MS2 Not seeing RPM at startup intermittent
#1
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So I have recently got my 99 Miata running on ms2 firmware 3.4. I have been having the problem of when I try to start the car the MS does not see the RPM. I changed some ignition settings and cranking RPM and it started reading RPM every time and started yesterday. I go to start the car this morning and experience the same issue no RPM signal in MS. If I keep trying to start it maybe 1 in 20 times the RPM sync will light up for 1 sec go off and not turn the car on. I am not sure where to go from here. Any help would be greatly appreciated.
#6
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I was wondering if there were POT setting for ms2 diypnp like this one.
https://www.diyautotune.com/product/...assembled-kit/
I have seen a few responses from people about POT settings but they always refer it to ms3x.
If so i'm guessing that could be my problem? Just weird that it worked before without having to do anything inside the mega squirt.
https://www.diyautotune.com/product/...assembled-kit/
I have seen a few responses from people about POT settings but they always refer it to ms3x.
If so i'm guessing that could be my problem? Just weird that it worked before without having to do anything inside the mega squirt.
#16
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So I did a few more things. I took the ground from the intake manifold and put it right to the frame rail and sanded off the paint for a better connection. I changed the cranking RPM to 300 and it seemed to be lighting up the RPM SYNC light more often then it usually does. But still no start. I took another log and going to attach them here. If anyone could give me some other suggestions on what to do. I may run a wire from the cam sensor right to the MS and see if that is an issue. Is there anything in the megasquirt I can check with a multi-meter to verify that it is correct?
#18
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Update. I checked the orientation of my factory timing wheel that I had to put in due to the though the 5x racing wheel was not lined up perfect. And come to find out the OEM wheel is reversed. In the logs it shows no cam signal but maybe if the crank is not triggering when it things it should it will not show a cam input? Well when I get home I am going to switch it around and hope I get some reading and or get the damn thing running again.
#19
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The issue is definitely with your cam signal. The signal your log is showing is clearly a crank signal. Have you confirmed continuity from sensor to MS?
In order to further troubleshoot if the error is within the MS or signal going into the MS, you could swap cam and crank signal lines and log crank and cam. If all the sudden your crank signal shows up where your cam is supposed to be, the problem is the cam sensor or wiring. If the cam shows up where the crank is supposed to be, it's a problem inside the MS.
In order to further troubleshoot if the error is within the MS or signal going into the MS, you could swap cam and crank signal lines and log crank and cam. If all the sudden your crank signal shows up where your cam is supposed to be, the problem is the cam sensor or wiring. If the cam shows up where the crank is supposed to be, it's a problem inside the MS.
#20
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So I checked the wheel and all was good. I then de-loomed the wire to the cam and crank sensor and separated them as far apart as I could and it seems to start every time. So now that I can get it started it runs very bad. Does anyone have a good start up tune for a 99 miata? I can find a few but they all have different settings. Or is there something I need to do to get the car to run smoothly.