I Give Up - Suggestions

[Th3WhitePearl]

4 minutes ago, Bob King said:

Pity you can’t have a chat with this guy he seems to know his ECU’s…..

 

https://youtu.be/Nupy486Fz7Q?si=r8ZSJ_xXDGo0crhm

Seems to always be aimed at the 6 speed just like that video. 

I can't even be sure it is ECU related which isn't super frustrating as I can't just keep chucking money at it. 

Surely if it was ECU it would do this regardless of temp. 

 

I think I'm still leaning towards fluid again🥹

[steve2006]

The thing is with the capacitors in the ECU over time they do become thermally sensitive and their internal resistance increases (ESR).

Greater resistance results in more heat so the capacitors then begin to swell up.

Their construction is foil, paper and liquid all sealed inside by a rubber bung where the leads emerge, due to internal pressure build up the seal eventually ruptures resulting in a leak of the liquid (electrolyte) which being corrosive then attacks the copper print on the board and the capacitance continues to fall below its nominal value (i.e. it doesn’t do its job anymore).

This could explain why everything seems OK when cold but when warmed up the problems start due to heat also building up inside the ECU. Another issue is “dry joints” on the soldering again due to heating and cooling over the years.

If you want me to take a look at it for you P.M me, I’m a retired electronics tech and have repaired quite a few ECUs for other members.

 

[Th3WhitePearl]

2 hours ago, steve2006 said:

The thing is with the capacitors in the ECU over time they do become thermally sensitive and their internal resistance increases (ESR).

Greater resistance results in more heat so the capacitors then begin to swell up.

Their construction is foil, paper and liquid all sealed inside by a rubber bung where the leads emerge, due to internal pressure build up the seal eventually ruptures resulting in a leak of the liquid (electrolyte) which being corrosive then attacks the copper print on the board and the capacitance continues to fall below its nominal value (i.e. it doesn’t do its job anymore).

This could explain why everything seems OK when cold but when warmed up the problems start due to heat also building up inside the ECU. Another issue is “dry joints” on the soldering again due to heating and cooling over the years.

If you want me to take a look at it for you P.M me, I’m a retired electronics tech and have repaired quite a few ECUs for other members.

 

Very kind of you! 

I know when I had an LS400 I indeed had to change the ECU because of something similar. 

I just would have thought a failing ECU would cause more hassle than slipping gears 

 

Okay so pull the ECU out. 

Am I gonna set off an immobilizer if I remove it? 

[steve2006]

No the ECU is coded to the car so provided you put the same one back it will reset.

[Th3WhitePearl]

Just now, steve2006 said:

No the ECU is coded to the car so provided you put the same one back it will reset.

thank you! 

will have a look and see how much of a faff it is to remove it, might be able to look today if the weather keeps up