ECU/AFM problem

VegetableOil
Posts: 5
Joined: Sun Jun 30, 2013 12:23 pm

ECU/AFM problem

Postby VegetableOil » Sun Jun 30, 2013 12:36 pm

So I've swapped a 4age into my sr5 from a donor gts that was initially not running due to what I thought was just a blown head gasket. After changing that and hooking everything up, I have spark and good compression but it looks like my circuit open relay is not functioning correctly and my injectors are not firing. The fuel pump and relay both work when you run 12v into them, and my injectors are properly grounded on the intake manifold. I have also grounded the intake manifold to the frame to ensure a good ground. This has lead me to believe that I either my ecu or my afm are not functioning, as they both control power to the injectors and COR. Before I go replacing either one of these, I was wondering if anyone had any insight as to which one may be at fault or how I could test to find out. HELP!


VegetableOil
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Joined: Sun Jun 30, 2013 12:23 pm

Re: ECU/AFM problem

Postby VegetableOil » Sun Jun 30, 2013 12:51 pm

yoshimitsuspeed wrote:http://mr-2.info/1988%20Toyota%20MR2%20Repair%20Manual%20-%20Toyota.pdf


Hmm. The troubleshooting in the efi section seems helpful. I will give this a try when I have time. Does anyone know of a more direct approach that I could try?

yoshimitsuspeed
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Re: ECU/AFM problem

Postby yoshimitsuspeed » Sun Jun 30, 2013 1:17 pm

More direct than the troubleshooting section made by the people who made the motor?

Get out the multimeter and test the AFM, per the BGB.
Use the wiring diagrams to see where power comes from and where it's supposed to go.
After that chase the circuits and see where it stops.

ga_goosh
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Re: ECU/AFM problem

Postby ga_goosh » Tue Jul 02, 2013 2:22 pm

the COR has 5 wires 3 on one side and 2 on the other. if you jump the side with 2 wires it will bypass your COR. if the car runs then its your COR. if it runs poorly then its probably your AFM. also check that you dont have any cracks in your intake tube as it could prevent the flapper in the afm from being pushed open by the incoming air. also try sticking a screw driver or something simmilar into the afm to manually open the flapper and try it to see if it runs.
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VegetableOil
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Joined: Sun Jun 30, 2013 12:23 pm

Re: ECU/AFM problem

Postby VegetableOil » Sat Jul 06, 2013 4:20 pm

problem solved today! It ended up being the efi main relay.Thanks for the help!