I've posted this question before but still haven't managed to solve the problem. The engine warning light comes on intermittently on my
1991 3000GT SL. I did a fault diagnosis of the ECU as described in the service manual and found malfunction code 14 for the throttle position sensor.
I checked the throttle position sensor (TPS) and the idle position switch with a VOM but both components seem to be working OK (as described in service manual) . Not sure where to go from here. The fault is intermittent and when it occurs the automatic shifting becomes erratic. The fault ONLY occurs when engine is warm (after about 1/2 hour of driving).
Someone previously suggested that it may be an earthing problem so I renewed the earth straps from the battery to the chassis and engine. This didn't help. Any further suggestions? Should I assume that it is the TPS and replace it anyway? Maybe the intermittent nature of the fault makes my checks of the TPS with a VOM invalid.