My mates 95 Classic import has developed an interesting problem...

It was running fine for a while and then it started loosing power and jumping. It would normally hit boost about 3000, boost gauge shows boost (approx. 16/17 PSI) but it goes nowhere? It then tries to pick up at about 4500 again and just starts jumping as though it is trying to pick up and fails. Boost does not show any drop off either.

A new MAF was fitted, boost solenoid checked, K&N was removed and put back to panel filter and still not working. The engine was re-built a few years back but was fine and pretty quick!

Fuelling problem maybe??? He is a bit sick of spending on bits for it to make no difference!!

 

It might also be a knock sensor detecting knock (real or otherwise) thus making the ECU retard timing. You can try disconnecting the knock sensor and then testing it for a short time.