still tinkering with this ,trying to find out how things work and how to test ,,useing one of the middle power wires on the maf back pined off the maf plug I was able to get a read off the two outside wires but no veriation when rev the engine, still try to work out why the engine stalls and stutters
car runs better with maf disconnected, got a second maf delived the other day , car went straight to limp mode a through up a code 24 , cleaned maf with maf sensor spray still no joy, the other maf was causing car to stop and start not doing the tail shaft any favours so put the maf in thats been there for 6 months and no differece if its pluged in or not .
Sunday, August 27, 2017 - 11:36 am, by: Mike Beck(Gold_40gt)
If the air flow meter is disconnected, the ecu runs a default fuel map and fixed intake temp reading and only alters the mixture based on throttle, or TPS position.
Usually in this state the engine runs leaner and timing is advanced so it makes more power oddly enough.
Air flow meter is there to make it run more smoothly, efficiently, emissions and fuel economy wise.
You can't clean these old types as they run a thin film metal mirror that is impossible to clean properly given the design, they just get dirtier if you try in most cases.
The only types you can clean are MAF hot wire types from new generation 1uz 1995+
Error code 24 just means theres no temp sensor. Pull EFI 30a fuse (green) to clear the codes.
In your case, you'd need to find a good condition AFM, not run it at all, or get a AFM delete kit, that adds a MAP sensor and aftermarket piggy back ecu, they aren't cheap, but you can gain performance using them.
thanks for your time and effort to respond on this ,I've just returned two maf's I got from the states all up $180 , I have since sorted another two one from victoria $100 ,and another from the US for $50 , if these don't work out I have come across some after market new MAF starting at $125. plus $65 postage. Cheers Pat.
I'm up dating what had happened, after much frigging around replacing caps and rotors , fuel injectors Mafs and air intake control sensors two things that were the problem, first the coils caused the rough idle you can pay between $25 to $250 for these and the cause of the stalling ,The Temp thermal sensor with the green cap and connector that lives under the top coil on the 1992 December model Sc400.