By dave on Thursday, September 27, 2001 - 01:36 pm: Edit

Is there any way to test a air flow meter from a Disco without just buying a new one to 'try it'?

I am trying to troubleshoot a problem with our Disco and all signs point to the AFM. Anyone have a spare they want to rent out? How about someone in the Orange County area that may let me try there AFM for 10 minutes?

Thanks

By Robert Mann (Oldscout) on Thursday, September 27, 2001 - 02:10 pm: Edit

I do not know if this will work, I got it out of my old notes from a Bosch EFI class I took. I only have the Haynes manual for my Disco and it is a POS.
This test works on about 90% of the flow meters.

1)With key off, disconnect MAF connector. Connect DVOM between A & B at vehicle connector harness. Test voltage with KOEO. Readings should be at 10.5volts or greater, if not their's a fault in Vehicle Power Wire(A) or ground circuit to battery(B)

2)Key off, disconnect MAF connector. Connect DVOM between C&D on meter and also between D&B at harness connector. Results should be 10000ohms or greater. If not suspect fault in wiring to control unit or faulty control unit.

3)MAF sensor connected. Backprobe MAF sensor connector between MAF and battery negative(-) terminal with engine running. Results should be between .2 and 1.5volts DC. If not MAF sensor may be faulty.

KOEO=Key On Engine Off
DVOM=Digital voltage ohm meter