technovice

I have a C230k, 114k, that has been dormant for 4 years. Prepped to sit, prepped to put back on the road. Runs STRONG! No engine power issues. When turbo kicks in it jumps up and goes! Ran 100+ miles in a week. No symptoms of any sort that would indicate EGR malfuntion. Check engine light shows P0440 code, not present before storage. Needs to pass emissions next week. Not a mechanic but he ran through all the trouble shooting possibilities, cleaning, soot in tube, solanoid, vac etc,etc. I read everything I could find including that maybe it's a false code but all speculative, nothing definitive.The simple solution is replace the EGR. Good luck! Up and down and all around for weeks, new, used. Nothing. Questions:1) Does anyone have a source for this little bugger? 2) Are EGR's from any other models or years interchangable? 3) Is there some diagnostic ideas to validate that the code is accurate and that it actually is a FAILING EGR? 4) Is there some method to rebuild/refurbish the EGR? The strategy to reprogram the EGR out of the system is beyond my techs pay grade and sounds like trouble. As an aside the dealer techs were less than helpful on providing any info. Apparently their brains no nothing about nothing before 2007. This car was built before these guys were born. Any help to get me on my road trip to Florida will be much appreciated!

tyabnet

(side note, its a supercharger, not a turbo. No lag)

P0440 is generally related to the evaporative canister - reported by a pressure sensor associated with fuel tank evaporative system. Generally it means there is a leak in the fuel vapor system - can be a hose, fuel cap, fuel fill line, even the canister itself if folks overfilled the tank too many times. So so on. The pressure sensor itself can be bad or blocked or have a poor connector. If you look at the EPC/WIS you can follow the lines that need to be tested. I myself have been lucky and we have not had to track down a 0440 code on our 230k. You referred to a "he" above, I'm assuming you have a friend helping you out.

It appears that you need someone that can help properly diagnose this. Searching around I found these:

German Auto Repair in Watertown. https://germanautorepairllc.com/mercedes-repair/
Roggi's Auto in Hartford https://www.roggisauto.com/mercedes-repair-service/

That said these cars are getting old and replacing of most of the hoses is just a fact of life. It is so easy for a minor crack on the back side that you can't see in a hose to affect many things related to emissions.

Let us know how it turned out.

technovice

Thanks Tyabnet for the ideas and the referrals. Still working it. Time to find another tech. Best tp you. Dan