Engine oscillation on abrupt throttle
I seem to have a slight issue with my phase 1 twinspark. If I suddenly floor the throttle (either in gear or when changing gear) then I get a feeling like the engine torque output oscillates for a couple of seconds before settling down and consistently pulling hard. If I'm slightly more careful then I don't think I can fault the performance and will eagerly rev all the way to the limiter in 2nd and 3rd.
The resonator is present (otherwise I could believe this was an intake resonance playing with the MAF if it had been removed).
Anyone with any ideas?
- lamda sensor?
- blocked/dirty air filter?
- leak in air feed?
- resonator actually filled with expanding foam?
- can an engine mount cause a wobble in output?
The only other thing is that sometimes it might sit at very low revs for the first second or two after starting before settling to its normal idle speed.
2002 156 Lusso 1.6TS Grigio Metallic
2008 147 Sport JTDm 3dr Grigio Strombolli
2014 Giulietta 170 Multiair Exclusive Alfa Red
1997 Spider TS Alfa Red
201? Giulia 2.0 Multiair Super Alfa Red