Buying a second ECU for a tune

[ephone]

I'm curious, does the ECU store specific data tied to your car/vin - like mileage. I am wondering about buying one, and use it for tuning, and keeping the original for dealer trips. I know they're expensive, btw.

 

[Terry@BMS]

Waste of time, unless you plan on changing every module in the vehicle. True torque/load is also stored on the transmission control module and the stability control module.

 

[G70 Owner]

True torque/load is also stored on the transmission control module and the stability control module.

So how does the JB4 get around this? Or it doesnt?

 

[Luc343]

So how does the JB4 get around this? Or it doesnt?

I bet you it does not!

 

[SafetyPilotCal]

If I remember the discussion last time this came up, it does not. You're just betting on the tech not checking it whereas a tuned ECU would be immediately obvious.

 

[Terry@BMS]

So how does the JB4 get around this? Or it doesnt?

With a JB4 the transmission, engine, stability control, only ever see the factory specified torque, boost, and load levels. That's how it works.

 

[SafetyPilotCal]

So all that information just comes downstream from the ECU (which I assume gets spoofed data via the JB4)? The TCM and other modules don't calculate their own values?

 

[Terry@BMS]

So all that information just comes downstream from the ECU (which I assume gets spoofed data via the JB4)? The TCM and other modules don't calculate their own values?

It all comes from the ECU's calculations which with the JB4 in place all reflect factory values. But with a flash tune reflect higher than factory values.

 

[SafetyPilotCal]

Thanks, Terry! Good to know!

 

[ephone]

Still curious if the mileage is stored in the ECU?

 

[jd284]

Still curious if the mileage is stored in the ECU?

they wont be able to tell. the only way to truly potect yourself is to have a spare

 

[G70 Owner]

they wont be able to tell. the only way to truly potect yourself is to have a spare

This is only correct if you ignore what Terry posted above: True torque/load is also stored on the transmission control module and the stability control module

So a spare ECU is literally a waste of money to protect your warranty

 

[jd284]

This is only correct if you ignore what Terry posted above: True torque/load is also stored on the transmission control module and the stability control module

So a spare ECU is literally a waste of money to protect your warranty

ok but what is the history of storage? I doubt it stores every drive cycle lol. I wouldn’t be surprised if it’s cleared upon battery reset

 

[jd284]

And that part is 250 on Kia website wouldn’t be too difficult to swap both if it’s programmed

 

[ScottM]

Why buy another ECU? I mean you're hoping that if something does go wrong that KIA won't be able to find out that the spare ECU that you are using is a spare. It's a mistake to assume that they won't be able to tell. This might be KIA, but they aren't going to NOT double check everything possible to get out of a claim. In any event, if you're going to mess with the ECU be prepared to have to fight with KIA if something goes wrong...no matter how much you try to get ahead of the curve (so to speak).

 

[jd284]

Why buy another ECU? I mean you're hoping that if something does go wrong that KIA won't be able to find out that the spare ECU that you are using is a spare. It's a mistake to assume that they won't be able to tell. This might be KIA, but they aren't going to NOT double check everything possible to get out of a claim. In any event, if you're going to mess with the ECU be prepared to have to fight with KIA if something goes wrong...no matter how much you try to get ahead of the curve (so to speak).

I get your point. I’m still not convinced the jb4 does not leave a trace. There is no undetectable tune then

 

[jd284]

I get your point. I’m still not convinced the jb4 does not leave a trace. There is no undetectable tune then

Also for me it is more about preserving the tune so it isn’t accidentally flashed over. Saving the warranty is just a plus even if not guaranteed

 

[ephone]

ok but what is the history of storage? I doubt it stores every drive cycle lol. I wouldn’t be surprised if it’s cleared upon battery reset

My boat has mercruiser 350 mag. I bought a scan tool for it, and it stores the hours permanently, and also records the amount of time the engine runs in different RPM ranges - which I can delete with the tool, but that info survives a battery pull.

 

[budzique]

the ECU has your vin coded to it (source), if you buy a second one, the dealership has to code it, and don't buy it used because they cannot reset them. Best bet if you want a full flash tune is to wait for 99,000 miles

 

[Yaro]

There is a way to use different ECU in your car. You don't have to visit a dealer.