Replacing ecu (3.8 auto)

[ConnorJames05]

Hey guys,

Replacing my ecu since it’s gone haywire, won’t read through the obd2 scanner, keeps causing misfires and trans shifting issues but goes away when reset then comes back.

I’ve read I need a tech2 to pair the ecu and bcm together, will any other scan tool work? Or is there anyway around it?

Cheers

 

[lout]

vident 400 and maybe others

 

[ConnorJames05]

Hey guys,

Replacing my ecu since it’s gone haywire, won’t read through the obd2 scanner, keeps causing misfires and trans shifting issues but goes away when reset then comes back.

I’ve read I need a tech2 to pair the ecu and bcm together, will any other scan tool work? Or is there anyway around it?

Cheers

If it helps, I have an ichecktmps obd2 scanner at the moment. I could probably get a better on if need be

 

[Lex]

Hey guys,

Replacing my ecu since it’s gone haywire, won’t read through the obd2 scanner, keeps causing misfires and trans shifting issues but goes away when reset then comes back.

I’ve read I need a tech2 to pair the ecu and bcm together, will any other scan tool work? Or is there anyway around it?

Cheers

What have you done to sort the misfire & trans shift?

 

[ConnorJames05]

What have you done to sort the misfire & trans shift?

Plugs, leads, throttle body, coil packs, coil bracket. Nothing for the trans since there’s not much for us todo that we know.

 

[Lex]

Plugs, leads, throttle body, coil packs, coil bracket. Nothing for the trans since there’s not much for us todo that we know.

Depends on what is wrong with the trans?

But in some instances changing the tps will fix the trans shift?

Misfires.
Checked the dfi plug?
Have you checked the dfi wiring loom?

 

[ConnorJames05]

Depends on what is wrong with the trans?

But in some instances changing the tps will fix the trans shift?

Misfires.
Checked the dfi plug?
Have you checked the dfi wiring loom?

Yeah we’ve had some of those checked through, only reason I’m pretty certain it’s the ecu is when the computer is reset, it runs absolutely perfect for a few hours, then comes back

 

[lout]

when you reset the computer it clears the fuel trims
then after a few hours it has relearnt the fuel trims
try unplugging O2 sensors and drive like that for a few days

 

[ConnorJames05]

when you reset the computer it clears the fuel trims
then after a few hours it has relearnt the fuel trims
try unplugging O2 sensors and drive like that for a few days

Which o2 sensors? Or all/both exhaust and intake? Also, will it damage my engine doing short trips with it missing?

 

[lout]

there is a left and right O2 sensor in the exhaust pipes near engine
car will use its default map which is actually very safe
check engine light will be on, but nothing to worry about