Ehemm, if it aint broke........
Right, lets take this a step at a time
1. Intake pipe, make sure it's got no breaks in it, duct tape is wonderful stuff, the more the merrier
2. How did you clean your maf? Kinda hoping the answer is bloody carefully
when you disconnected the maf did you try and drive the car? the maf's there to regulate the air/fuel mixture so if you disconnect it, it's gonna run rough (although not as bad as a goosed maf), wrong fuel/air ratio
Therefore take it for a spin and gun it, if it drives normalish at high revs it's probably the maf (gets closer to the right ratio at full bore
) if it works, i'd suggest the maf
3. You messed about with the relays
maybe take em out again (carefully) clean the contacts and bung em back in
4. The spare plug? on a 155 the spare plug next to the lambda is the diagnostic plug (i think) and normally comes with a cap on it so I think that's what yours is but still check for the wire to go with it anyway
5. The big f'off electrical connectors on top of the throttle body (well it is in a 2ltr anyway) is the ecu and main connectors, did you touch them? hopefully not
If not DON'T TOUCH IT!
6. If nec I could have a look for you, bearing in mind i'm practiced on the twinny's not the V6's or I know someone in Newcastle with a diag machine but that will cost you
Hopefully that lot helps
Please remember I mainly work on the 2ltrs and 1.8's so i am by no means an expert but all of the above can be done without causing any damage and you gotta help the local boys