New to this forum and am hoping someone has been through this already. I've searched most of the posts and haven't found the same exact problem.

We have a 1999 E320 Wagon 4Matic and has been running beautifully for years. However, recently the car stalled while driving and would not start again. We waited a few minutes and the car started up. That was about a month ago and the car had been fine up until now. Now, every day, the car will run for about 10 blocks or 20 minutes and stall out, same deal.. wait and it starts up again. The problem is getting worse, and the length of time to wait is now about 30 minutes. Others on this forum have posted similar stalls, but we have had no check engine light. We've done the oil change, checked the fluids, etc.. all fine. We bought the fuel filter to replace, but haven't found where it is on the driver's side.

Recently, we changed the sparks and just now, the battery. I assume that it is temperature related and some sensor is going off preventing further driving. I don't think it's a fuel problem, we only use 93 and there is no hesitation. Side notes, the A/C runs frigid, radio/CD, headlights, all stay on after the engine stall.

I'd rather not have a parts roulette and hope for the best. Does anyone know what's up, or what the next part I should replace? I was looking for an OVP and Crank Position Sensor that another post suggested, but again, we never and still don't have a check engine light.

The last random thing is that I cannot reproduce the stall in my driveway. In our last 95degree heatwave, I let it run with the a/c blasting for 25 minutes and no stall. Maybe I have just not waited long enough, or it is something else.

Thanks in advance for any of your help! I'd like to DIY versus taking it to the dealer.