Engine Warning Light After Cold Start

[CharlesWhiteman]

A bit weird this-morning, my 07 220 CDi (W203) tends to turn the engine over a bit slowly on a cold start, but it's always started. This morning it didn't start on the first round and then did on the second but the engine warning light came on and stayed on. I let run a minute or so and then switched off for the reset period and tried again. Started fine but engine light on. Nothing sounded wrong and visual all okay. Did a short trip and later on this morning the engine light stayed off.

 

[John Laidlaw]

Not getting any glow plug warnings then ?

 

[alexanderfoti]

Could be a low voltage related code setting the light, really needs to be plugged in to check though.

 

[Wighty]

A bit weird this-morning, my 07 220 CDi (W203) tends to turn the engine over a bit slowly on a cold start, but it's always started. This morning it didn't start on the first round and then did on the second but the engine warning light came on and stayed on. I let run a minute or so and then switched off for the reset period and tried again. Started fine but engine light on. Nothing sounded wrong and visual all okay. Did a short trip and later on this morning the engine light stayed off.

Maybe start of the cold weather showing up an old battery ? How old is it , there is a date stamped on one of the terminals . A Mercedes Star reading is a first port of call or an icarsoft Merc specific code reader will give more info on the fault .
I wouldn't throw parts at the car without correct diagnosis but if it was me and I thought I had narrowed down a possible faulty part and it's a part that would need changing at some point anyway , and that part cost gets towards what a Star session would cost then I sometimes risk it ( that's my sort of mental flow chart for parts/repairs ).
I bourght an icarsoft reader last year which has payed for itself many times over so far .

 

[CharlesWhiteman]

The battery showed 12.3v this am, so I don't think its a battery issue. I'm leaning towards fuel pressure maybe, as sometimes the engine will stall after starting sometimes.

 

[CharlesWhiteman]

Not getting any glow plug warnings then ?

No. Glow-plugs appear to be correct.

 

[Wighty]

The battery showed 12.3v this am, so I don't think its a battery issue. I'm leaning towards fuel pressure maybe, as sometimes the engine will stall after starting sometimes.

Even more need for a diagnostic (MB specific) code read ?

 

[alexanderfoti]

Probably an air leak in the low pressure side.

 

[CharlesWhiteman]

Even more need for a diagnostic (MB specific) code read ?

I reported it to my (currently) chosen merc indie and nothing came back, but I shall have to ask them to check for error codes.

 

[Westheath]

The battery showed 12.3v this am, so I don't think its a battery issue. I'm leaning towards fuel pressure maybe, as sometimes the engine will stall after starting sometimes.[/QUOTE

Isolate the battery from the vehicle (remove earth lead) leave for 15 mins
check voltage with meter it should be above 12.5v

 

[RUBBER_UNDIES]

My money is on the Battery or crank sensor.

 

[CharlesWhiteman]

It was the battery