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Chris (aka-Moose)
Chris (aka-Moose), Auto Technician
Category: Toyota
Satisfied Customers: 877
Experience:  16 years of experience
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camry: cyl..vacuum sensor..comes back..i have left is the ecm

Customer Question

I have been getting a code 31 on a 93 4 cyl camry, i replaced the vacuum sensor, cleared the code and it comes back but will go away sometimes. when i get the code the car will bog down. all i have left is the ecm, is there anything else that could be wrong?
Submitted: 8 years ago.
Category: Toyota
Expert:  Skyvisions replied 8 years ago.



You have many options with today's internet so Thank you for choosing


It is unlikely the ECM have you checked the voltages for the PIM signal input at the ECM. The only way to get this code is if the VC or VS is getting grounded or going open. Did you check the pin fits at the ECM and the sensor connector. Click the link below for the wiring diagram. The computer outputs a 5 volt VC reference signal then as vacuum changes on acceleration the signal voltage changes. On page 2 of 7 the B/Y wire is the signal wire the voltage has to fluctuate on this wire. Check that there is continuity on the brown E2 wire. Voltage should be less then .01 volts. Let me know what you find.






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