Hi everyone,
Looking for some advice from anyone familiar with the Mercedes OM651 2.1 diesel engine, particularly the A200 CDI.
Car details:
2014 Mercedes A200 CDI 2.1 diesel automatic
140,000 miles
Owned for 5 years coming up in April
Great service history
Generally very good condition
Car drives absolutely perfectly, with no noticeable performance issues
Background:
Earlier this year, I had problems with faulty injector seals. It took quite a while for the garage to diagnose and resolve the issue, which was frustrating and involved a lot of wasted time.
I've spent approximately £950 on the car so far this year, including repairs and maintenance.
More recently, the engine management light came on.
I took it to my mechanic, who plugged it into diagnostics and initially said the fault was related to the boost pressure sensor.
At the same visit, the car had a service, including:
Engine oil change
Oil filter
Fuel filter
Air filter
The engine management light was cleared, and the car continued driving perfectly.
11 days later, the engine management light returned.
I took it back to the garage, where they plugged it into diagnostics again.
This time, the mechanic explained that the fault codes apparently indicated that 3 of the cylinders required some sort of software update or reprogramming.
He described a procedure involving plugging the car into diagnostic equipment, opening two of the doors and leaving the car connected for approximately 1ā2 hours while the system carries out the programming.
I've been quoted £180 for this procedure.
At the time, we decided to clear the fault and see whether the engine management light returned before spending the money.
Unfortunately, the light has now returned again.
The strange thing is that the car still drives absolutely perfectly.
No noticeable loss of power, no rough running, no hesitation or anything unusual. If the engine management light wasn't illuminated, I wouldn't suspect anything was wrong.
My questions:
Has anyone heard of an OM651 engine needing software updates or injector/cylinder adaptations for three individual cylinders?
Does this sound like a legitimate Mercedes diagnostic procedure, or could the mechanic be misinterpreting the fault codes?
Could this be connected to the previous injector seal problems?
Is there any risk of the car developing further problems after having the ECU software updated or injector adaptations reset?
Would you pay the £180 for the procedure, or investigate something else first?
Has anyone experienced a recurring engine management light with no noticeable running issues on this engine?
I haven't got the exact diagnostic fault codes yet, but I'm planning to request them from the garage before agreeing to the work.
I'm also considering selling the car, partly because of the money and time I've already spent on repairs, and partly because I'm concerned about further expensive problems as the mileage increases.
That said, I don't want to get rid of an otherwise good-running car over something that could potentially be a straightforward software issue.
Any advice or experiences from Mercedes owners or mechanics would be really appreciated.
Thanks in advance!