I'm going to be slightly brief with this because I can't wait to go drive around some more! I finally got it working *perfectly*!

Set up the board and software for the standard 420a setup:
http://megasquirt.sourceforge.net/extra/setup-neon.html

Board Mods
- Replace R12 with a 1K (1/4 watt) resistor (DEPENDANT ON STANDALONE SETUP)
- Remove Jumper from OptoOut - Tsel
- Build VR Circuit, If not Already Done (A filtering idea that came from Corbin)
- Jumper OptoOut - VrIn
- Jumper VrOutInv - Tsel
- Adjust hysteresis pot (R52 near middle of board) all the way to 0 (turn counter-clockwise till clicks)
- Adjust crossover pot (R56 at bottom of board) all the way 0 same way as above
- Turn R56 clockwise 7 turns (more on how to tune these later on)

- Build the tach output circuit (to drive your stock indash tachometer)

External Wiring Setup
- Setup a relay to power the MegaSquirt when ign. on and cranking (make sure it's fused) using the ignition switch signal at the ECU, and also send the +12v from this relay to the ASD circuit as well (flat pin at ASD relay), and scratch the ASD relay. Your relay/wiring to the ASD circuit MUST be able to support 30 amps!!!

This wire powers the coil, injectors, and alternator generator field.

- The wires I ran to the crank sensor is a shielded pair. Availible at Lowes/Home Depot as intercom/security wire on the rails they have. I ran the crank sensor signal on one wire, 5v+ from the MS on another, then the sensor ground on the shield (I know there are even better ways to do this, but I believe this is the most practical). I used the same 5v+ that powers the opto circuit to send to one of the unused wire input/outputs on the v3 board.

- I setup my own relay for my walbro fuel pump to get power directly from the battery. The MS outputs a ground signal to this relay. I highly recommend reading the fuel pump setup in the MS manual and noting the importance of putting a inertia cut off switch on it, in case the worse happens.

- Send the tach output from the MS to your tach wire under the dash.

- IAC control includes blocking off the IAC housing or filling the IAC motor with JB weld. Adding an adjustable throttle stop. Then you can add a fast idle valve with vacuum lines the MSnS can control. I currently am just using the throttle stop, then again, it's really warm where I live.

- To COMPLETELY remove the ECU you'll need to install a voltage regulator on the field wire to the alternator. I can post a diagram (from the FSM) on how to do this if you're actually intrested in it.

- Run your power/grounds to your sensors that need it if not providing from the stock ECU.

Tuning the MS Pots
- To tune the crossover point (R56) disconnect your fuse on your ASD supply wire. Crank the car, turn the pot 1 revolution clockwise till the crank RPM dissappears, then note how many it was in that direction. Then do the same in the other direction, then put it in the middle.

- Leave the hysteresis pot at zero to 1/4 turn for the most stable signal. If you happen to get any noise crank this clockwise until it vanishes (too much and your signal will dissappear completely).

If you have questions and have already done your homework, ask.

Joel Baldridge, ASE Certified Master Technician, Audi Certified Expert Technician

Ok, there is ONE more thing...

Apparently a voltage regulator is mandatory. In addition to the +12v needed to go to the alternator when you turn the car on. The ECU does not seem to trigger it's switch until the car is running (which it never sees as running with no crank input).

I drove around for near an hour until my deep cycle battery died. It was kinda funny too, I noticed my Zeitronix Wideband LCD start to fade out, and had been hearing this funny beeping from my power inverter for my laptop. I looked at the voltage in MegaTune and my car was running on 6-8 volts for a several seconds before it died.

Joel Baldridge, ASE Certified Master Technician, Audi Certified Expert Technician

And the Solution...

Look at Page 15
http://www.electromotive.us/pdf_files/neon99.pdf

It tells you the part number for the external voltage regulator, and how to wire it up. Expect to pay $15 for this regulator at AutoZone.

Update:
The Borg Warner Select Series one is $30 from O'Reilly's (I'm a professional mechanic that doesn't touch any of the crap AutoZone sells). 18 AWG (pink) Female Bullet Crimp on Terminals fit the regulator perfect.

Joel Baldridge, ASE Certified Master Technician, Audi Certified Expert Technician

Sweet...good to hear you got it working Wicked.
I read it once..but too much information, and I am too stressed right now to take in more info... I will read it later on.
But good that you got it working! I can imagine how you feel when you see that ROCK SOLID RPM.

I do have many questions.
But I don't have the time now to ask.
But let me ask this quick.

Do I have to do EVERYTHING you stated inorder to get solid RPM?
Because I don't want to do rewiring in my car.
Will just doing the mod of my Megasquirt. the OPTO and the VR will do the trick?

Do I HAVE to make my care COMPLTELY STAND ALONE? like totally remove stock ECU, remove CPS from ECU (then no more iAC, and so on?)

Thanks.

~~~~~~~~Modification~~~~~~~~
Performance: MegaSquirt v3.0 Fuel & Spark, 8.6:1 JE piston, Eagle Long Rods, SPEC III Clutch, EVOIII B16G, FMIC, Aeromotive 1:1 FPR, Walbro 255HP, 680cc Injectors, 2.5" DP, 3" Magnaflow Cat, 3.5" Greddy EVO CatBack, Greddy Electronic EGT,FUEL,BOOST,A/F gauges...
Interior: Racing Seats, Metallic Interior, 15-Speakers System, Keyless, Dynomat Insulated, Neons...
Exterior: 1999 Body with turbo wing, Halo Projector Headlight, 4300K HID, 17" Mille Rims, GSX Calipers...
Coming Soon: Water Injection, Redo Undercarriage, Repaint Exterior


$240 For New Complete GSX Calipers Kit (Calipers, Bracket, Shim, Pad, Bolts, etc) Email Me If Interested!

1995 RED Eclipse GS-'T': Stage VI 20PSI
2010 Audi S5 Quattro

Gilee, there are several side effects to the stock ecu not getting a tach signal (which I covered how to deal with each one), so you may wish to try leaving it connected to the stock ecu like corbin's setup, and trying his method.

I can confirm the spikes I was getting was not caused by the alternator, not the stock wiring, as I drove around with the alternator field generator off and the sensor wired just to the MS, and was still getting the spikes with the default 420a MSnS setup.

Using just the opto circuit on the v3 board is the problem. It may be the 5v power to the opto circuit isn't stable enough, or the tiny capacitor in the circuit which makes the optoisolator WAAAY to sensitive.

The VR circuit is the way to go, but you must run it like I did if you don't want the stock ecu hooked up at all.

Joel Baldridge, ASE Certified Master Technician, Audi Certified Expert Technician

Yes, I understand what you saying Wicked, and but I am really tight in time right now. work, college, and just going to a trip.
So I really want to try to see if a shorter method will work. I just want to eliminate the RPM SPIKE for now. so if only need to mod the megasquirt unit itself, then I can do it in an hr. but if I need to rewire the car, and do this and that, then, it will take me alot more time!

So what I basically want to try is, can I try a portion of your mod?

Like just performa the MS unit mod. (OptoOut -> VrIn -> VrOutInv -> Tsel) But leave the car side of the mod. (wiring, fully standalone, etc). So I just have the CPS fully connected to the stock ECU. Just tap the signal cable to the MS. and so this way, I can have my Stock ECU control the IAC.

The only REASON I don't want to go full Standalone yet, is because of the IAC (idling issue) and the amount of time I have now.
I will try to find a way to get that working without stock ECU later on. (maybe after Xmas) but for now, I want to keep my stock ECU.

So from your experience.
Do you think on what I want to do will eliminate the RPM SPIKE? or you know as a fact (or tried) that the RPM spike will still be there?
Like I just change OptoOut -> VrIn -> VrOutInv -> Tsel, and tune the two pots. Will just doing this will eliminate the RPM SPIKE?

Thanks!

~~~~~~~~Modification~~~~~~~~
Performance: MegaSquirt v3.0 Fuel & Spark, 8.6:1 JE piston, Eagle Long Rods, SPEC III Clutch, EVOIII B16G, FMIC, Aeromotive 1:1 FPR, Walbro 255HP, 680cc Injectors, 2.5" DP, 3" Magnaflow Cat, 3.5" Greddy EVO CatBack, Greddy Electronic EGT,FUEL,BOOST,A/F gauges...
Interior: Racing Seats, Metallic Interior, 15-Speakers System, Keyless, Dynomat Insulated, Neons...
Exterior: 1999 Body with turbo wing, Halo Projector Headlight, 4300K HID, 17" Mille Rims, GSX Calipers...
Coming Soon: Water Injection, Redo Undercarriage, Repaint Exterior


$240 For New Complete GSX Calipers Kit (Calipers, Bracket, Shim, Pad, Bolts, etc) Email Me If Interested!

1995 RED Eclipse GS-'T': Stage VI 20PSI
2010 Audi S5 Quattro

I would try doing just what you said. I believe it will eliminate the spikes. It's almost just how corbin did his, only it goes through the opto circuit to possibly make the signal more stable.

Joel Baldridge, ASE Certified Master Technician, Audi Certified Expert Technician

OK... I will try just that. hopefully I will have the time to give it a shot soon.

I let you guys posted!
Gil

~~~~~~~~Modification~~~~~~~~
Performance: MegaSquirt v3.0 Fuel & Spark, 8.6:1 JE piston, Eagle Long Rods, SPEC III Clutch, EVOIII B16G, FMIC, Aeromotive 1:1 FPR, Walbro 255HP, 680cc Injectors, 2.5" DP, 3" Magnaflow Cat, 3.5" Greddy EVO CatBack, Greddy Electronic EGT,FUEL,BOOST,A/F gauges...
Interior: Racing Seats, Metallic Interior, 15-Speakers System, Keyless, Dynomat Insulated, Neons...
Exterior: 1999 Body with turbo wing, Halo Projector Headlight, 4300K HID, 17" Mille Rims, GSX Calipers...
Coming Soon: Water Injection, Redo Undercarriage, Repaint Exterior


$240 For New Complete GSX Calipers Kit (Calipers, Bracket, Shim, Pad, Bolts, etc) Email Me If Interested!

1995 RED Eclipse GS-'T': Stage VI 20PSI
2010 Audi S5 Quattro

This Post Should get pin to the top forever! LOL. I am excited!

Anyhow, I tried on what Wicked said above, and it completely eliminated the RPM SPIKE. You don't have to do all the steps stated above to just eliminate RPM spike, and the simpliest way that will eliminate the RPM SPIKE is doing the following v3.0 board mod when you try to read the RPM signal off from the CPS.

Just tap the signal from the blue/white wire from the CPS to the MS while all 3 wires are still connected to the stock ECU, shielding that tapped wire to the CPS might be a good idea. Then doing the following mod will be good to go with no RPM SPIKE!

Thanks to Wicked's and Corbin's hard work, so I just make it a simple and step by step instructions below! Enjoy guys!

Board Mod specifically for v3.0 Megasquirt board.
. Build both the Hall/Optio & VR input circuit sections
. Jumper TACHSELECT to XG1
. Jumper D1
. Jumper D2
. Jumper OptoIn to +5v on proto area
. Jumper OptoOut to VrIn
. Jumper VrOutInv to Tsel
. Replace R12 with a 1.3k to 2k resistor
. Remove C30
. Adjust hysteresis pot (R52 near middle of board) all the way to 0 (turn counter-clockwise till clicks)
. Adjust crossover pot (R56 at bottom of board) all the way 0 same way as above
. Turn R56 clockwise 7 turns

Tuning the MS Pots
- To tune the crossover point (R52) disconnect your fuse on your ASD supply wire. Crank the car, turn the pot 1 revolution clockwise untill the crank RPM dissappears (0 RPM), then note how many turns was made in that direction. Then go back to exactly 7 turns position and do the same in the other direction, then put it in the middle of the two turns. (For my setup, 7 turns is the sweet spot)
- Leave the hysteresis pot at zero to 1/4 turn for the most stable signal. If you happen to get any noise crank this clockwise until it vanishes (too much and your signal will dissappear completely). (For my setup, zero is the sweet spot)

~~~~~~~~Modification~~~~~~~~
Performance: MegaSquirt v3.0 Fuel & Spark, 8.6:1 JE piston, Eagle Long Rods, SPEC III Clutch, EVOIII B16G, FMIC, Aeromotive 1:1 FPR, Walbro 255HP, 680cc Injectors, 2.5" DP, 3" Magnaflow Cat, 3.5" Greddy EVO CatBack, Greddy Electronic EGT,FUEL,BOOST,A/F gauges...
Interior: Racing Seats, Metallic Interior, 15-Speakers System, Keyless, Dynomat Insulated, Neons...
Exterior: 1999 Body with turbo wing, Halo Projector Headlight, 4300K HID, 17" Mille Rims, GSX Calipers...
Coming Soon: Water Injection, Redo Undercarriage, Repaint Exterior


$240 For New Complete GSX Calipers Kit (Calipers, Bracket, Shim, Pad, Bolts, etc) Email Me If Interested!

1995 RED Eclipse GS-'T': Stage VI 20PSI
2010 Audi S5 Quattro

bookmarked ....

Member # 751


FOUNDER of the Central Cali chapter of 2GNT!
(I got kicked out after I refused to go Cow tiping) - Hehehe you know who this is for

If you STILL are getting spikes (or if you are getting spikes running as a piggyback). First make sure your MS case isn't bolted down to (or touching) a metal part of your car (you just created a ground loop).

The following post from the MSnS forum has helped tons of people (including me ridding of the random intermittent spikes I was getting on random sensors) by fixing a design flaw on the v3 board when used in electronically noisy environments (i.e. automobiles). Even if you have done nothing else, I've mentioned, on any v3 board setup. If you are having any kind of resets/spikes I recommend doing the following:

Joel Baldridge, ASE Certified Master Technician, Audi Certified Expert Technician