RPM signal

PopKorn78 · Post by **PopKorn78** » Mon Mar 23, 2015 10:58 pm

Hi guys,

I'm trying to get a RPM signal for my RCP. The car is a Civic with a B16 engine with a distributor. What wire should I get the signal from?

I have a CoilX on hand if needed.

Post by **brentp** » Tue Mar 24, 2015 9:34 pm

I'd first try the white wire connected to the PGM-FI ECU (upper right of the diagram).

Do keep us posted on this!

PopKorn78 · Post by **PopKorn78** » Wed Mar 25, 2015 1:02 am

Thanks Brent,

First, I had the wrong distributor wiring.

I have tried with the YEL/GRN and BLU, but RCP reads 0. On both test, I had the coilX installed. I tried the BLU test straight without the CoilX, but no change.

I have a tach tap in the BLU that works fine.

Voltage on both wires is 10.5v, there is no peaks that I can see on the multimeter, I don't have a scope yet.

Should I try to get to the WHT/BLU from the COIL to the ICM in the distributor on the negative?

Post by **brentp** » Wed Mar 25, 2015 2:30 am

* try yellow/green without CoilX. That might work.

PopKorn78 · Post by **PopKorn78** » Wed Mar 25, 2015 10:13 pm

Still no signal.

It was suggested on another forum to use the Crank Position signal that gives 1 pulse every rotation. Is there something to check or a setting to ajust before trying? I'm a little scared of frying the RCP by trying all kind of stuff.

Post by **brentp** » Wed Mar 25, 2015 10:45 pm

Yes - you can try the crank position signal output safely.

One thing to check, make sure you don't have any other channels defined as "RPM" - specifically the OBD-II channels - that will block the value from updating.

Keep us posted on what you find!

PopKorn78 · Post by **PopKorn78** » Thu Mar 26, 2015 2:45 am

Still no luck. I had the OBDII RPM channel enabled. I removed it and redid all the wires again, with and without CoilX, but no signal again.

I'm waiting for a scope to try to help you so we can figure this out, but if you have any other idea to try, let me know please.

Here are some links that might help you out.
http://www.diyautotune.com/tech_article ... _acura.htm
https://www.hondata.com/forum/viewtopic.php?t=7759
http://www.team-integra.net/forum/17-au ... butor.html

Post by **brentp** » Thu Mar 26, 2015 3:07 am

You had OBD-II enabled - Also make sure you also remove any OBDII channels assigned to RPM, because that will still affect things, even if OBD-II is turned off.

If not, let us know when you get the 'scope.

PopKorn78 · Post by **PopKorn78** » Fri Mar 27, 2015 12:27 am

Good news, I found the signal, it's from the yellow/green wire from the distributor set to 2 pulse per rev. It worked after I flashed the firmware to reset the RCP. It looks like eventho I disabled the OBDII channel, it was still blocking it.

But I have another issue. I have a reading in the raw page of the dashboard on RPM2, but on the analog page, I get nothing. It did worked the first time, but when I cam back to the car after 1h, the RCP App had shutdown on my pc and since then, nothing.

PopKorn78 · Post by **PopKorn78** » Fri Mar 27, 2015 12:45 am

I don't know what I've done, but I got it now.

But, AGAIN, the warning does not work. When turn the car ignition ON I get a reading of between 70000 and 90000. When I turn the ignition OFF, I get a reading of 294090. I only get a reading of 0 when I start the RCP App.

PopKorn78 · Post by **PopKorn78** » Fri Mar 27, 2015 1:01 am

Forget what I've posted ealier, I was so exited that the RPM worked, the I've set the low and high limit at the same ragne.

The only clarification I would like is about the reading I get when the car is not running. Does it matter? I thought it might be voltage peaks, so I tried with the CoilX, but I don't get any reading.

When this is all sorted out, I will make a post for the Honda guys with the how to's so that another noob like me does not have to make you go crazy with lame questions

Post by **brentp** » Fri Mar 27, 2015 1:55 am

Hey, glad you got it working! Can you clarify your last statement about the car that isn't running?

Also - most importantly - could you take a pic of the wire you tapped into so the next person can identify it on their car? That would be a great addition to our wiki.

PopKorn78 · Post by **PopKorn78** » Fri Mar 27, 2015 2:44 am

I mean, when I switch the ignition ON and engine not running, I get a anywhere from 20k to 90k.
When I start the engine, I get a normal RPM reading.
When I switch the ignition OFF, I get a reading of 204090.

Tommorow I will check the raw voltage reading.

Post by **brentp** » Fri Mar 27, 2015 5:27 am

Ah, I see. That is an artifact of a glitch that occurs on the RPM line when the engine stops running. We'll see what we can do with that.