Basil Daham, 1995 VW Golf VR6

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jassem99
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Basil Daham, 1995 VW Golf VR6

Post by jassem99 »

Name: Basil Daham
Vehicle: 1995 VW Golf VR6
Engine: 2792cc, AAA engine code, 12 valve, free-flow filter & exhaust, T3/T4 turbo, front mount intercooler, spacer to lower CR to 8.5
Injection: Port injection, 440cc/min Delphi HighZ injectors, Motronic ECU, 60-2 trigger wheel, variable reluctance crank sensor, PWM 2-wire bosch idle valve, Bosch coolant and intake temp sensors, coilpack with integrated module driving 3 coils in wastespark mode
Description: The objective of this install was to use the original wiring loom. To do this, an old 68 pin ECU was cannibalised and turned into an adapter. The MS was installed inside the car, with wires running to the 'ECU' box. All the original sensors and actuators were used. Shielded wires were used for the VR sensor.

MS v3 internal mods included using the LED's to drive the VAG ignition module (+5V to trigger coil), with a 330ohm resistor placed inline to limit current drawn from CPU. A TIP122 was installed to PWM control the 4 ohm idle stability valve. Bias resistors were replaced with 2.2k 1% ones to suit Bosch sensors.

To make the install compatible with the VAG relays, the following was done:

1. The ISV was fed +12V by jumpering a wire from T68/23 over to T68/27 through a 10A fuse to provide power to the idle valve.
2. A relay was used to ground T68/9 when ignition was switched on. Grounding T68/9 allows the ECU relay to come on and feed the injectors, ISV and megasquirt through T68/23.
3. Attempts were made to ground T68/28 in order to enable the O2 sensor relay, but these were not successful and the O2 sensor heater was abandoned early on. Any suggestions on getting the O2 sensor heater to work would be helpful in future.

Pin configuration:

MS GROUNDS (8,9,10,11) go to T68/1, T68/7, T68/55, T68/56, T68/58
MS SENSOR GROUND (19) goes to T68/33
MS MAT (20) goes to T68/36
MS CLT (21) goes to T68/14
MS TPS SIGNAL (22) goes to T68/40
MS O2 SENSOR SIGNAL (23) goes to T68/20
MS TACH IN aka VR+ (24) goes to T68/67
MS VR- (7) goes to T68/68
MS TPS Vref (26) goes to T68/41
MS coil A (36) goes to T68/8
MS coil B (25) goes to T68/52
MS coil B (27) goes to T68/60
MS +12V (28 ) goes to T68/23 through 5A fuse
MS FIDLE (30) goes to T68/53
MS INJ1 (32,33) goes to T68/2, T68/4 and T68/25
MS INJ2 (34,35) goes to T68/3, T68/24 and T68/26
MS FUEL PUMP (37) goes to T68/6

Options included:

MS LAUNCH CONTROL on DB37-pin 3
MS Shift light CPU10 on DB37-pin 4
MS Shift light CPU11 on DB37-pin 5
MS BOOST control on DB37-pin 6 routed through T68/31 (hence to charcoal canister)
MS Tacho out DB37-pin 29 was fed to T68/22 to drive cluster
MS SWITCHABLE MAPS on DB37-pin 31

Crank signal was decoded using MSnS-E 029q2. 60-2 wheel, with 14th (15th if 0 and 1 are the missing teeth) tooth at TDC. Trigger angle 60*. Trigger position A was 5, Trig pos B 25, Trig pos C 45, Trig return pos A 14, Trig return pos B 34, Trig return pos C 54. Spark output was INVERTED since the VW module goes from 0 to 5V when it wants to trigger the coil. Using 3ms on the MS for now.

Will post VEX/MSQ's when car is properly tuned.
majic
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Joined: Wed Nov 02, 2005 6:10 am

Post by majic »

Dude... awesome write-up. I'm working on a MKIV right now... I'm trying to leave the stock ECU in there, for purposes of keeping the stock dash. But I also hope to use something like the DigiDash project.

Good work!
Paul_VR6
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Posts: 61
Joined: Thu May 27, 2004 10:14 am
Location: Elkton, MD

Post by Paul_VR6 »

Love the harness idea, I just got a car running on one today, much like yours. I just tied the wire for the heated O2 relay to the fuel pump pin and it seems to be working great. I still have to wire in the relay to ground the wire for the ECM relay. I'm not quite sure how it works stock, as none of the transistors in the stock ECU ohm out to Pin9 at all.
-Paul
1995 GTI VR6 12.833@105
2.8l 12v on MS1-3.57/HR10G - retired
3.2l 24v on MS3 - beta test completed - retired
??? on MS3/3x/IOx/? next up...K&P Performance - KPTuned.com
redeye
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Post by redeye »

did you get your car tuned ? i will be going down this road soon and im about 20 mins drive from you feel free to call down and help me out :) :)
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