Hello,

For a week my 04 coupe w/52k had been stalling after 10-15 minutes of driving. It would crank, but not restart. After an hour of cooling down, it would start with CEL, but would only run another 5 minutes until it died again. Code was first P0410, secondary air injection system, then a few days later P0335, for CPS.

I got a Duralast CPS from Autozone. The harness plug doesn't click into position like the stock one did; it in is position, but takes little effort to pull off. I bought a K&N recharge kit and soaked the filters pretty well and followed the provided instructions. Bought used; it came with some blue Septre cone air filters.

After install, started right up with no CEL; cleared the ESP light with wheel rotation. It ran idling for a good ten minutes, but as soon as I was in gear and tried to accelerate, it got a CEL and died. I tried this a few times with the same outcome.

I bought an Autel MS310 scan tool. The freeze frame says:

DTC freeze frame - P0335
Fuel system 1 - CL
Fuel system 2 - CL
Load value (%) - 31.4
Engine coolant temp - 187

Short term fuel trim 1 (%) - 6.3
Long term fuel trim 1 (%) - 0.0
Short term fuel trim 2 (%) - 6.3
Long term fuel trim 2 (%) - 0.0

Intake manifold absolute pressure - 12.1
Engine RPM - 2150
Vehicle speed MPH - 11

This is a great site and I have benefited from it for two years. Thanks for all of your support to the community!

 

I am going to go out on a limb and say replace the CPS again with one that fastens correctly. I have used the Bosch and a Napa one that is identical (but no MB star) and have had no issues with them. Your connection may be going bad on you when it gets hot... I fought this battle for quite a while previously...

 

I bought one from Advance Auto Parts and my car would quit at 5000 rpm, more or less. Idled better than ever. I put the Bosch back in and it runs fine now.

Les

 

Thank you for your prompt responses!

I will get a new CPS from Napa; I actually went there, but they were not in stock and sold for $87. Autozone had them in stock for only $55.

Not sure where to get a Bosch, except...Amazon for $39? Bosch 0261210170.

Amazon.com: Bosch Mercedes Benz Crank Reference Position Sensor: Automotive

 

It sounds like Bosch was the original part - I think I'd go with a Bosch.

... and it's about time for me to order one.

 

Bosch $47.70 shipped 3-5 days from Amazon.

 

The NAPA part is a Bosch also.... all numbers are the same as OEM... just no MB star... yes they do run a little higher than other places.... but when I needed one they had it in stock!

 

Update: Installed Bosch CPS. Everything is great! Thanks, everyone!

 

Mike, any leak at all on the CPS will make her not idle and run rough...finally die...glad you figured it out.