Does anybody know if an ECU from a manual GT needs to be fitted when carrying out an auto to manual conversion? I've heard people saying no, but I don't understand how the car is supposed to run right with a 5 speed manual gearbox when using a 4 speed auto ECU? We have done this conversion and running the Auto ECU as advised, but the car is not as quick as it should be. It doesn't hit full boost, only gets to about three quarters of the way up on the stock boost guage. It also slightly judders at about 2200 revs for a split second. I have changed the spark plugs today even though the car has only been serviced recently but the judder is still there. The engine management light is also on but I'm told that's because some of the sensors that belong on the Auto box are not connected up? Gonna get a diagnostics test done this week anyway. The car is completely stock with the stock BOV removed as I broke the fixing on the EFI pipe. I will be getting an aftermarket one for it asap. Any ideas would be great! Does anyone also know if the manual ECU will plug straight in? I don't think it will but someone will know better?! And if not, can the wiring be modified to fit or will I need the manual wiring loom?