Recently purchased a well maintained, 150K, '87 300D. Drove back from TX to PA and car ran great. Over next few weeks, started running poorly, slow acceleration, poor fuel milage.
Tried all the fixes that work on the '83, but little improvement. New calibrated injectors, fuel filters, air filter, cleaned vacuum control lines, checked switchover valves, pulled and desludged intake manifold and air pipe, cleaned over pressure sensor, disabled EGR, and ran Diesel Purge through system. Some days runs better than others, but always has a noticable lag in acceleration at approx. 2000rpm under full throttle. Any suggestions?