'99 606 shutting down
 

Good morning All!! Over the years, I have gleaned Tons of valuable and applicable information from this forum...Thanks to All of you for your input!
I have a 99 E300 606TD. I have done a CAT delete with open exhaust, Full EGRectomy with the resistor mod and it runs Amazingly well but I've also tried to accomplish the MAF delete with the resistor but am still running into code issues and limp mode. The MAF delete thread kind of died years ago and I need to revive it....if anyone can help.
I'm also having a new issue that just started recently......you can be driving normally....maybe 10 minutes, maybe 30 minutes and it just shuts off....nada, done, dead and won't restart for hours.
I did some digging and found a possible problem being the K40 relay assembly. Apparently on the gas cars, this relay controls the fuel pump and the diesel models it operates the fuel shutoff valve and is prone to failure after a lot of years. Anyway, I ordered a new one and installed it with high hopes, but still did the same thing!! Does Anyone have any ideas on what might be causing this?
Help is MUCH appreciated!!
Thanks!!