electrical fault AFM please help :) - Toyota Nation Forum : Toyota Car and Truck Forums

fishbert · 03-26-2010, 12:17 PM

hi ive been having a problem with my afm,

when the afm is plugged in the car will run for 15 seconds then cut out, it does this every time. the afm was tested and the readings were all correct but decided to replace it any way. with the new afm the car behaves exactly the same. after further testing i have found the car will run if i disconnect 1 wire from the afm. (its grey with a black line and small brown bands. its the second wire in looking from the front of the car) but it runs n limp mode, connect it back and it dies after 15 seconds again.
does anyone know what this fault is, whats broken or how to fix it?
the manual suggests a faulty afm, a short in the circuit of faulty ecu, ive tested 2 afm's checked the wiring for shorts.

thanks in advance for any help

pete

93celicaconv · 03-26-2010, 01:26 PM

OK, help me out here (I'm feeling stupid). What do you mean by "AFM"?

fishbert · 03-26-2010, 01:48 PM

might be my fault, forgot to say its a 1993 gt4 import.

Air Flow Meter, its the sensor attached to the airbox which leads to the turbo

jlspec · 03-26-2010, 03:49 PM

It looks like your AFM is worrking correctly. It could be another sensor that uses the signal from the AFM and that unit is faulty.

fishbert · 03-27-2010, 06:30 AM

any idea on what sensors are connected to the afm? i know the wiring leads to the throttle position sensor and another little one behind the coil pack with vacuum pipes to it but when i disconnect those i get the same problem of the engine cutting out but i get different error codes.
the more im looking the more it looks like its the ecu but according to a toyota specialist they rarely break.

***MR2Jedi*** · 03-27-2010, 01:27 PM

With key in on position and engine NOT running, open flap in AFM and listen for the fuel fump to kick in. If fuel pump doesn't kick on, there's your problem. If it does, test fuel pressure while in this mode.

fishbert · 04-14-2010, 02:50 PM

hi,

i tried opening the flap like you said and i didnt hear the fuel pump kick in, if this is my problem how do i resolve it??
i did try holding the flap slightly open with the engine running and it would idle without cutting out

but soon as i applied the throttle it died.
this is really starting to annoy me now, i just want it running.

***MR2Jedi*** · 04-14-2010, 04:43 PM

If you own a MultiMeter and a service manual , check the TPS.