Question for V6 ppl that have the S-AFC. Please help!!

[Fishboy55]

What pin on the PCM did you guys tap for RPM signal. I used pin#45, crank position sensor, but it's not a clean signal. I can't find the RPM wire at the PCM in the Service manual. Thanks for your help.

Chip

[SuperchargedGTZ]

i am not sure what was the pin that RIPP tapped the RPM signal with. you can call them, but no matter what pin you tap you are going to get a jumpy signal. if it bothers you that much you really need to get the rpm satchmo fix from club 3G.

i didnt do anything about my signal. Ross at RIPP actually tuned with the jump signal in mind, which is why we tuned up to 8000 rpm. but that doesnt matter now, because my car is going there this weekend for the BB and some other upgrades...hehehe

TO DONATE FUNDS PLEASE SEND $$ BY MONEYORDER....UUUGGGHHH

:scary:

[Auto-9]

The satchmo fix I sold Chip did nothing for his signal cleanup or so I was told. I dunno if somehow he hooked it up wrong despite following the directions exactly or if the Galant somehow differs from the Eclipse (not that I've seen comparing the two manuals but you never know).

[Fishboy55]

'Tis true Peter. That fix didn't work (and yes, I hooked it up right) and neither did the other fix from club3g with the 1M ohm potentiometer. The signal still bounces like hell, which causes the car to run like crap. So I'm thinking PAEXi might be right about the AFC not being compatible with our cars...

[JiP]

Before I found the tach line on my 7g i4, I had the afc wired to the crank sensor it worked fine for me, i guess to much electrical noise with the v6.

If you cant find what pin on the ecu you could just tap the tach signal at the coilpacks in the engine bay.

May I ask how you know the signal isnt clean? Whats your afc doing that makes you think this?

[Auto-9]

<div class='quotetop'>QUOTE(JiP)</div><div class='quotemain'>Before I found the tach line on my 7g i4, I had the afc wired to the crank sensor it worked fine for me, i guess to much electrical noise with the v6. Â*

If you cant find what pin on the ecu you could just tap the tach signal at the coilpacks in the engine bay.

May I ask how you know the signal isnt clean? Â*Whats your afc doing that makes you think this?</div>

It is almost an absolute guarantee on the V6 that the S-AFC will read the signals wrong because it's too noisey, though some V6 owners claim to have lucked out and everything works fine. The 4 bangers for some reason don't have this problem. Most of us realize the signal isn't clean because of the S-AFC itself show the RPM readings jump like crazy. That's what the various fixes out there are for, to somehow clean up that signal.

[JiP]

I wonder if adding some ground straps would clean up the electrical noise. It would defintly help a bit.

[Fishboy55]

<div class='quotetop'>QUOTE(JiP)</div><div class='quotemain'>I wonder if adding some ground straps would clean up the electrical noise. Â*It would defintly help a bit.</div>
Nice thought, but no. I've got a full earthground kit on my car. Problem is that the V6's crank sensor signal is about 10% noise. In other words it's a 50v pulse with a 5v noise spike. the AFC triggers at about 2v. so that means it sees the noise as an additional trigger. There are two ways to fix this. One is a transistor circuit to actually bleed off the noise and filter the signal. The other is a potentiometer on the line from the ECU to the AFC. Neither worked for me. It works for most but a few of us just seem to have noisy ECU's. But thanks for the suggestion. It's a good one.

Edit: No longer a problem. The AFC is off, soon to be replaced by an APEXI Ignition Timing Controller. Then back to the dyno....mmmm Track season is a 'comin.

Chip

[VegasMatt]

<div class='quotetop'>QUOTE(Fishboy55)</div><div class='quotemain'> Then back to the dyno....mmmm Track season is a 'comin.

Chip</div>


I hear ya there, two more weeks until our first "midnight mayhem" gotta get those last minute tuning bugs done.

[g96nt]

what happens?

your tach signal is going To be jumpy... I'd never expect it to be As smooth As your factory tach.

mine varies ~20rpm at Any speed...

is this a SEVERE deviance?

or Are you guys just being anal?

also.. you could alwaystry taking The signal from other places (right From the Sensor/Between ECU and tach....)

[Auto-9]

<div class='quotetop'>QUOTE(g96nt)</div><div class='quotemain'>what happens?

your tach signal is going To be jumpy... I'd never expect it to be As smooth As your factory tach.

mine varies ~20rpm at Any speed...

is this a SEVERE deviance?

or Are you guys just being anal?

also.. you could alwaystry taking The signal from other places (right From the Sensor/Between ECU and tach....)</div>

We're not talking about 20 rpms, we're talking more like 500 rpm jumps. There's no reason to complain about only a few rpm deviances, trust me this is a big enough issue that the Club 3G guys were all interested in fixing. They're pretty much tapped all the sources they could find for a good signal, there's no solution other than to clean up the signal.

[JiP]

Cleaning the signal could be as simple as addng a capacitor and resistor in the right place, or using shielded cable. Hell a large audio cap wired between + and - of the battery terminals might do the trick..

I duno if anyones done some electronics work on the engine and used a logic probe, but if you bring the probe anywhere near the engine you start to get low level pulses showing up, which obviously are just electrical noise being radiated by the engine block itself. Minimal with the i4, makes sense that it would be worse with a larger engine. I dont remember much about filters though. For us i4 runners groundstraps take out most of the electrical noise.

[Auto-9]

<div class='quotetop'>QUOTE(JiP)</div><div class='quotemain'>Cleaning the signal could be as simple as addng a capacitor and resistor in the right place, or using shielded cable. Â*Hell a large audio cap wired between + and - of the battery terminals might do the trick..</div>

And that's exactly what the fixes are doing.

[g96nt]

coils have the Ability to remove a fair Amount of noise from electrical signals...
more so than a resistor would... And there's no signal loss.....

[JiP]

<div class='quotetop'>QUOTE(g96nt)</div><div class='quotemain'>coils have the Ability to remove a fair Amount of noise from electrical signals...
more so than a resistor would... And there's no signal loss.....</div>

still will need a cap to level out the signal. The cap will do more for electrical noise then a coil will, not to mention coils are fairly sensitive in the frequency range they will operate in, wrong coil will do nothing at all.

[galant20022002]

are you guz looking for a tech wire for rpm gauge if so i have the software that will tell where the tech wire is and color for any car and year.on my 2002 galant v6 is a white wire at the instrument cluster that i used for remote starter and fuel enjection controller for my turbo kit.hope that was some help