Hello.
I also have a 155 HGT and I can say that mine is exactly the same in terms of lag, assuming that you mean below roughly 3000-4000 RPM. The throttle on the car is 'fly-by-wire' (or 'electronic', as opposed to being a system of linkages). This means that depressing the pedal all the way will have no more effect than depressing it a little, assuming that there is limited power available. i.e driving at low revs. This system reduces the fuel consumption because it prevents the engine from inducing quantities of air and fuel which it can't combust at these low revs.The lag is essentially an illusion, because you expect more result than you get. You should of course find, that if the engine is over 3000RPM or so inthird gear, then opening the throttle completely will lead to a greater change of acceleration than by opening it a little. This is due to there being more power available. (You are closer to the car's maximum power band). The only question is, does this occur most significantly in third gear?, because surely opening the throttle fully in second, or any other gear at low revs will give the same lag sensation, when you realise that purely feathering the throttle would have given a comparable result?
With regard to your exhaust, if it is hanging off to the extent where there is a gap where the back box meets the previous section, then there will be a reduction in back pressure, consequently unbalancing the exhaust and inlet manifolds. This could certainly lead to a reducition in power. However it seems unlikely that it could be hanging off to the extent where it may as well not be there, and yet still be attached at all! A simple test to judge if it's still effective would be to question if the exhaust has becaome noisier (through 'blowing') or to place your hand at the pipe and see if there are gases being forded out or if they're just dribbling! Anyway, your haviong it fixed so you'll be ok!
It's a beautiful car, the MK2 HGT and I hope you enjoy it. Just remember that it's a high revving engine so don't expect anything under a few thousand revs! Oh, and GET THE CAMBELT CHANGED BETWEEN 40,000 AND 50,OOO MILES! THIS IS THE BEST ADVISE YOU WILL EVER GET REGARDING THIS MOTOR!
Surprised your back wiper motor failed that young. The hose to the washer jet notoriously blows off and wets the whole damn thing. Alternatively my friends Bravo, was diagnosed as letting rain water through a seal on the back window destroying the motor. Probably best to get one from Fiat, as it may be warrented for a year, and one from a scrap yard may be on the way out anyway! Oh and change the seal if it's broken too. It'll all be dirt cheap.
Best regards,
Kerr.
