I just bought a friends 760 GLE that is currently non-running. When you start it ups the idle is erratic and like "searches". It between 400rpm and 1200rpm. It does this for like 5 minutes before the car stalls out and won't start back up until its sat for about an hour. The description I got from my friend about this when it started is "just died more or less stopped accelerating or even really revving when i hit the accelerator and then kept doing it worse and worse".

Just wanted to see what this forum thinks is a good path to go down. My, unfamiliar to bricks, brain tells me to investigate fuel pressure and TPS/MAF sensors. But I wanted to see if maybe this is a commonly seen issue, or if another diagnostic path would be better than my planned one.

Thank you all in advance!