Bad cluster, ECU or something else?

[Gazeebo]

Hello guys, I got a 90 LS400 with a weird issue. Instrument cluster lights up BUT tach/Speed are below 0 (they do jump a lil bit when tapping), temp gauge is EXTREMELY slow, odometer and trip meter are stuck also. I'm getting a code 42 (speed sensor 1) which I replaced and solenoid 4 (after fixing solenoid 2 and 3), I recapped ECU with the appropriate caps and I changed the speed sensor also but nothing. Car drives EXTREMELY lazy and shifts weirdly, it's not daily drivable basically. 

I was thinking it drives so bad because of the faulty speed sensor (ECU won't know what's going on without it I think) but after replacing it and having the same issue I think it may be cluster related. Would changing instrument panel capacitors help with this? is it possible bad caps affect signal going to the cluster which in turns affects ECU signal? I'm lost honestly. Any help would be great in order to get this car daily running again.

[chc0318]

I suggested you fix the instrument panel capacitors first.

[Gazeebo]

15 minutes ago, chc0318 said:

I suggested you fix the instrument panel capacitors first.

I got the cluster out, I plan on changing every single capacitor in all boards (even in the needle boards)

[sha4000]

Great, let us know how it goes.

[Gazeebo]

Update actually: 

 

Found 1 leaking cap (from below) on the small board inside the cluster. Mounting it up hoping it fixes the speed sensor code. Broke my tach needle also 😞

[sha4000]

Sorry to hear about the tach.

[Gazeebo]

Update:

Nothing changed, bought a used ECU and cluster to changed both things. if same issue occurs I bet it must be bad wiring somewhere.