seth1001 Posted March 10, 2011 Share Posted March 10, 2011 Hey fellas, I just finished wiring up my MS3 V3.0 into my 1980 280zx N/A...and needless to say it's not going too well so far. I'm gonna break down the issues into phases so it's easier to see the timeline of problems. Keep in mind that at some points there were some obvious problems but they were minor in nature so I was willing to move forward just to see if I could get the thing to idle. Phase 1: Before attempting to start Here my main issue was the coolant temperature sensor. I just used the stock sensor but I had trouble calibrating it. The values I input from this thread: http://forums.hybridz.org/index.php/topic/57800-280z-coolant-temp-sensor-values-for-easytherm/page__p__527871__hl__%2Bcoolant+%2B280z__fromsearch__1#entry527871 did not work right...it was reading at like...215 degrees F when it should have been around 60. So I got out the FSM and input the values from the graph for the 1980...still didn't come out quite right. So then I tweaked the bias resistor value until I got the megasquirt to read somewhere around 60...not the best approach but again...I just wanted to see if I could get the thing to start. Anyway...does anybody know what the values should be?...Or should I just get a new sensor from autozone? Phase 2: First start attempt No rpm indication. I figured it was something stupid...like...I hooked up the wrong wire to the negative terminal...which I'm pretty sure I did. I went back at looked at the diagram on this link: "http://www.msextra.com/doc/ms3/hardware.html#wiring" then I saw that it was pin36 that went to the coil (-)...but the wire colors didn't match...I saw on another drawing that it was a grey wire...so I thought the grey shielded IGN wire was the thing to hook up there...anyway...I swapped it to the pin 36 wire and tried again Phase 3: Second attempt When I first turned the key to IGN...the fuel pump kicked on and wouldn't go off...seemed weird so I killed the IGN and clicked it back on...pump went off...so I guess that's good. Cranked it a little to see what would happen...NO RPM indication but the engine fired and started idling...albeit quite roughly...I think it may have been burning fuel already in the cylinder cause without RPM the megasquirt shouldn't be firing the injectors at all...anyway...then the engine died and the garage stunk of gas from the rich burn and the fuel pump refused to kick on again...it might be broken...never got any RPM indication...also the power to the MS kicks off if I crank too long. Which makes sense because even in modern cars pretty much everything loses power when the starter is running...so I'm a little confused as to how its supposed to work while starting. Anyway, I've got the board all set up for coil negative rpm and I got it to work with the stim. In order to get it working I had to jump the D2 diode because the stim didn't have enough voltage to push through it. I pulled the jumper off when I put it in the car because it's my understanding that that's what you're supposed to do. Any thoughts on the RPM not showing up? I wired the power for the MS and my wideband sensor to the ignition switched wire going to Fuel Pump relay #2...any thoughts on that?...Is it...good? I'm really not sure...I couldn't really find any recommendations on where to get power so I just stared at the wiring diagram in the FSM until I found something that seemed reasonable. So that's about it...I'm fairly stuck right now...don't really know what to try at this point. I might think of something eventually but it would surely move quicker if you guys could point me in the right direction. Thanks. PS. Sorry it's a long post Quote Link to comment Share on other sites More sharing options...
mobythevan Posted March 13, 2011 Share Posted March 13, 2011 Megasquirt needs power during cranking and running. This is a very common mistake to only have power running and lose it during cranking, fix that first. Make sure megatune or tuner studio is communicating with megasquirt before cranking over the engine. See that temp gauges and other stuff are working, then see if you still show no rpm. Quote Link to comment Share on other sites More sharing options...
seth1001 Posted March 13, 2011 Author Share Posted March 13, 2011 How do I do that?....What should I wire it to? Quote Link to comment Share on other sites More sharing options...
mobythevan Posted March 14, 2011 Share Posted March 14, 2011 You should look at the wiring diagram for your car and decide which wire meets these conditions to power megasquirt. I don't know off hand. You will want to become familiar with reading your wiring diagram anyway or your megasquirt install will become very tough to deal with. Quote Link to comment Share on other sites More sharing options...
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