instead of just turning them a set number of times.
#2436
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Lol. RIIIIGHT. I bet you're super jealous of my startup squeal and, uh, smooth cluch engagement and stuff.
Thanks for coming out. Was hoping that that was the solution, but glad we could at least eliminate that. Will probably play with megasquirt pots tomorrow but for now... Turn down the rev limit.
Thanks for coming out. Was hoping that that was the solution, but glad we could at least eliminate that. Will probably play with megasquirt pots tomorrow but for now... Turn down the rev limit.
#2438
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The potientiometers are bias resistors that are used to set the zero crossing threshold of the VR conditioner chip. Takes a 0-5 volt signal and converts it into on and off.
#2439
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I feel like my MS3-Basic does not have these magical pots. I'll have to check next time I have it open. I don't remember having to adjust anything, or instructions to do so.
I brought my Fluke and a 12v wall wart out to MRLS so we could play with Eds MS, but I think we got distracted.
I brought my Fluke and a 12v wall wart out to MRLS so we could play with Eds MS, but I think we got distracted.