Code 13


New Member
hello,i just got code 13 on my 1990 lexus,,and the car star but once in a while it shut off nad the RPM idling keeps going up and down ,but it still running,,i need help i dont know what to do or what part to buy!!
Have any of yous have this problem?


New Member
I also have the EFI 13 code which translates to RPM signal no.2 which is an issue with a cam sensor although mine measure as OK. To test you just check the resistance of each one, they should be between 950-1250 OHMs.
It seems that various other problems can bring this error up.
I'm currently thinking mine is either the Air Flow Meter (AFM) or the ECU. Unplug your AFM and you'll probably find the car runs ok but uses fuel more heavily.



Well-Known Member
I recently had a van with a code 13. Checked the resistances and they checked out fine. Checked the wiring from the sensor to the ECU and all fine there. Scoped the signal from the sensor and that was ok too. I had a spare ECU to try yet still had a code. I could unplug the suspect sensor and the vehicle would still ran but when unpluging the other sensor the motor would stop. When I pulled it apart I found when the someone in the past had done the cambelt the wiring to the cam sensor was not secured correctly and it had rubbed on one of the pullies allowing the wirings to short out at times. It was a pain pulling the sensor out with the 1uz in a hiace but I was happy to find the problem. If its giving a code 13 then check that sensor really well as I have seem the same problem several times since. Cheers


Active Member
like gloverman said code 13 is cam sensor
not tps not air flow meter
erase the code and test again if it comes up then there is a prob in the cam sensor
not sure which side as cbf checking my code book

anyway 90% of the time code 13 is timing belt out a tooth or more
10% of the time its damaged wiring around the front of motor cause whenever u do a timing belt or water pump u need to pull the black plastic bits off the front
well i have never seen these put back together like factory
and ive prob not put them back together like factory either
but u need to cable tie the wiring out of the way from the serpentine belt as it comes close

anyway just buy a sensor or pull sensor out and check for rubbing thru the outer rubber cover or the shielding on the section that runs near the serpentine belt