Suzuki Swift T3 conversion - engine no start

[fixkick]

on our cars the tacho runs of the (coil minus , but reduced voltage via the suppressor)
the only question is where is it.
answer my guess inside your ignitor, thus the extra pins.

[fixkick]

more
here is a drawing I made that shows where and how the ECU monitors the ignitor , supressor brown tacho wire.

[fixkick]

note how on this car
the dashtacho meter shorting (bad) to ground , kills fuel. dead.
so does, cruise box.
and TCM box.
any thing that kills A1, fueling ends now.
there are many spark systems used, some ive no clue, like COP spark engines, with 6 coil spark coils. how does the monitor work there.?

[fixkick]

your fsm states IGF
is dead

page 6C-34
IGT is ignitor gate drive.
IGF line is ECU read back, (called the spark monitor)

IGT is the ECU driving dwell and spark,
if IGT toggles and the monitor pin does not
that means the coil is open(ohm it yet)
or the ignitor is dead
if the IGT line is dead, the ECU is bad or CMP /CKP dead. (we are not getting DTC codes for CMP or CKP so they are not dead) this is why cranking for 5 full seconds is so important,

[t3tom]

your fsm states IGF
is dead

page 6C-34
IGT is ignitor gate drive.
IGF line is ECU read back, (called the spark monitor)

IGT is the ECU driving dwell and spark,
if IGT toggles and the monitor pin does not
that means the coil is open(ohm it yet)
or the ignitor is dead
if the IGT line is dead, the ECU is bad or CMP /CKP dead. (we are not getting DTC codes for CMP or CKP so they are not dead) this is why cranking for 5 full seconds is so important,

The Ignition coil was tested:
primary = 1.4 ohms
secondary = 13.46K ohms

- Below is a picture of igniter and noise suppressor from another Turbo Sprint car which has a running engine. We will double check that the Igniter chassis has a good ground, on the non running car later today. I wonder if a poor igniter ground can also cause code 41?


- Also attempted to sketch schematic showing igniter and noise suppressor guts. Guessing a bit on the igniter internals, as I was using bits of information posted on various Suzuki forums.



corrected image below on july 11 2016 to reflect errors in orange and yellow wire colors as well as expected voltage values while engine is running

[fixkick]

oh boy the ignitor uses chassis ground, thats bad.


pin 1 is a 5v 0v square wave, but fast, it goes low for short dwell time. 10/1000 of a second
then the coil fires,
the cap there pin 3 is another noise suppressor.
the base goes to pin 1 , via a not shown resistor.
the pin 2 goes to pin 4 , via a voltage divider, network. and has a complex pulse out. (its the minus coil signal, reduced)
the noise suppressor is only for you r tachometer.. that way it cant kill spark if tach shorts, suzuki learns.....

with a scope we check pin 2 first if dead, we check pin 1. if dead, the ecu has problems, if its ok pin 1, then ignitor is bad.

but your ignitor ground is missing!
bingo
make a ground wire with lugs and find the best ECU ground in system and connect it.

thanks for sharing, fun to see the turbo version !!!

[fixkick]

most cars like this have this bundle of grounds on the distributor base., that be best spot. as that is ECU main ground.

[t3tom]

Thank you for the circuit explanations, and great advice to add a better ground wire to the igniter. Hopefully the engine can be started soon!

[t3tom]

Updates on efforts to start my friend's T3 Sprint.
Installed my new battery in his car during testing to rule out low voltage.
Checked orange and yellow ignition trigger and fail feedback wires for continuity.
Checked coil brown/white and black/white coil to igniter wires for continuity and voltage for blk/white.
Checked distributor rotor and base timing at cylinder 1 TDC.
Did crank test check for voltage at igniter pins.

Friend's non running car: Igniter / Coil wire test results:
Black/White: 12V (+BAT Ignition on)
Brown/White: 12V (Coil - Ignition On)
Brown/White: 10V (Coil - Starter cranking)
Ground Connection: 0 ohms
Orange: 0.2 to 0.4V (Igniter Trigger signal from ECU while cranking)
Yellow: 5.2V (Igniter Feedback Fail signal to ECU while cranking)

We forgot to check if code 41 was still there after all this.
His engine still has no sign of wanting to start however.

Then, I took his currently installed ignition parts and spares home to my own running T3. I installed and tested his parts. The
results were the same regardless of my parts or my friend's parts used:

Testing involved 3 igniters, a T3 coil, spare G13A coil, 1991 T3 ECU, 1989 T3 ECU, all tested one at a time on my running T3 - resulted in normal engine start up in my car with a normal code 12 in Diagnostic mode.

T3tom's running T3 as a reference case:
Igniter / Coil wire test results:
Black/White: 12V (+BAT Ignition on)
Brown/White: 12V (Coil - Ignition On)
Brown/White: 10.5V (Coil - Starter cranking)
Ground Connection: 0 ohms
Orange: 0.1 to 0.7V (Igniter Trigger signal from ECU while cranking)
Yellow: 0.0V (Igniter Feedback Fail signal to ECU while cranking)
Orange: 0.7 V (Igniter Trigger signal from ECU while running)
Yellow: 1.0V (Igniter Feedback Fail signal to ECU while running)

Note: The voltage measures above from my reference car while the engine was running were obtained using a multi-meter. Ideally I should have used an oscilloscope to see what the waveform looked like. Guessing the signal voltage actually varied between 0-2 Volts.

My friend wants to replace the whole harness and start over but probably something simple was overlooked. Something in his yellow ignition fail feedback signal wire looks suspect. Do you have some other ideas? We may need to consider getting an oscilloscope for more tests if further wire by wire checking reveals nothing.

additional reference link to MK2 Turbo 3 Sprint full car wiring schematic:
https://www.imageupload.co.uk/images/201...Wiring.gif

[fixkick]

im sure its just a photo setup error but why is the suppressor unplugged?.. this is never a good idea...

it has to be present, or the coil primary, may not oscillate properly.
the problem with suz, schematics, some are not totally accurate
on most of these cars, there is capacitor (condenser) on the coil minus terminal to ground. (it resonates "ring like bell" electonically )

this causes the primary to ring, and make full high voltages as a resort, (as seen on old points cars, if missing this Condensor, spark will be there, but weak)
the problem with SUZ is they hide its location, (ignitor, suppressor, or just cap on the fire wall and then to coil minus. 0.1uF is typical)
it must be there, is the bottom line, some where.

in all tests the spark HV terminal fails the spark plug wire at the coil test? .028" gap or more narrow for turbo, not sure on turbo spec here.0
turbo cars run tighter gaps, or special more powerful spark setups.
do all test with the diag jumper in place, this jumper is harmless , and must be left there until engine runs good.
you have now substituted all part parts but ECU and wires., right?

hope this helps, and the ignitor needs a 100% perfect ground, or spark dies.

coil minus to ground, fire is dwell time, this is coil charge up time, the it fires and you can see it RING.


vert , 10v/div
horz, 5mS/div