Miata Turbo Forum - Boost cars, acquire cats.

Miata Turbo Forum - Boost cars, acquire cats. (https://www.miataturbo.net/)
-   MEGAsquirt (https://www.miataturbo.net/megasquirt-18/)
-   -   99-00 MS-IIx Initial tuning issues, Logs... (https://www.miataturbo.net/megasquirt-18/99-00-ms-iix-initial-tuning-issues-logs-15055/)

AbeFM 12-31-2007 09:16 PM

huh huh.. uh huh huh... He said... "lube". huh.


Yeah, well, I'll have to figure something out. This always happens on the holidays. :-)

Right now I'm trying to figure out why my fan output isn't working. I've found a dumb mistake or two, but even after fixing it's off. Go figure. Sandwhich time, then thinking.

Joe Perez 01-06-2008 01:00 PM

Ok, it's a week late, but I *knew* I wasn't that crazy. This is the circuit we drew on the wall at my place when you were here. Notice the location of the pullup 4.7k resistor relative to the series 4.7k resistor. The series resistor should be between the pullup and the base, not between the pullup and the sensor. This circuit will work.

http://img166.imageshack.us/img166/6306/igninputrm2.png

AbeFM 01-06-2008 01:24 PM

Now that's funny - cause that's what I had. And it wasn't working.

Little did I know there were other issues. Plenty of them - the sensors weren's switching. In the mean time, I'd convinced myself is was the sensor and not the input that needed the help, and moved it over.

I guess I'll try putting it back, though everything is beautiful now, so I'm not sure why I would.

When I had it the way of the drawing, and dropped the resistance of the pull up, it stopped working. (1k, 1k).

Now it's 10k pull up, 1k between pull up and sensor, and the graphs are beautiful. You think I should change it (I was going to finalize the soldering today)

I'm not sure 4.7k will work, if you check the pictures I posted on the web, when there's 2k of resistance, the crcuit never hits a stabls voltage.

AbeFM 01-06-2008 01:39 PM

I think I'm going to try to hold the crank sensor offset 20* so it's pulses line up with what the MS expects. They are telling me to flip the polarity of one of my inputs on the forums, but the MS syncs fine on the JimStim when it's polarities match mine - only it's phase is off.


I need more hands/brains here. My roomate has both but is unreliable. :-)

<edit> 21.818 degrees.

AbeFM 01-06-2008 08:18 PM

I could only offset it by ~30*, but that works, it syncs great. My bracket is way too temporary to run around on it, but I bet it would work.

Now I gotta figure out why the car wigs out when I power the wideband. I must have fubar'ed the wiring on it. Not sure how, but yeah....


Also, can someone with a 99+ tell me what's up? I get +12/open/ground on the 3 pins of the cam sensor (which puts out a 0-5v signal) and Arga was saying there's only a 5V feed to the crank sensor (which puts out like 800 mv).

All very weird....

cjernigan 01-06-2008 09:42 PM

I can probe those when i get home. It'll be a while though.

Joe Perez 01-06-2008 11:19 PM


Originally Posted by AbeFM (Post 194689)
Also, can someone with a 99+ tell me what's up? I get +12/open/ground on the 3 pins of the cam sensor (which puts out a 0-5v signal)

The cam and crank sensors do not output voltage, they sink voltage. Both are open-collector devices, hence the pullups on the MS board.

On the cam sensor, terminal A (W/R) is the +12 supply to power the sensor, terminal C (B/L) is sensor ground, and terminal B (GY/R) is the open collector output. When the sensor is "off" then terminal B floats. When the sensor is "on" then terminal B conducts to ground.

AbeFM 01-07-2008 04:07 AM

Er, yeah, I just meant the supply to the sensor - which is, as far as I'm concerned, a black box for syncing current. All I really was curious about was the supply to them - they are 3 pin devices, and I just wonder if something went weird with my wiring, since Frank says he has 5v on his crank sensor (I haven't measured mine, but my cam gets switched 12V).

I think I have real grounding issues, actually, a number of things get weird when I'm not careful with it. Or maybe my 12V supply is lacking, but I doubt it. I dunno. Both the recent COP playing and the WBO2 have made the computer act a little funny - I figure it issues with the sensors are a symptom. Maybe I'll try to run another ground to the block, I just figured the ground in the ECU harness would be good - and I've got at least 4 16 guage grounds. Only one 16 guage +12 supply, though. The pin has two wires off it, one feeds my MS, one the WB.

Joe Perez 01-07-2008 11:04 AM


Originally Posted by AbeFM (Post 194898)
I just wonder if something went weird with my wiring, since Frank says he has 5v on his crank sensor (I haven't measured mine, but my cam gets switched 12V).

According to the wiring diagram, both the cam and crank sensors are supplied with +12 on the white/red wire which comes from ye olde' main relay. This circuit is independent of the ECU- it closes when you turn the key.


I just figured the ground in the ECU harness would be good - and I've got at least 4 16 guage grounds. Only one 16 guage +12 supply, though. The pin has two wires off it, one feeds my MS, one the WB.
That ought to be adequate. The WB is going to be the primary consumer of power- no idea how much, but easy enough to measure. The MS is required to sink a fair amount of current to ground (from the injectors, EBC, IDL, etc) but it consumes relatively little current from the +12 input.

AbeFM 01-07-2008 01:00 PM


Originally Posted by Joe Perez (Post 194992)
That ought to be adequate. The WB is going to be the primary consumer of power- no idea how much, but easy enough to measure. The MS is required to sink a fair amount of current to ground (from the injectors, EBC, IDL, etc) but it consumes relatively little current from the +12 input.

Yeah - those were my thoughts. Which is why I wired it that way. The WB takes power, and now returns it, at the pins on the boomslang, somehow moving it 6 inches down a piece of wire makes everything behave, which tells me it's borderline. I really should move it to the block, but then I'll have to run a line from the ECU to there. Maybe I'll compramise and run a strap to the nearby under-dash metal. The batter voltage drops 0.2V when I hook up the WB. The supplied documentation says it requires a 5 amp fuse.
Anyway, I really wonder if my sensors acting funny is a ground thing.

But, the big news for today is the car syncs when I move the crank sensor, so I've got to dig into the code. Well, I guess I should also flip the signal from one of the sensors - apparently they need to be both "upgoing" or "downgoing", not mixed (as the raw sensor output is). So I'm trying to decide how to do this, but really, the car syncs with the offset crank trigger.

http://abefm.smugmug.com/photos/240509038-L.jpg


All times are GMT -4. The time now is 12:19 AM.


© 2024 MH Sub I, LLC dba Internet Brands