406oc.co.uk

406HDi 2.0 110BHP 1999.

Has very little power and often won't go above 2,200RPM. Have cleaned Throttle Sensor and power is a lot better lower down the revs, but still won't go avove 2,200rpm. Amber Diagnostic light ON.

Could it be the MAF sensor? - I've checked the connection and found the following:
Pin1: Yellow, 4.9V with IGN ON
Pin2: Pink, 12V with IGN ON
Pin3: Orange, Ground
Pin4: Green, not used
Pin5: Red, Ground
Pin6: Green

Any thoughts?

Regards

The MAF sensor doesn't normally give any trouble but the throttle position sensor does.

Check the engine bay fuse box too, I had a big fuse (as marked white, serving the radiator fan) which was getting hot and pulling too much current and flagging the engine light. Sounds weird but true.



To be fair you won't really know the cause without a code read

Does it recover if you disconnect the battery then turn the ignition? I had this on a Berlingo, it was the egr valve and the throttle pot.

After reconnecting the battery.

Thanks for all of the info/hints.

First the good news. I've bought a new MAF sensor and fitted it - it has made an incredible difference. Now I can hear the turbo kick in and it revs way behond 3,000 again. Car runs great again - well it did ...

Second the bad news. While messing around and checking everything else, I've discovered the sensor at the top of the intercooler (MAP?) has fractured where the small tube goes into the sensor that sits in the pipe from the intercooler to the engine. I am struggling to identify the correct replacement part number. The sensor fitted is a DENSO (Japan) 5V (NO 079800-4480). The connector has three wires and they are coloured White, Green and Yellow.

Is this an original part because it seems strange that they would be using Japanese parts on a 406 when everything else is Bosch/French?

Appreciate any help again on this one.

Regards