BAWC Forums

Woah - nice!

[quote=""Jeff V.""]Some of them may use the correct pins with a different housing. Before you cut too much, see if you can back the pins out. There's usually a either plastic locking tang you can lift up, or a metal tang on the pin that you can push down on.

Find an old windshield wiper and remove the metal reinforcing strip from inside it. Grind it down to fit inside the connector and then stick the other end in a wine cork. Makes for a great connector disassembly tool [/quote]

Yea. I wasn't going ape shit on it. Lol. That's a good idea with the wiper. I've used the hairpin trick for the ecu pins. That one seems to work very well. I'm going to try and even use all the Mitsubishi wiring I can from my donor harnesses so that I keep similar gauge and conductivity across all circuits. Now that I think of it I think I pulled another v6 max harness too. Can mix match those as well.

That was the secondary reason I wanted my parts truck, after the transmission. To get the harness. I was hoping to build the custom Sport/Max harness while still keeping the truck drivable.

Yea, the second harness is a huge bonus. Im pretty sure I splice in my MAF pigtail from the other max harness.

Found this on Club3G. Might be useful.

I'm going to run the Mivec solenoid with the OE ECU. I was concerned that I may damage the ECU because the current draw of the Mivec solenoid is higher than that of a smaller solenoid. I current tested the EGR, Evap, and VICS solenoid and found that they draw 0.4 amps each. The Mivec solenoid draws about 1.7 amps unloaded, meaning with no oil pressure to fight against.

I'm going to disassemble the 2006 Eclipse ECU I have and see if I can ID the physical circuit that controls the MIVEC and spec out the parts on the board. With a lot of luck, we can replace some of the surface mount parts on a 98-00 ECU and re-purpose an Evap solenoid circuit or something. We might even be able to add the parts to an unused boost solenoid circuit on an NA ECU.

I guess we'd need two circuits since you have two solenoids though.

That is some good info. I remember reading somewhere that they drew quite a load. If we could make this work on the OEM board that would be great. Otherwise I was thinking of running the EGR circuit to a relay, but that would be a last attempt. Especially since the delay from ECU to final actuation at the solenoid would be significant.

A relay can't cycle fast enough for the PWM. Remember, it's not an on-off switch. It fires the solenoid for 2 seconds at 12V to engage it, then pulses it at ~400hz to keep it open. It's more like a fuel injector in that regard.

My biggest concern is that the traces on the circuit board won't be beefy enough to handle the load. Worst case we can design some kind of external driver module like some other people did, but that's going to require some serious effort.

Oh, must have not shared this with you. I got in contact with one of the 3G guys who was figuring out the PWM parameters on the solenoid last year. He finally gave up on the project because he found that he could run the solenoid for over a minute and not have it raise temperature...at all.

His advise to me was "when are you ever going to run full open throttle for over a minute"? I wanted to disagree, but I really couldn't think of too many instances where I would be running over 4k rpm for that long.

I'm still all for going the ECU route if its plausible.

I do think you mentioned that at some point. It's tough to keep track of what I heard and where I heard it from.

Either way, it still has to be a circuit capable of handing the high current. I'd prefer to do it the 'right' way, but if we can't, oh well.

Even if its going to trigger a relay? I thought we could get by with a lot less that way?

True. At that point we should be able to use pretty much any switched output. I think some of the solenoids are still PWM, but we can always set them to 100% output.

I didn't know they were PWM?

At least on the 94-96 ECU, the boost solenoid, EGR solenoid, and boost gauge output are controlled by the on-chip PWM modules. I'd have to find my notes for the 98-00, but it should be very similar. The fuel injectors are done with a sort of software emulated PWM. Those use on-chip timer functions. The differences are really academic, especially since we're not going to be re-purposing any injector circuits.

But using the boost solenoid and boost gauge could be our ticket. I had for gotten all about the gauge being ECU controlled.

Oh, good point. So run Boost Solenoid for one Mivec Solnoid, and the Gauge for the other solenoid? Man i really hope that works.

I'll dig into it more when I get back. Do you still have a broken solenoid? If the terminals aren't completely sheared off, it'd make for a good bench test part.

I have a couple now. I picked up a few 4cyl ones. They look identical except for the mounting arm.

Time for an update:

https://www.youtube.com/watch?v=c38bKWK ... JMWylbOUQQ

Hmmmmm. Didn't seem like it wanted to stay running.


Coop

Seeing as we don't yet have a 3.8L ROM for that ECU, this isn't surprising.

The fact that it ran at all is a big first step. It means the ECU is successfully triggering the ignition transistor....which means his wiring is correct.

Ahhh. I just figured the rom stuff was all sorted out with all the ecu dumps you've done. In any case it's a great job. Can't wait to see what you think of it when you are done.


Coop