Tilac are you talking about the same thing .My accumulator is under the trunk floor along side the filter ?. Fuel pressure regulator is under the airfilter .If it has fuel dripping from the small pipe after you remove it , or leaking in to it . Then its shot.

Pull vacuum line on fpr if it smells of fuel the diaphragm inside has failed. Replace fpr. My 94 m104 had similar issue, vac line test failed, replaced fpr and now starts immediately. Good luck!

FPR under the air filter. Always had a bubble of fuel in the clear plastic tube. Changed it out, no more fuel in line but no difference in performance and/or starting. Haven't touched the accumulator but have changed filter as required by MB schedule.