My Zafira 1.8 petrol with gas conversion feels very underpowered and really choked.(it sometimes judders/surges slightly on aceleration)
I have cleaned the throttle body, (In place though) couldn't get it off.
I dont think I have an EGR?
Its just been fully serviced (as it always is from new)
The temp gauge takes a little while to come up and under the right conditions runs slightly hot. i.e. sat in traffic, switching off and then back on after a long run.
My coolant needs topping up every 1K. not much but enough to be concerned.
I get no fault codes using my elm327.
A local tuning centre detects Cat efficiency and suggests I change it: £250 +fitting
The oxygen sensors 1+2 seem to return normal values and are responsive.
The MAF also seems to respond well to engine revs.
The car is running lean according to the MOT emissions tester.
What do you reckon Cat or is that a red herring.
I would really appreciate some feedback.