After replacing my timing belt (and checking it twice) I noticed problems at high rpm during acceleration. My '92 745 (B230 engine, REX/Regina, 130K miles) starts up and runs nicely --- until engine exceeds approx. 3600 rpm under load (acceleration). At 3500+ rpm the engine loses power and the tach "flutters" between 3600 and 4000 rpm. This occurs in all gears (e.g., when accelerating from a standing start or during auto transmission downshift during highway speed acceleration). When I stop accelerating and rpm drops below 3600, the engine runs fine. I can cruise at 70+ mph all day without problem, but cannot accelerate "rapidly". In my estimation the symptoms appear to be ignition related vice fuel.

So far all my troubleshooting has been fruitless and cost less than $70 plus my time. Here's what I have done to date (not in order of performance): 1) replace fuel filter (it had 50K miles on it), 2) replace spark plugs (old ones looked good after 40K miles and the engine uses no oil), 3) replaced "aftermarket" rotor and distributor cap with Bosch OEM parts, 4) verified the timing belt was properly installed and tensioned (verified timing marks on cam gear, aux gear, and crankshaft), 5) performed "darkroom" visual verification on plug/coil wires (wires are Bosch OEM and less than 8 months old), 6) with transmission in park accelerated engine to 4000+ rpm without any sign of problem, 7) verified that the diagnostic system had zero stored error codes (both fuel and ignition codes were 1-1-1 meaning there is no stored fault).

I intend to replace the plug/coil wires next.

Anyone had similar problems or experiences? You insights would be appreciated!!