Black Mk2 GTO for sale - Currently non-runner with 2cyl misfire

…but otherwise could be put back on the road pretty easily.

Collection from Essex.

All details on eBay listing here…

Currently a bargain, definitely worth more than that.

Yeah, for the right person who can fix that misfire it could be a bargain. Else it’s a 1.7 tonne paperweight taking up space on the drive!

Have you tried to diagnose the misfire?

Yup, misfiring cylinders are a pair on a coil.

Swapped the coils and misfire stayed on same cylinders >> not the coil
New plugs & leads >> no change
Swapped out the PTU (for a borrowed one from @GSXRKID and also a newly bought one) >> no change
Removed ECU and had it refurbished by ECU Dr >> no change
Swapped it out for a borrowed ECU from ECU Dr >> no change
Hence concluding that it can only be wiring loom between ECU & PTU or PTU & coils

Have you tried a leakdown test and compression test?
To see if the offending cylinders are not down on compression and valves are closing properly?
Ok you tried the electrical stuff but not the mechanical stuff.i dont think that is wiring issue to be honest.

In fairness no, I’ve not checked compression but the misfire started instantly on both cylinders so it would be odd if they’d both suffered a loss of compression at the same moment.

I note the auction is going reasonably well, and I hope you are rewarded by the auction close.
For any potential owner, apart from any electrical suspicions, I would be inclined to double check your plenum intake gasket, and ensure there’s no air leak.
What cylinder numbers are involved?