Engine Warning Light Came on

[Sinnedmal]

Hi Gurus,

 

I am driving a W204 anyone have the similar issue like mine.

 

Have reset the warning light 2 times for past 1 month (1st time reset lasted 2 weeks and second time reset was about  2 days).

 

Now after few hours it came back.

 

All initiated when engine was at idle and fail message was lean fuel mixture at idle.

 

Before that happen have changed spark plug and engine filter.

 

Technician ask me to monitor situation but I do not have any problem with performance of engine or fuel.

 

Please advise.

 

Thank-you.

[arkaneslayer]

O2 sensor? Mine was due to an O2 sensor issue.

[jtang]

The mechanic should be able to read the error code with the Merc diagnostic tool. What was the fault shown?

[jon]

Engine warning light on can be anything...

 

Mine came up 2 weeks ago after my Christmas vacation.  Send to Optima Werk and found out that my intercooler pipe crack and air leaking out.

Replaced a section of the pipe which was cracked and now car back to normal.  Price wise, too cheap to believe... was expecting something very ex..

 

Like what jtang said, the mechanic should be able to diagnose the fault... otherwise....

[Sinnedmal]

The error code was lean fuel/oil mixture at idle speed.

If it is O2 how much is the damage

[level z]

i feel it is more of throttle/idle valve issue then o2 sensor(i may be wrong .. )... Maybe a cleaning of the idle vale may help.

 

i changed my throttle before for preventive maintenance ... cost about $500.00 for part only.

[Sinnedmal]

Thanks for info but my ride left 2 years so don't know whether to change or not. But you maybe right

[level z]

Thanks for info but my ride left 2 years so don't know whether to change or not. But you maybe right

 Mine also left about 2 years when i changed the Throttle body.

 

Good luck and hope you solve it.