2000 E320 w/94000 mi on clock, have had intermittent problem with car failing to start, mostly when hot. Had codes pointing to O2 sensors, which I changed all 4 yesterday. Today on shakedown ride it wouldn't start after being stopped for 30 minutes (still hot engine). Engine spins very well with starter, but seems to either get no fire or no gas.Came back to it a couple of hours later and started right up.
Also recently changed out the key batteries, as a previous post pointed to that.
I just ran the codes and still has a (residual?) PO161, but haven't cleared codes since O2 sensors replaced yesterday. Any ideas??? Thanks in advance...

 

Probably could have saved you the sensors yesterday!Did you hang onto them?
If so mail them to me for the advice I am gfoing to give you.
Crank position sensor.About $67 at www.autohausaz.com
diy on benzworld.org w210 section
and mercedesshop.com diy section.
when failing and at operating temp it will either stall or fail to start at times until cooled off.easy diy with a good flashlight and the diy.

ohlord
If you have the o2's send them to me and I will install them in a needy persons car.

 

Agree ith Ohlord.
99% Crank Position Sensor.
Well documented issue under "Crank but No Start".
Usually shows up when engine hot and "self corrects" when cold.

Codes pointing to O2 sensors?
What codes other than P0161. This refers to a sensor 2 bank 2 only problem. Did you clear and determine whether it returned before taking action?
The code may have been set years ago and never cleared!

Sounds like Ohlord can find a use for your displaced sensors.
O2 sensors are extremely reliable. Usually failure mode is contamination in various forms.

Stuart

 

Stuart and Ohlord, thanks for both the responses. The car had thrown other O2 sensor codes previously. I would reset to see if they returned, which they did. The PO161 was either the only residual or a new code with the start failure yesterday. I think the old sensors are marginal at best, but will be happy to send them to you if you really can use them. The car has 94K on it and the sensors are original to the car, I think.
Thanks again.

 

That's okay.
Replace the CPS make sure you order the crank position sensor as there is anothe cps called the camshaft position sensor and that has different faults and symptoms.
ohlord

 

my 99 e320 had the same problems would stall when hot and would not restart. Changed the cps and have not had any problems since. It cost about $77 for the sensor plus shipping. Definitely would give it a try. Takes about ten minutes to change.