Another no start - Mitsubishi GTO i88

[box]

Greetings

I have just finished installing a wire in Vipec i88 into my own vehicle, a Mitsubishi GTO Twin Turbo. Vehicle has been driven into the workshop (running Mitsi ECU/piggyback setup) and the i88 fitted. This is my first Link/Vipec ECU install where no base map was available out of the box which has allowed me to start the engine and hand the vehicle over to the tuner. Very basic setup has been carried out, I have a good solid trigger signal (Triggers 1 and 2) and RPM readout with no trigger errors. All 6 injectors and coils test OK via VTS software. Upon removing the cam angle sensor (4 wire optical type sensor) and spinning the sensor by hand, I get good injector pulse, spark and RPM. I have noticed that it will fire a coil more than once in a revolution, sometimes 2 or 3 times and never in the same position. 

On cranking it will intermittently start and run rough for a few seconds running very very rich and not on all cylinders and then cut out. If I keep winding over, no fire, no start. Sometimes it will fire once and die. Sometimes an intermittent chuff out of the intake or exhaust. Sometimes it will fire when the ignition is let off from crank to ignition on. Battery tests OK, when cranking 12v internal voltage drops to approximately 10v.

Spark plugs come out wet smelling like fuel. New plugs make no difference. 

Vehicle setup:

Engine - 6g72 twin turbo with Mivec heads and factory 4 wire cam sensor retrofitted as required

510cc Evo injectors with original resistor

Walbro 255 lph fuel pump

6x AEM Smart Coils (as opposed to factory wasted spark/power transistor setup)

 

Any ideas? I'm thinking there's something funny with the ignition timing or trigger setup but I can't quite put my finger on it. 

I have attached the PCL file which I have started out with, a modified i88 base map. 

Are there any Mitsubishi GTO/3000GT base maps available? Would be nice to have something to compare to and start with. 

Thanks!

GTO no start.pclr

Edited December 30, 2015 by box

[box]

Got it going. Started fresh with a new PCL and it fired straight up.....weird.

 

[box]

And now it's broken again. Started up and warmed up twice today, went to start it just now and it's done the same thing. Using the i88 base map included with VTS software with appropriate ignition, fuel and aux. settings changed. 

Changed the PCL, even rolled the firmware back - no dice. 

[JMP]

anything strange in the runtime value screen for the sensors (water, intake, MAP, TPS)?

Edited January 1, 2016 by JMP

[Dave Kriedeman]

Hi Box,

go to RUNTIME VALUES F12 ,

go to TRIGGERS and LIMITS tab and crank the engine.

Do you get any Trigger errors.

Press the E key are there any error codes.

Pull the sparkplugs and see if they are wet or heavily carbon fouled, if the mixtures are rich and you are just doing cold start and stop runs there is a fair chance your plugs may be fouled.

Has the engine been tuned correctly yet.

Regards

Dave.

[box]

Just a follow up on this. Runtime values seemed OK, no trigger errors (well the odd error when the engine would kick back against the starter), no faults. No tuning has been carried out on the engine apart from some very basic fuel alterations. Spark plugs were lightly blackened but not excessively fouled nor wet with fuel. New plugs fitted and no difference made.  I put the oscilloscope to the vehicle and done some testing, also fitted a remote starter button so I could really see what was going on in the engine bay while cranking and carry out testing without being stuck in the cabin. 

Perfect trigger from the ECU to coils, perfect cam/crank signal and injector pulse. Re-checked spark, only had spark when letting the key go but nothing when cranking. Turns out I had 6 failing AEM coils. All of my symptoms correlated with the system voltage changing - little/no spark when cranking due to low voltage, "good" spark when turning cam sensor manually, "good" spark when the key is let off (but engine is still freewheeling) due to voltage rising to 12.x volts after cranking. As for why it started and ran fine for a couple of days - maybe it's because the car had been on a battery charger. I put the word "good" in quote marks because when compared to another, properly working coil, the spark from these AEMs was pathetic. 

6 new coils fitted and it's away, spark is perfect and it starts as it should. 

As for why the coils failed - I disconnected injectors and fuel pump when carrying out initial vehicle setup but left the coils plugged in! Coils stayed energized for a few minutes until I heard them self discharging and clicking away. Being late in the day, I disconnected them and carried on.....never did it cross my mind that I had just caused extensive damaged to the ignition coils. 

Some lessons learnt - don't overlook the basics and don't assume anything. 

[Dave Kriedeman]

Hi Box,

great news you sorted it, not so great about the coils.

Regards

Dave.

[66wedge]

What brand/type of coils did you end up putting back in Box? I only ask because I'm using their smart coils on my own build, a Mitsubishi Eclipse GSX. And actually having symptoms very similar to what you were experiencing.