4th gen tercel - location of RPM sensor?

[dlb]

i'm helping a friend with their '91 tercel that sometimes dies on idle. my pal checked the codes and '12' is the only code it gave, which indicates "Engine speed (RPM) sensor -circuit" and is caused by "Wiring, RPM sensor, ECM". but i have no idea where the engine speed sensor, aka rpm sensor, is found. i've been searching online for the last 20 minutes and can't find anything. anyone here happen to have any insight?

[marlinh]

Possibly it is in the instrument cluster.

[Petros]

I always thought that was in the ECM, that unit controls spark, so it should automaticlly know what the RPM should be. OTOH, there could be a separate rpm sensor to verify ECM signals.

If it were me I would clean all the contacts and double check connectors, and clean the throttle plate with throttle body cleaner.

[splatterdog]

It's in the distributor. Those have 2 separate pickup coils, one for rpm, one for crank position. Either one going bad will set the code.