Hi all, just got round to taking the dashboard out to see why the EML light didn't come on with the ignition - had been removed by some PO (plus the bulb holder). I now have the following codes: 15 (engine coolant temp sensor), 16 (boost air temp sensor), 41(main throttle solenoid valve).

I checked resistances of the sensors and think they are ok (ignoring throttle for now). Working through the flow charts in 13I-13, find that there is no continuity between the air temp sensor and ground on pin 2, but correct voltage on pin 1. For the coolant temp sensor continuity on pin 2 to ground is ok, but get no voltage on pin 1. Someone has messed around with all the wiring around here - the proper plugs are missing from the EGR valve and another connector (but not the ones in the error codes), and wiring to the air temp sensor has been resoldered. I'm hoping they made a mistake and wired it up wrong, rather than the ECU being duff.

I am thinking it may be worth checking if the sensors are connecting to the correct ports at the ecu (all 3 problems have 'check connector C95' in common, the two sensors say check C51, C95, C97). But I am completely stumped when it comes to figuring out the wiring diagrams. How do I check these connectors? Is it worth it? or is this likely to be a duff ECU?

Sorry for the long post, any help would be welcome.

more than likely wiring related and not the ecu but take the ecu out and inspect it for signs of damage

Good call Chef - found two disconnected wires in dodgy PO rewiring. Sensors now working, no error codes and no white smoke from cold start! very happy.

glad it was a cheap fix mate