Drivin a '90 245 (M47) with 164000. Running beautifully until today...twice it has dropped RPM and nearly stalled while sitting at a redlight. I didn't have to give it gas to keep it from stalling, and these RPM drops were real quick and brief, the engine recovered almost instantaneously. Didn't happen while braking, happened at a dead standstill. Fuel tank 1/2 to 1/4 full. Fuel filter and intank prepump are four weeks old. Main pump running strong (no noises, drawing good current). Crankposition sensor looks good: no frayed wires or cracked insulation. Otherwise, engine is strong, good power and acceleration. Other than these two instances, idle is smooth and steady around 750 rpm.

I have my own ideas of the usual suspects, but I trust the experts here to enlighten me. Thanks.