Fault Code : P1664

First check connections to see if any corrosion . Then use a code reader see what all codes pull up (write down) then clear them out and see what happens .

black smoke is over fueling and although the turbo appears to spin ok the vale variation actuator may not be operating correctly
there are vanes in the exhaust turbine housing that are altered to increase the exhaust gas flow onto the turbine blades for quicker acceleration and these vanes are operated by a vacuum actuator and rod by a sensor
the vanes are subject to extreme heat and can rust stuck open or the hose gets hard and cracks
s not allowing the vanes to work
I would be concentrating in this area before the EGR valve
run the fault codes as well to get a better idea of the possible fault as some systems only put the light on for extreme conditions in engine and transmission

the cause of the heavy black smoke is un-burnt fuel. is from excessive fuel pressure, faulty injectors,ignition timing out. If it is a turbo operation then the turbo is not producing the correct boost for the fuel settings . Check turbo for vane actuation . low power comes from overfuelling, low air flow. run the fault codes to see which sensors are out of parameter.

check for correct turbo operation
run the fault codes

Fault code P1664 is the Electric Heater Open current and stored.It is a most common fault on these models. If you will try to find it is in the engine compartment by the engine block above the starter motor. As I remember are not repairable and you have to change it. I personally suggest ask a qualified technician to do the job for you.Ask and how much is the cost.

Hi....... sorry my friend you need to code keys and delete the originals,,,,, you need to attend dealer and put vehicle on Star Diagnosis..... no other option.... could also be fault with nthe infra red ignition.... stillneed to get vehicle on star diagnosis.... dont use others.... they can corrupt your vehicles computors..... Hope this helps..... Steve.

hi, unfortunately this is one of them how longs a piece of string things, you could purchase a code reader reset the error code but, what you have to think of is what caused it to do it in the first place, accelerating to hard should not cause an error ( i do it all the time in my car lol ) but it might be related to the 02 sensor getting to much unburnt fuel passing it which would cause the engine light to come on, though if the car is running as normal i doubt that will be the issue, i would myself on a car like that take it to the main dealer and get them to check it out, as buying an inexpensive code reader might not cut the mustard with this one, and parts being as dear as they are for merc's i would play on the safe side, spend a few bucks to save a load...sorry not much help

May I know the full chassis no : like WD_203xxxxxxxxxxx.

hello,according to service information;smoke formation or si 07.16-p-0004a (service inform) from mb ,your engine have normal function,if you want ,ask your dealer about the service inform with number 07.16-p-0004a,you can read the explanation regarding your problem,ty

fit new fuel filter