VVT swap with Rev MS3, no start
#1
Cpt. Slow
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VVT swap with Rev MS3, no start
Sounds familiar, right?
'93 chassis with MS3basic and VVT swap. Only thing interesting is the Tomei intake and exhaust cams plus SPM damper and proprietary 32-2 wheel. Wired per VVT megathread, and I've tested injectors A-B-C-D as 1-3-4-2. Coils A and B are firing the VVt coils. I'm getting cam and crank signal but lots of sync errors. Occasional sputters of life, but no matter what req fuel and/or throttle I throw at it it won't do anything but sputter. Let me know if you see anything wrong!
'93 chassis with MS3basic and VVT swap. Only thing interesting is the Tomei intake and exhaust cams plus SPM damper and proprietary 32-2 wheel. Wired per VVT megathread, and I've tested injectors A-B-C-D as 1-3-4-2. Coils A and B are firing the VVt coils. I'm getting cam and crank signal but lots of sync errors. Occasional sputters of life, but no matter what req fuel and/or throttle I throw at it it won't do anything but sputter. Let me know if you see anything wrong!
#2
SADFab Destructive Testing Engineer
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Sounds familiar, right?
'93 chassis with MS3basic and VVT swap. Only thing interesting is the Tomei intake and exhaust cams plus SPM damper and proprietary 32-2 wheel. Wired per VVT megathread, and I've tested injectors A-B-C-D as 1-3-4-2. Coils A and B are firing the VVt coils. I'm getting cam and crank signal but lots of sync errors. Occasional sputters of life, but no matter what req fuel and/or throttle I throw at it it won't do anything but sputter. Let me know if you see anything wrong!
'93 chassis with MS3basic and VVT swap. Only thing interesting is the Tomei intake and exhaust cams plus SPM damper and proprietary 32-2 wheel. Wired per VVT megathread, and I've tested injectors A-B-C-D as 1-3-4-2. Coils A and B are firing the VVt coils. I'm getting cam and crank signal but lots of sync errors. Occasional sputters of life, but no matter what req fuel and/or throttle I throw at it it won't do anything but sputter. Let me know if you see anything wrong!
#7
SADFab Destructive Testing Engineer
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So the issue I see is the crank sensor is going low too many times. It looks like noise. But this causes the megasquirt to think that there are too many crank pulses. Which makes you lose sync.
See how it goes low for a second there? It shouldn't. And thats why you get the loss of sync at the end, because it counts 35 pulses instead of 34.
So I say swap with a known working crank sensor, and a smaller gap.
See how it goes low for a second there? It shouldn't. And thats why you get the loss of sync at the end, because it counts 35 pulses instead of 34.
So I say swap with a known working crank sensor, and a smaller gap.
#10
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I just counted your log. The miss is at the same place each time. its the 12th tooth from the gap. If that matches up with your count I'm 90% sure thats your problem.
If you close up the gap you might be able to get past it. But I would definitely be getting a new ring.
If you close up the gap you might be able to get past it. But I would definitely be getting a new ring.
#12
Cpt. Slow
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Dammit, that means pressing the pulley off while in the car. Booo.
Just did a log with 10 cranks, it's there on all 10, and yeah, in the same place. Lemme count where it is...Yup, once the 'bad' tooth passes the sensor, there's 11 good teeth and then the gap.
Just did a log with 10 cranks, it's there on all 10, and yeah, in the same place. Lemme count where it is...Yup, once the 'bad' tooth passes the sensor, there's 11 good teeth and then the gap.
#19
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An OEM wheel is incompatible with this damper. This problem could have occurred with a 4 tooth wheel just as easily. You are making a blanket statement that is just false.
#20
We have run the proto 36-2 wheels for many hours under many adverse conditions on our dampers without issue. FM has many customers on their wheel for the ATI damper without issue. Superior to a 4T in every way. This one however, appears to have a manufacturing defect. Unrelated to the design configuration. A defect in an aftermarket 4T would have the same problem. We'll get it sorted out for Josh ASAP.
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