Does any 1 know if the ecu diagnosis codes for eb xr8, xr6, fairlane, fairmont all the same or they different

From memory with the EECIV stuff, they are specific to the engine ie, V8 codes and 6cyl codes. When you extract the codes from your car, post them up and I'll give you the meanings.

They are the same whenever the code relates to a piece of hardware common to I6 & V8 eg. TPS, ACT, ECT, FP etc. Where the I6 & V8 have different hardware eg (for V8) MAF, L&R HEGO, EGR/EVP the code only refers to a specific engine (V8 in this example, but also MPEFI and even EFI has some different codes to MPEFI)