High Idle Problem

Hi,

I have a Mitsubishi GTO Twin-Turbo Year 1992 also known as Mitsubishi 3000GT,

The Stock ECU broke down so i decide to upgrade with the Link ECU 4+ plug in.

The car starts fine but have around 2000 RPM at idle and notice that engine temp increased also.

After some checks , realised that if disconnect the hose of fuel regulator and leave it open the RPM goes to around 1000 RPM

The Help and Support of Link recommended to increase the Main Fuel because it could be that the engine was running Lean.

I have done that but instead of Lower the RPM it have Increase and because of i decided to try lower the main fuel.

I have lower the Main Fuel from 13 ms to 8 ms and have now a stable engine at around 1000 RPM with very low engine Temp.

I just start learning with HP Academy so i don't have the knowledge yet for Tuning my Car and need help

I just need to know if what i have done is correct and if the values of the engine on the LINK ECU log that i attached are safe for the engine.

I just need the car running Safe at the moment so i can do the Insurance drive it on the road and parked Legally.

After finish the Courses and have enough knowledge then i can do a proper Tune on the car.

I really appreciate all the help

Attached are the first and second ECU Log for analyse

Thanks in advance for all Replies

What’s ur afr at idle

Note Link dont make a plug-in ecu for a GTO so I suspect some dealer has sold you a modified Evo plug-in ECU. It should really be that dealer supporting you since it is their product and base map.

You high idle RPM is probably because your idle valve base position table is commanding the valve to be too far open. This causes the idle to be above your idle speed control RPM lockout so the ECU will never attempt to bring the idle down.

Start by changing the idle speed control mode to open loop and follow the setup procedure in the help file, this will get you a closer starting point.

Hi Adam,

Thanks for the information I will do that and see how it goes.

Kind Regards

Joao Jacinto