Hello all!

I bought a E350 Bluetec in November 2021 in Vancouver, BC. Car has been absolutely fantastic. Got a CEL light last year in September. Used my families STAR tool to scan it and it showed an EGR error. Called Mercedes and they said they will fix it for free under the Bluetec Field Measure. Got fixed in October, and everything done for free as promised. That's when the problems started. About a month after fixing it I noticed that the engine starts at 700 RPM for cold start. Upon running for approx 15 min, or the temperature gauge reaching 80+ C, the cars rpm drops down to 500-525 when idle. 500 is way too low and you can feel vibrations from the engine in the brake pedal, the headrest everywhere. Its very frustrating and uncomfortable and I can't imagine that its good for long term engine health. Coincidence that this happened after the bluetec field measure? I called my own personal mechanic, and he tried to tell me that its the engine mounts that are going out. I told him no way because the cars mileage is relatively low (around 130k) and it feels 100% fantastic during cold start at 700 RPM. Kind of felt that he just tried to make some money so I said I'm gunna go back to Mercedes and see what they can do. Explained the problem to the service advisor thoroughly and he seemed to understand. Told him my main concern is the low RPM of 500 at idle. The CEL light at this time was also on but I didn't scan it. Got the car back today from the dealership and read what they did. Apparently the CEL was for the Adblue tank heater going bad. They replaced that free of charge. Upon further reading the report I noticed the legendary "Unable to confirm rough running". Great. Not only did they fumble the mtce of the vehicle and kept it for 4 days in order to replace the heater, but they didn't do the one thing that I asked to be fixed.

Has anyone have similar issues? I see everywhere people saying that the RPM runs higher after start and thats due to A/C and I wish I had that happen. But instead mine runs at solid 500 RPM causing rough shaky vibrations. After this fiasco with Mercedes and the adblue tank im considering going to Malone and completely pulling the entire Bluetec system out of the car to prevent further headaches in the future, but would like to fix this engine RPM problem first. Any advice?

 

Wouldnt pull anything right now because u just got the extended warranty. Make them fix it assuming it happened when ya got it back from the field service its related. Something didnt get put back together correctly.

also there is a diesel section, not alot of diesel input in this subforum.

 

any resolution on this? i still have my 2002 ml320, but recently my son picked up a beauty, same as yours except it's a 'blue efficiency' (gas). he said that car runs great, but stalled out at stoplight tonight. not sure what the rpms are at idle in park, and in drive with foot on brake. we'll see, but just thought i'd hit you up for any suggestions. thanks!