R33 RB25 with VEMS 3.3 and Adapter Harness

[irishtwincam]

So we started the wiring today.
Made good progress until it came to actually putting the RS232 pins into the econoseal plug.
45 minutes later and with only two pins insterted into the econoseal plug, it felt as though the plug wasnt fitting the ECU correctly.

Rather than risk breaking the ECU pins we called it a day.

Bob, if you can hear me, gimme a buzz dude
We could do with your help getting these pins in before we damage something.
Wiring we can do, getting the pins into the plug we can't.

[rob@vems.co.uk]

What happened with all those lovely crimped wires I gave you?

[irishtwincam]

Well the 8 earth wires from the R33 ecu needed to be soldered together, so we just used Maplin high quality black wire.
Solder one end to ECU plug, solder the other ends all together one at a time?

The RS232 needs to be long enough to reach a laptop placed on the roof of the car

We were saving the precrimped wires for sensors.
Crimped end into VEMS ECU econoseal plug, other end soldered to R33 plug.

We could have used two precrimped wires for the RS232 and extended them but it was for experience that we made the long RS232.
And to save precrimped wires for short adaptor plug functions.


Remember, the goal for stage 1 was to get all power and earths sorted and simply power vems up
so we can see megatune acknowledge that the ecu is powered, and not pop the 1amp which has yet to be fitted.
Then disconnect and actually start hooking up sensors wires.
This was your advice no?

[rob@vems.co.uk]

The wires need to be soldered together, but its best to expose them and twist together.

The RS232 needs to be short, the extension cable is the thing that allows the laptop on the roof to be connected.
Theres a short length of shielded cable in the wire pack.  Unshielded stuff will act as an antenna and draw loads of noise in

You're going the right way, but the crimps were done to make things easier, theres loads of them here if more are needed - I'm sure I put spares in the pack.



Its all good, and heading in the right way.

Rob

[irishtwincam]

Dur, I suck!

Monday you can go through what is for what with us.
Also have some wire label stickers so we cant forget :-D

I saw the short shielded wire but there were only 2 signal wires and the shield earth.
The RS232 diagram showed and earth from pin 5 so I didnt think it applied?

Again as I say, we can go through stuff toorrow if your free.

Cheers dude.

[rob@vems.co.uk]

No you don't suck, I know what I mean, sometimes explaining it means I take short cuts.
The shield should go to the earth cluster:

As should the air temp sensor ground.

[irishtwincam]

One of the outputs from this excercise was to compile a list of diagrams and info we found essential to doing the job
of making the adaptor loom.
I know there are existing diagrams for various tid bits of info but I was going to stick it in a doc for your perusal.

One such diagram would be to label each component in the package as I have obviously missed out that the RS232 was the short shielded bit. I thought thats what it might be for, but didnt think enough...

[irishtwincam]

Did coil wires, tacho and water temp today.
I picked up the crappy solder tin so it took 95 times longer than it should ahve.

Called it a day after damo helped finish it off and check my stuff.

CAS wires need to be verified, then solder up flyback, injectors and whatever else is on that pin.

If we get that done well probably call on you to do a hands on instruction of the cas disc swap.
Dam is puicking up another stock CAS unit this week so we can switch quickly between VEMS and stocku ECUu.

[rob@vems.co.uk]

Cool stuff, it takes ages to do the first one, the next time is much much quicker.

[irishtwincam]

Yeah I'm very glad of the experience.
But doing it right the first time helps build a solid mental foundation for future work.
No doubts. Dont associate stress with the task.

[irishtwincam]

All wires done except for ECCS IN, says its emant to go to 4pin/pin4?
WBO2 not hooked in so C18 is pretty bare.
Need to continuity check every single wire and confirm correct location before testing.

Heres the project car.


Fuel support mods done. Coilpack on the bokos, tubby etc.
WBO2 bung and IAT bung need fitnig, will do last.


Adaptor loom pogress.
CAS pin 52 was not present no the factory loom!



Mine versus PhatBobs demo item

[irishtwincam]

I nede to root back through the kit bag and look for an IAT plug and 4pin plug

[irishtwincam]

Everything except AAC pin and ECCS In to 4pin/pin 4 are connected.

Continuity tested everything wed wired against diagram.
Everything was 100%
Plugged it in, finalised TPS calibration.

TOP TIP: Force throttle body to closed position/throttle stop by hand at the throttle body.
Calibrate low adc. Force throttle to WOT at the throttle body, calibrate high adc.
There was a bit of slack in the cable at either end.

With the Kamimoto throttle body, the TPs is fixed in its location with no room for adjustment.
Unfortunatly that puts the clsoed voltage at 0.005v and full throttle at 3.5v
I'm sure the sensor is sigmoid so the first 15% of throttle is hard for the ecu to discern.
the top 10% is better, but still a little laggy.
Can anyone recommend a bolt on replacement 5v linear TPS?

low adc is 11
high adc is 189, i think.

Water temp was .5 degrees below air temp (reading fine as far as we were concerned).
Air pressure was 1kpa away from Cambridge airport meterological readings.
Changed MAP calib offset from 6.5 to 6 to get it aligned.

Fuel pump cuts in fine.

Next up, IAT wiring, WBO2 wiring.
Put disc into spare CAS, which has yet to be purchased.

Good afternoons work.

[irishtwincam]

Its alive!

Swung, caught sputtered and died.
Not having a vac pipe to the MAP sensor will do that!
Have cranking rpm, spark and fuel.

I need to rewire part of the adaptor harness to use the microphone cable for teh CAS triggers.
DOH!

WBO2 wiring and thats about it!

Map the biatch!

[irishtwincam]

Its starting.
Its idling.

Problems that were overcome today.

Our setup:
Individual coil controlled via stock igniter.
4 worked, 2 didnt.
Thanks to Rob it was noticed that we were 2 drivers down due to a 4cyl hardware config.
Much splicing later, the coilpacks were paired at the 36pinEC, the ignition outputs configured for those 3 pins.
The spark pattern set in the ignition outputs. Were now running wasted spark via original igniter and voila.



There was a strange intermittent rattle from the engine, that was because VVT was configured for 1200rpm, that was shifted up to 1500 and the noise went away.

The on screen timing when running didnt quite match the crank, so we adjusted for this,
partially at CAS, and more finely in the software.

The result was a crisp startup, smooth idle at ~1000rpm. Much better than what is in the video.
And the idle in the video was damn good!
You can see in the vid Rob lowering and plateauing the low rpm/throttle area in the VE tuning table.
Idle cant be lowered any mroe mechanically due to the massive TB not having any more adjustment :-(

Good earths, follow the manual, check, double check and triple check ALL wiring!

Bravo for Bobs help and documentation!