S40 V40 Cars: Driving with MAF sensor disconnected

[1stVolvodriver]

Hi Guys , looking for some advice please , my v40 d 115 has been suffering from a lack of power until the turbo spools up , then it goes like normal At the mot station last week they kindly did a free diagnosis (plug in) and came up with a fault in the MAF sensor . They suggested running the car with the sensor disconnected, which I have done today , hey presto it's back to her former glory ! I removed the sensor and visually it looks spotless , but will get a suitable cleaning solvent and see if it sorts it , Main question is , is it bad to run with it disconnected as I have a long journey (160 miles) tomorrow. Many thanks for your thoughts and wisdom

[clarkey1984]

I don't know for sure about Volvo specifically but on 2 of my previous diesel cars (pug 406 and e46 BMW) running with it unplugged is fine as instead on using live data from the maf the ecu has a fail safe standard map built in which it runs from.

[skyship007]

Originally Posted by clarkey1984

I don't know for sure about Volvo specifically but on 2 of my previous diesel cars (pug 406 and e46 BMW) running with it unplugged is fine as instead on using live data from the maf the ecu has a fail safe standard map built in which it runs from.

Not sure what the ECU does in terms of the exact injection system related default program, but the default program would result in a richer mixture than normal. The big question is how much richer, cos if it's only slightly richer than normal it might be OK for quite some time.
The lack of a lean burn mode and richer mixture would not be good news in the long term.

If there is no smoke at warm idle or moderate RPM's then it should be OK for quite a while.