G35cJ

Have not been to the forum for a while, just want to share my recent experience with the start limit with my 09 ML320 with ~ 90K miles. I have been driving with the check engine light caused by the Adblue tank failure for about 30K miles. The Adblue tank developed a bad leak but I just add the adblue at a more frequent intervals and the car just run fine until last month it displayed first it needed Adblue but after I filled up the tank, the display changed to limited start. It allowed 20 starts. So I went to a shop and it quoted me 30K plus for a new tank. To put in a new heater seems to be a DIY that I can handle, but at the mean time, I want to somehow get the start limit resolved first. Long story short, I got the OBDII plug off ebay and the darn thing worked. It is not cheap at about 300, but at least I don't have to worry about this for the time being and gives me time to figure out how to fix the stupid adblue than system.

I am speculating there is a clog somewhere in the adblue system, since the leak appears to be outside the tank. The urea has been pumped out and then not going where it should and literally crystallizes on top of the tank. This may have nothing to do with the heater I am thinking. Anyone has similar problems?

kajtek1

I had starts limiter due to ox sensor, but I replaced the sensor and had dealer reset it.
You choose not to disclosure your location, so hard to help you with proper advise, but what cost 30 Grands???
The tank suppose cost about $3000?
Than lot of Bluetec owners, who don't need to smog their cars got feed with those issues and do DPF and DEF delete.