I have a 2018 Mercedes Benz GLC 220d (OM651 diesel engine) with 5900 km (3600 miles) whenever I cold start or move forward there is black smoke coming from the exhaust, I rarely drive it and just start it for a few minutes once a month. My Toyota on the other hand has 86000 Km(53000 miles) and there is no black smoke from the exhaust till date.
Please Help
Please do not compare perfectly made Toyotas with endless money pit Mercedes benzes.now black means it's running too rich you got a problem with your fuel injection system on that diesel it is very complex all electronically controlled but you say you don't drive it much so take it on the highway drive it for a couple hours go on the speed limit if it's 75 or 75 sometimes that can clean them out and it will stop smoking
