Mitsubishi Mighty Max

[ChargerX3]

Great. Made it to salt lake today for work. Dragged old red behind be on the trailer. Thursday I wrap up and head north to Idaho to register it. Hopefully all these El Niño storms let up so I can make it.

[Jeff V.]

Do you mind posting your VIN? Or at least PMing it to me? I'd like to see what ECU your truck has.

I'm guessing it's MD143195 (Cali emissions), but I'd like to check.

[ChargerX3]

I can do that. I'll pm it to you in a bit.

[Jeff V.]

No hurry. Thanks.

Does your truck have a 12 pin diag port like the 1G 3S did?

[ChargerX3]

PM sent. Yes it has the same plug just under the drivers dash. What are you looking into?

[Jeff V.]

Nothing too crazy at the moment. I was just going to see if I could find a spare ECU to play with and maybe write an EvoScan profile for it, but those don't seem to be any easier to find than the trucks themselves.

[ChargerX3]

Bingo. Had a MM guy tell me the same thing. Apparently 90 is a perculiar year for ecu's. Being Cali spec doesn't help either. Lol.

[Jeff V.]

Looks like the ECU change coincides with going to the Karman MAF in the '91 model year.

Code: Select all

ECU
6/89 - 5/90	MD143195	Cal
6/89 - 5/90	MD149410	Fed
6/90 - 5/94	MD162825	Cal
6/90 - 5/94	MD162826	Fed
6/94 - 5/95	MD162826	All

MAF
6/89 - 5/90	MD118127
6/90 - 5/95	MD151055

**EDIT: Fixed a typo in the first ECU PN**

The later MAF is the same as on the NA 3S. So if you run into ECU problems, just drop in a later Max ECU (or 91-92 SOHC Stealth) and then upgrade the MAF to the Karman type.

http://vfaq.com/mods/2GMAF-1G.html

I think the Cal SOHC Stealth ECUs were EEPROM, and the Fed ones just had the socket for it. My 94 SOHC is EEPROM, but it's got the newer style connectors rather than the older 'chunky' style early DSM ones.

Also, there are only 3 V6 engines harnesses for this truck, all corresponding to the ECU/MAF change. It's interesting that the 95 and 96 trucks are all Fed. I'd have expected the opposite.

[ChargerX3]

Just got back after driving all day. Pic from earlier.



I want to jump right into the Evo maf as the current one sucks bad. Virtually has no resolution. Would love the hear the good and bad on eeproms vs chrome. If possible I would grab a 1st gen sohc and socket it for one.

Anyways just pulled my ecu. Looks like someone beat me to it.




Look close at the charred black spot where the old cap used to be. It's probably a couple layers deep. Arg! Probably why it's doggy and idles high. Need to replace asap.

[Jeff V.]

"Rebuilt" eh?

[ChargerX3]

Yea shoot me please, or just school me on the eeprom so I can move on.

[Monochrome]

[quote=""ChargerX3""]I want to jump right into the Evo maf as the current one sucks bad. Virtually has no resolution. [/quote]

Upgrading the MAF will do nothing to improve the drivability. I don't know who started that rumor but the EVO MAF really isn't an upgrade....

[Jeff V.]

Have you seen the old ultrasonic DSM MAFs? I don't see how replacing it could not help. Especially since he'd have to do an ECU replacement to accommodate it.

When I had the flash ECU and Evo MAF in Vira's car it idled noticeably smoother and just all around felt better.

[ChargerX3]

[quote=""Monochrome""]Upgrading the MAF will do nothing to improve the drivability. I don't know who started that rumor but the EVO MAF really isn't an upgrade....[/quote]

I believe you did when you first installed one years ago. Shortly after I did the same and I noticed better idle and slightly smoother throttle response. You've been away too long to remember Mr exo.

[DCIV]

I believed it started with that canadian dr750 car when he put in an evo maf and did a write up about it.


Coop

[Monochrome]

[quote=""ChargerX3""]I believe you did when you first installed one years ago. Shortly after I did the same and I noticed better idle and slightly smoother throttle response. You've been away too long to remember Mr exo. [/quote]

That would be Aaron.

Actually I'm pretty sure it was Jeff that convinced us this MAF was the end be all and we just took that at his word.

At any rate, no a MAF swap does nothing unless there's something wrong with your current one or you have a wild imagination.

[Jeff V.]

At any rate, no a MAF swap does nothing unless there's something wrong with your current one or you have a wild imagination.

Or if your current MAF is maxed out. Which obviously isn't the case with Steve's truck, but it can still be an upgrade.

Go tell all the DSM guys that replacing the trashcan MAF with the Karman MAF isn't an upgrade. That's basically what Steve is faced with.

Anyway, based on mine and Steve's results, changing the MAF AND the ECU can definitely improve drivability. More accurate air/fuel metering and faster response time is never a bad thing.

[Monochrome]

[quote=""Jeff V.""]Or if your current MAF is maxed out. Which obviously isn't the case with Steve's truck, but it can still be an upgrade.

Go tell all the DSM guys that replacing the trashcan MAF with the Karman MAF isn't an upgrade. That's basically what Steve is faced with.

Anyway, based on mine and Steve's results, changing the MAF AND the ECU can definitely improve drivability. More accurate air/fuel metering and faster response time is never a bad thing.[/quote]

So my point about the MAF swap stands as it does nothing without the ECU which is the real upgrade.

Now that I think about it, if the MAF swap really did make a difference in Viras car, it's because you didn't change all the tables over and it just happened to be a better tune with the mix-matched MAF. Back then I recall all we did was change the MAF size and adder value when really it should have been the MAF adder and the whole scaling table. I remember figuring that out after selling my white 99.

[Monochrome]

[quote=""DCIV""]I believed it started with that canadian dr750 car when he put in an evo maf and did a write up about it.


Coop[/quote]

Yeah I think that's where it began too. Then Ray confirmed it a few times later on.

The stock 3/S MAF loses count around 450whp and that's about the time the EVO MAF starts to show a restriction.

[DCIV]

[quote=""Monochrome""]Yeah I think that's where it began too. Then Ray confirmed it a few times later on.

The stock 3/S MAF loses count around 450whp and that's about the time the EVO MAF starts to show a restriction.[/quote]

he was the first person making power from dr750 and i swear at the time people would have sucked his dick if it would have given them some of the power.


Coop