darkm4n

Update: After further investigations and 1000km I did not see any metal in the oil. Maybe it was contaminated before or the mechanic didn't actually see it. Thing I did during this time: 1. Replaced the camshaft position sensor, the engine runs smoother, not a big difference but it is. 2. Replaced the camshaft solenoid, big change, the car runs a lot better, much less engine stuttering when stopping or starting from a standstill. 3. Replaced the battery with the correct 60Ah ( it had a 55Ah in ) AGM, starts and idle better after this. The most significant improvement was after I replaced the camshaft solenoid. There is still some stuttering left but it can be easily ignored, or maybe this is the way the DCT works. Another question: do your 0.9 DCT shows a dim in the cabin lights when throttling in neutral ? Gearbox in N, push the throttle half way, fast. Do the light inside the vehicle loose intensity for a split second ? I suspect a charging regulator/alternator problem somewhere that could also be linked to the engine stuttering when stopping as the gearbox is electric and the load increases when the clutch engage/dissingage. It's clear the voltage drops and the alternator kicks in, for example on STAR I did see a 800w steady alternator rate on idle, going to 1600w when throttling. Thanks!

Unfortunately not, and I would prefer to get the engine done instead of buying a used engine that may have the same problems. In most situations you cannot start the engine.

For sure advertising here is different. Back to the topic, I believe I have to find out what an engine rebuild involves and what are the common parts that needs changing. Probably we are talking about rings, machining the head and checking the crankshaft bearings ( don't exactly know the term for this ). I couldn't find anyone that did a 453 rebuild.

Yes Chopper, indeed but at least they advertised it like so. Any non technical person going to buy one would never suspect it's actually a Twingo with different body panels. And probably also never suspect reliability issues from a Mercedes "licensed" ( as advertised ) car.

Thanks to everyone for their input! Really appreciate your advice. It's such a shame on Mercedes they build and sell such a cars... the problem it that you cannot find any information on a quick search about the flaws of the new 453, at least not easily find them. Or let's say for an average customer, you cannot find anything that worries you about the car. I really consider a 70k km car "new" compared to the average milage a BMW / Mercedes or any other similar brands can take without problems, at least without major engine failure scenarios. I documented myself about how Smart adapted the engine and tilted it to 30 degrees, modifying its oil lubrication system to match the new configuration. I may be wrong as I didn't find too much documentation but for sure you cannot compare the Dacia engine setup with the Smart implementation, there are major differences. I'am still searching for a 453 owner that has the same engine for their general impression about the car, this model clearly has a problem just I want to see more input from other persons that had the same failures.

That's weird, I never heard such thing. This motor is used in a lot of cars and I couldn't find any complains about. Also, it is used in Dacia Logan, a local car that most cab drivers use in Romania and all of them really drive them a lot without any issues. I may be wrong, of course. Currently situation sustains what you are saying.

Hi, I recently bought a used Smart ForFour 0.9 DCT 90HP, 2016 year, 70000 km and I have some concerns regarding this car, I would like to know if anyone else share the same experience I got. I will try to describe the facts that worry me the most: 1. High fuel consumption, the car takes about 16 l/100km, that about 14.5 mpg, in ECO mode and really normal city driving, no WOT or abusing the car in any way. 2. When it start cold, between 3 and 8 degree C outside, the idle slowly fluctuates between 700rpm and 1800rpm. It does that for about 1 minute, mostly depending on the outside temperature. Also it takes about 2.. 3 seconds cranking time till the engine starts. 3. On the last maintenance, the mechanic notices that the oil was contaminated with metal. There wasn't any big metal chunks, just very fine metal particles, enough of them to change the oil color to be a more gold color looking let's say. 4. I changed the spark plugs, absolutely no change after this, the old sparks looked very good, no lean or rich coloring. 5. Most of the times, when I break slowly coming to a stop, the engine shakes and vibrates pretty hard, there are times when it is about to stall. This happens till the clutch is fully open and something also happens when the car starts to move. What worries me most is the oil contamination and the low fuel economy, I am curious if anyone else experienced such problems. I put the car on Xentry and there are no codes. Thanks!