My trac off and engine light came on yesterday. I pulled the code as 13 which is RPM signal. Any ideas on what that might be . 1993 SC 400

 

Does the engine run, has the T-belt been replaced recently? It could be out of time. 13 is for the crank sensor (Ne signal), you also have a sensor on each Camshaft (G1 and G2), which is why I asked about the timing. If all is ok I would inspect the connector on the crankshaft sensor behind the crank pulley, it can easily be accessed by removing the lower engine cover, be sure it is connected and the harness is ok. The resistance should be @ 900-1300 ohms, I would also remove it and be sure all the teeth are good on the crank (timing belt) pulley. There is one more spot and that is where the harness runs up the front of the block and the connector is at the front left of the Intake manifold, if it is ok too then it may be just a bad crank sensor itself.

 

the car runs great. Had a full timing belt service about 15,000 miles ago. I'll check the crank and cam sensors and connectors