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Have you considered using a PWM idle valve for some extra air during warmup? It sounds like you are using the L-jet harness so you could probably reconfigure the AAV wires or maybe a couple of the AFM wires to accomplish this.

I just recently got my GTV6 running with MSII. Right now I am using the AAV but it kind of sucks since mine doesn't open very much. I have it set up like a fast idle valve (with a relay) but with the fast idle temperature set really high so the AAV gets 12v all the time.

Eventually I will modify the MSII and try a Bosch (VW) 2 wire PWM idle valve.
What is a PWM valve, where do you get one and how do you wire it up?
 

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Will it work with an L-jet system?
 

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The solenoid valve would replace the AAV.
 

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Can you post a pic of one? Will it work using the original wires?
 

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I am thinking of using one of these things:

I guess it is VDO not Bosch. Quite a few Audi's and VW's from the 80's and early 90's came with them. They are kind of expensive new but are easy to find at the junkyard and are pretty robust if you clean them once in a while.

There is a section in the Megamanual about how to configure your MS2 for a PWM idle valve. It is below all of the stepper motor stuff.MegaSquirt-II Idle Air Control
 

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Hi-
The L-Jet system will work with a solenoid type IAC, not a PWM one. A PWM one requires a pulse width modulated output like certain versions of megasquirt can supply. A stepper type IAC requires a sequential type of output to "dial" the IAC open or closed. Certain versions of megasquirt can control those also. The stock Bosch device has a bimetallic type mechanism, not really a "solenoid." I am not sure how fast it opens and closes, either.
 

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Hi-
The L-Jet system will work with a solenoid type IAC, not a PWM one. A PWM one requires a pulse width modulated output like certain versions of megasquirt can supply. A stepper type IAC requires a sequential type of output to "dial" the IAC open or closed. Certain versions of megasquirt can control those also. The stock Bosch device has a bimetallic type mechanism, not really a "solenoid." I am not sure how fast it opens and closes, either.
Thanks. Would the solenoid work better than the stock one do you think? What cars could I get one from and what do they look like?
 

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Hey Kevin, I made use of a 45 degree silicone bend, and an alu intake pipe that I bought at a tuner shop. You can then choose whether you want to fit a cone type filter (OOOH THAT SOUND!) or modify your airbox (what I did) to accept your alu intake pipe via a silicone coupler. This way everything looks pretty stock.
 

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WRT the aux air device, I am really not sure which type would be better, but if you are sticking with the L-Jet system, I would consider making sure that the stock one is actually working before moving on to another type of unit. I have found that even though they are touted as being fairly bulletproof, about half of the ones I tested were no good. Maybe cleaning would help them, not sure.
 

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Modified AAV

I have modified an AAV and now my cold idle is pretty good. There is a little adjustment screw that can move in a slotted hole and is retained by 7mm nut. I extended the slot to increase the range of adjustment by drilling a 9/64" hole and joining it to the existing slot with a small burr and a Dremel. Now the air valve is open more when it is cold. I had to adjust the throttle stop to bring the hot idle speed back to 1000 rpm and I tested it this morning. It started and idled at exactly 1000 rpm.:smile2:
 

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Hi-
I use high impedance injectors-so usually select them with an eye to around 30lb/hr flow.
Thanks!
Al
purchased a 3.0 from a 164.i intend to put it in my 82' gtv6 2.5.i want cop,map,altitude sensor,and other details which the jetronic lacks.of course the 3.0 was motronic so i have a point for a crank sensor on the pulley.i must say with all the different megasquirt items available it gets confusing to keep a straight head.you say your setup uses high impedance injectors.i'm still trying to wrap my mind around the pros and cons of high vis a vis low impedance injectors.new low impedeance injectors are very very reasonable.map sensors are very reasonable as well.
 

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Hi,
My main reason for high vs low impedance injectors is current handling, eliminating the need for flyback circuitry or ballast resistors. I do not think there is a huge cost or performance difference. I have found suitable modern injectors of many different resistances and flow rates are readily available at reasonable cost. I try to pick ones from car models that are very numerous.
Yes, there are multiple appropriate MAP sensors, from junkyard specials to brand new. It is pretty cool to have so many choices, no proprietary/unobtanium stuff.
But that is one of the great things about Megasquirt: you can do it your way, and it will likely work great.
 

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MS ignition implemented today

The Megasquirt FI has been running well for a few months with Richards cams. So I have moved on to MS ignition control.

Al supplied me with an interface harness that requires only one wire change in the existing wiring - I had toidentify which of the 3 white wires to the coil was going to pin 1 of the Bosch computer connector. I cut it and crimped male & female spade connectors to the free ends.

Installation involved disconnecting the Bosch ignition computer and connecting the new harness with six spade terminals. A 3 wire bundle with a connector and a single wire with a spade connector have to go through the bulhead into the engine bay. I cut off the connector, passed the wires through with the existing harness and soldered it back into the harness.

I made a new timing mark at 125 degrees BTDC by cutting a piece of paper to the corresponding distance on the circumference of the pulley, attaching it with paper glue then making a yellow paint mark to contrast it with my white TDC mark.

I set the trigger angle to 125 in MS making use of the LED Dongle that Al included and the engine fired up at the first try. The timing was very advanced and I twisted the dizzy and played with the trigger angle until the advance displayed on the lap top was the same as measured with the timing light. When the engine was warmed up I drove it out onto the street and went 50 yards before it quit. One of the nice features of Al's harness is that the ignition can be switched back to Bosch control in about 1 minute. I reset the dizzy to the marks that I made before I adjusted it and drove back to the house. The problem was a short where a wire was soldered to the circuit board and one in my splice in the harness.

Now it drives OK and I can play with the ignition timing map on the fly.

I've attached some pics of the installation. I'm sure that I have left out some detail so ask for it!
 

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Thanks for the nice write-up Ed! I am working on making the connector that replaces the ignition ECU more user-friendly!
 

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Have you considered using the 60-2 trigger ring mounted to the back of the crank pulley? A lot of the front covers have the mounts for the Alfa crank trigger used on the 164. Or the bosses are cast in but not fully drilled.

You could crank trigger the spark then keep the distributor to distribute the secondary.

That's the route I am going with the LeMons car.

Maybe it is me but it seems that when I set my total ignition advance with a timing light at a reasonably high RPM, the spark seems to be a bit scattered. I think the harmonics in the belt due to the spikey load the cams put on it leads to some timing error. Big cams and stronger springs might be contributing to this.

Greg
 

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Definitely, I am working on an EDIS setup as part of my next gen motor. I have seen the same phenomenon you describe, and I agree that it is likely due to the belt drive. This setup is all part of the "minimal modification" package.
 

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Is the spark scatter on the V6 worse than on the I4? The oil pump is a likely source on Nord motors.
 
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