I have a 95 R129 SL320 I found that the Fuel Pressure Regulator was bad, replaced it and everything was working fine for a few months then the same symptoms showed up and the engine would conk out and die in the middle of the street. If I would wait for aprox 3 to 5 minutes then try to start it up again, I could get it started and going no problem. Then it would go for another few days or weeks and then bam, would be driving along and all of a sudden it would die again.

I have Replaced the Fuel Pump, replaced the Fuel Filter and replaced the fuel pressure regulator twice and the same problem is back.

I've even ran a diagnostic test and no codes show.

Thanks for any Help, this is really becoming a nightmare. I can be reached at david_reeder@sbcglobal.net