Starlet GT Turbo electrical issues

I have GT Turbo starlet im currently working on that has some odd issues ive been trying to figure out, the car has idling issues with electrics on. The car has voltage fluctuations with the indicators turned on, causing the revs to fluctuate also.

and every so often the car can just die on me with no electricals on, only code i can get for the reasoning of that is trigger signal from the dizzy, so again that has all been changed but the car remains the same.

The GT never did this before having the standalone Ecu fitted.

Ive had the loom out of the car and checked all wires along with cleaning and adding grounds to try and solve the issue but to no avail, the GT is running a Maxx street ecu on 550cc injectors.

The alternator gives out a constant volatge no matter what systems are on, the ecu also has a constant voltage no matter what but the igntion coil does get affected by having electrics on.

Im new to electrics so any help is appreciated.

Hi Lewis,

So the car never did any of this on the stock ecu? Is it a new loom or the standard loom and made to fit the Maxx?

The distributor in those are reluctor so are sensitive to electrical noise etc which, if you have some voltage/electrical issues it will show in the trigger system pretty quickly.

When the car dies or fluctuates its rpm do you have a log from this and see what the ecu is seeing for voltage.

Or possibly the voltage to the ecu is stable but the voltage to the coil or injectors is not stable.

Thanks for the reply

The car used to drop idle a bit before when having the heated rear screen on, with the stock ecu but never die or have the indicators effect it like it does now on the standalone

The Maxx street ecu is wired in with an adapter harness to the stock harness

Ill be plugging the car back in to see if I can see any logs from the ecu, but of course once it’s plugged in the car doesn’t want to play ball and act up lol.

The only time I can get it to bring up a trigger issue currently is when I do 2 step with the car.

The voltage to the ecu is stable but to the fuel pump and coil fluctuates by a few volts with the indicators in use.

Sounds like the power supply to a few of the systems are not that great.

If you're seeing fluctuations are things like the coils, injectors etc but the ecu is not seeing these fluctuations then it can cause issues with deadtime and dwell adjustments.

With the trigger issue have you managed to get a trigger scope of this? The Maxx ecu has a pretty advanced trigger scope and should be able to capture what is going on.