HAs anyoen with the tach noise altered or installed the ED capacitor? The V2.2 has this installed as built but the v3.0 leaves the cap out unless you have noise issues. Now if you have noise with the cap installed you can slowly raise the value by .001uf but do not go larger than .1uf.

I was doing to some verifying in the v2.2 instructions since i am building a MS for a different type of car and Noticed the comments regarding the operation of the Ed capacitor. So this made me wonder why its not installed in the v3.0 (c12). The v3.0 assembly does make note of the noise that can be found in the tach signal and that you can install the cap and alter its size just liek the v2.2 assembly instruction.

This may be the whole key to why the v2.2 doesnt have a problem and the v3.0 had tach noise.

has anyone done this?

Does anyone have a v3.0 installed with this issue that can install the cap or send me the ECU to install it so you can try it?

Terry

good find, Ill take a looky.

Terry... does this mean that you've been able to verify the tach noise problem that I was having with Casey's V3 board? If so, that's good. I gave up on the V3 board after that fiasco.

If my car didn't hate me so much, I might be able to help you out some with this one since I am indeed using one of your V3 boards. Either way, great find... :thumbsup

Originally posted by dougie2
Terry... does this mean that you've been able to verify the tach noise problem that I was having with Casey's V3 board? If so, that's good. I gave up on the V3 board after that fiasco.

Doug I am not positive but this is the difference in the input section of the board.

Perhaps Doug, if you will have time this month I can order/build a V3.0 board and you can test it. Since we know your car with the 2.2 doesnt have any issues and with the v3.0 installed it does. That would leave the only variable being tested to be the MS.

Terry

Originally posted by Star Turbo Talon
Perhaps Doug, if you will have time this month I can order/build a V3.0 board and you can test it. Since we know your car with the 2.2 doesnt have any issues and with the v3.0 installed it does. That would leave the only variable being tested to be the MS. Terry

Terry,

I can test a v3.0 if you'd like, no problem. My car is running again and I can also test on Casey's car. Just hit me up if you want to do that.

Let me order up a kit and get it built. Looking into testing it in a couple weeks.

Terry

The Cap doesn't do much. it just smooth out the waves a bit when the RPM signal comes in. I tried different size of Cap, and the Tack is still there (before I fix it)
If you do a search, me and 2 others was struggling with the tack spike a month or two back.
We got a solution already by doing VR and Hall circuit.
Hope that helps.
Gil

The VR doesnt work for everyone. What size Cap did you go with?

I tried from 0.001uF up to 0.1uF doesn 't do a single bit

I also tried playing with capacitors on that circuit a while back with little success. I still think the best way to solve it should be with better software... something that would be more flexible when looking at the signal coming in. Some type of algorithm that knows what the wave should look like and have a good guess where the next edge should be coming in at, based off how fast RPM's could possibly change between cycles. I bet you could easily "throw out" a good chunk of spikes that way.

Has anyone ported the -extra code to C yet?

Trying to clean the noise via software would just be a bandaid if it was physically possibly to intrepret the rpm during the noise. I really with I had an oscilloscope to really hunt down the EXACT cause of the problem.

When I had my scope I found a lot of noise coming in right around the ignition event. I never had this tach spike issue with the 2.2 board, maybe there is some crosstalk somewhere between traces.

The best workaround for that is to shield the crap out of everything. I'm talking coax everywhere. Adding software fixes couldn't hurt, either. Although I don't know much about the current state of the decoder, I'm sure there is room for improvement on a better definition on what is a tach spike and what is a rising or falling edge coming in from the sensor. I don't want to learn a new language (assembly) to fix it. A port of the -extra code to the MS2 platform (C language which I can code in) is LONG OVERDUE. The handful of developers are just too goddamn lazy to do it, mainly because they are not being paid and do it and all of this gets done in their spare time. I would be dragging my feet on it too if it was my "problem".