deuce8ernerozero Posted August 11, 2013 Share Posted August 11, 2013 (edited) Okay guys im totally stumped. The car is a stock 1977 280z with a n47/n42 and stock distributor. I am attempting to megasquirt it v3.0 board msns-e 029y4. I cant get the vr sensor to read rpms or better yet i cant get tuner studio to see rpm while im cranking. I built this board myself, everything looks good. Both trim pots are 18+ turns ccw. Ive wired the vr sensor backwards nothing. The only way to get that rpm gauge to move is to short the sensor and tap the connector together. I dont own a scope but i do have a multimeter. I dont have a stimulator but theres one in the mail, It will be here soon. I have no idea whats going wrong, As far as i know it should be triggering. Please help. pictures of the board are attached. thanks Edited August 11, 2013 by deuce8ernerozero Quote Link to comment Share on other sites More sharing options...
skirkland1980 Posted August 11, 2013 Share Posted August 11, 2013 What are your trigger settings? Quote Link to comment Share on other sites More sharing options...
deuce8ernerozero Posted August 11, 2013 Author Share Posted August 11, 2013 Like, under spark settings or outputs and codebase? is there another way to upload my .msq? it wont let me attach it. Quote Link to comment Share on other sites More sharing options...
skirkland1980 Posted August 11, 2013 Share Posted August 11, 2013 Send your msq to a compressed zip folder then you can upload it here. Quote Link to comment Share on other sites More sharing options...
deuce8ernerozero Posted August 11, 2013 Author Share Posted August 11, 2013 I think it worked. I've never had to zip anything before New Folder.zip Quote Link to comment Share on other sites More sharing options...
skirkland1980 Posted August 12, 2013 Share Posted August 12, 2013 Ok cool. I can look at it tomorrow. Or you can send a message to websales@diyautotune.com also. I had better luck turning the trim pots clockwise though. Matt would ask if you're getting rpm in the stim first. Quote Link to comment Share on other sites More sharing options...
Metro Posted August 12, 2013 Share Posted August 12, 2013 Your board looks good. As for software settings, there's really only one: under ouputs and codebase select MSnS^ as your distributor type. Since you said you built this yourself, you should go over all the instructions for the VR conditioner. I'm not sure guide you used, but the manual on the main MS site is helpful for checking your install step by step as you build each circuit. Go to step 51 where it talks about the VR circuit and double check that everything was installed, diodes are orientated correctly, and transistors legs aren't bridged with solder. In my experience VR sensors don't need any adjustment to pick up the RPM signal when cranking, but you can try adjusting your trim pots. Usually I've only had to adjust the pots to fix noise at higher RPMs. Turn both pots all the way counterclockwise until they click or you feel the screw slide. It sounds like you already did this, but just saying. I would start adjusting the bottom pot half a turn at a time and if you still haven't seen any rpm reset the bottom pot and start moving the top pot. The top pot has more to do with the shape of the signal and the bottom is more for noise filtering. You would need an oscilloscope and knowledge of what it's showing to set these perfectly, which is beyond me. It might be helpful to take your distributor out and just spin the shaft instead of constantly cranking the motor over. I'm assuming the dizzy is what was used previously to MS and it's in good working order. You might want to check the air gap for the sensor anyway. Connect a multimeter to see if it's creating AC voltage when you spin it. Quote Link to comment Share on other sites More sharing options...
deuce8ernerozero Posted August 12, 2013 Author Share Posted August 12, 2013 Yeah. I believe the software is set up correctly. Msns is the only box checked on outputs and code base. Q22 and q23 are very clean looking. Diode orientation is correct.. I figured having both pots ccw would be as sensitive as it could be. I'll tweak them next time I can. I need it to dry up first. It's been a very wet summer. As for the distributor. Yeah the car was running before I gutted the toilet flapper efi out of it. I have a stimulator in the mail so I can diagnose the board. I never checked the air gap. I'll check that next time I'm tinkering with it. I never thought to check book volts at the sensor. I could rule out the sensor that way. Thanks Quote Link to comment Share on other sites More sharing options...
deuce8ernerozero Posted August 24, 2013 Author Share Posted August 24, 2013 Got the stimulator or it together in 15 minutes. Everything is perfect. Except my idle valve isn't working. But that's expected. Q4 gave me the most trouble. It turns out a drained old battery that's turning a starter will turn MS on but will make it act funny. Bench power 13v-rpms. wore out 9v ~the same output like 6v-7v output-no rpms. So, it's new battery time. I'll keep you guys updated. Thanks Quote Link to comment Share on other sites More sharing options...
deuce8ernerozero Posted August 24, 2013 Author Share Posted August 24, 2013 Got the stimulator or it together in 15 minutes. Everything is perfect. Except my idle valve isn't working. But that's expected. Q4 gave me the most trouble. It turns out a drained old battery that's turning a starter will turn MS on but will make it act funny. Bench power 13v-rpms. wore out 9v ~the same output like 6v-7v output-no rpms. So, it's new battery time. I'll keep you guys updated. Thanks Quote Link to comment Share on other sites More sharing options...
deuce8ernerozero Posted August 24, 2013 Author Share Posted August 24, 2013 Got the stimulator or it together in 15 minutes. Everything is perfect. Except my idle valve isn't working. But that's expected. Q4 gave me the most trouble. It turns out a drained old battery that's turning a starter will turn MS on but will make it act funny. Bench power 13v-rpms. wore out 9v ~the same output like 6v-7v output-no rpms. So, it's new battery time. I'll keep you guys updated. Thanks Quote Link to comment Share on other sites More sharing options...
deuce8ernerozero Posted September 14, 2013 Author Share Posted September 14, 2013 I put a fresh battery on the car and it started right up, but it seems to be off time a good bit. The motor kicked back the second time i cranked it and it has some dieseling sound while idling. It doesnt want to idle any higher than 600rpm and wants to die without throttling, the air adjustment screw will not change the idle. That and theres a big cloud of nasty old gas smelling fumes coming out of the exhaust. i picked up a set of plugs a step hotter to resist fouling while im tuning it. i also am draining the old gas out today before i try anything. Is it said to put the trigger offset at 60 for a z that hasnt had its distributor moved from the factory spec of 10 degrees? I saw that somewhere. Anyway, i got a timing light and im going to try to time it. Do i need to turn off the megasquirt to have my changes to the trigger offset be effective? Quote Link to comment Share on other sites More sharing options...
Metro Posted September 15, 2013 Share Posted September 15, 2013 Is it said to put the trigger offset at 60 for a z that hasnt had its distributor moved from the factory spec of 10 degrees? I saw that somewhere. Anyway, i got a timing light and im going to try to time it. Do i need to turn off the megasquirt to have my changes to the trigger offset be effective? You can adjust the trigger angle with the engine running. You'll want to verify your timing by locking your advance to 10 degrees by setting "fixed angle" to 10. Then adjust your trigger angle until your timing light reads 10 degrees. The 60 degree number you see floated around is for the L28et's CAS or optical distributor. MS needs a trigger angle that is either 10 degrees higher than your maximum spark advance (50 degrees for example) or under 20 degrees to enable "next cylinder" mode. When I used my 76 VR distributor I had to adjust the mounting plate for the VR sensor to get a usable trigger angle. After adjusting the plate (it's in the FSM) I was able to get a trigger angle around 15 degrees. But when I was using a GM 4pin HEI module, my trigger angle was around 120 degrees. You will always want to verify the trigger angle for yourself. Quote Link to comment Share on other sites More sharing options...
deuce8ernerozero Posted September 15, 2013 Author Share Posted September 15, 2013 Thanks, I'm going to see if I can work with it tomorrow. I found out the tdc Mark is gone off the damper. I'm gonna see if I can find it again this time with a high powered flashlight. Did you ever have this problem? Quote Link to comment Share on other sites More sharing options...
SleeperZ Posted September 20, 2013 Share Posted September 20, 2013 The timing marks should be physical grooves, and can be repainted once you find them. Quote Link to comment Share on other sites More sharing options...
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