'06 E350 wagon turns on/off while driving - PeachParts Mercedes-Benz Forum

Volvo Diesel · #1 06-21-2018, 05:51 PM

The car is a 2006 E350 (non-4matic) station wagon w/ approx. 116,000 miles.

Several times over the last few months, while driving, the car will shut off for a second (literally) while driving. When this happens, all the dash lights illuminate like the key has just been switched on or off and, after a split second, the car continues on as if nothing happened. There is no need to cycle the key, it just turns back on by itself. It has done this on the freeway, on city roads, under acceleration, while coasting--basically under most all normal driving conditions. It has also stalled at a stop light on three occasions during this same time period; during those instances, it requires cycling the key to turn the car back on. Always starts up immediately. Check engine light is not illuminated.

I had an indy look at it and they said, "no codes and we have no idea--dealership time." Called and made an appointment with MB Austin, who are generally very good. They said they scanned for codes and got nothing, checked fuel pressure and found it to be 28, which they characterized as "quite low." I had also mentioned a gas odor after filling up and they found a recall for the tank (which was cracked) which includes the pump and filter, so all was replaced and even diagnostic time was covered. Was very happy about that; in fact, almost every experience I've had with that dealer has been positive. Tech said he felt confident the random cutting out was caused by the failing fuel pump. I was hopeful....but a day after getting it back, it did it again. Drat!

Seems to happen while the engine is up to temp. Car drives very well otherwise. Both batteries replaced within last 9 months. Has happened with both keys. Idle is smooth; maybe a very, very slight fluctuation in drive when stopped. Car always starts right up-no instances of extended cranking, ever. Only other (possibly related?) issue is a very slight pop occasionally from under car. Could be a very faint misfire, maybe. My kids joke there is an elf that lives under the car and knocks once on the underside occasionally to annoy us.

I'm going to check the main battery connections, and the dealer wants me to bring it back on Tuesday. Trying to gather information and curious as to whether anyone here has seen or experienced anything like this. Crankshaft position sensor maybe? Crank position sensor and cam position sensors are original to car. Cam position sensor wiring harnesses were replaced under recall/warranty in 2013...

Thanks for any ideas...