Merc A150 engine hard to star, sometimes

[Carl christoffer bruenech]

Hello im new here, but already love this forum!
Perhaps someone has got a tip for me?
We recently acquired a 2008, A150 with 175.000 km on tacho- all services followed

Engine will not always start instantly- sometimes it does, like it should, but recently quite often it is just cranking and not firing up- just got to stop for a little while and try over, and then its suddenly on- engine sounds «dry»- so I took of air filter and sprayed some fuel mist in the intake and this had an effect. I couldnt pump as much fuel mist (fuel on a spraycan) as the motor really wanted.. so it stopped before it really got going

however, this pointed me in the «short on fuel direction...»
Fuel pump and filter I understand is in the tank (?) - since this problem doesnt really follow a pattern-
What do you think could be the cause? Injectors, filters, relay, sensor... I dont know - ive not read out any error codes yet... thanks for any clues

 

[ajlsl600]

Is it cranking fast enough. Get the batt checked over.
Sometimes the crank sensor does not see, let's say 900 rpm and therefore the ecm does not open the fuel valve. On occasions I have "snuffed" such motors and that has brought up the cranking speed to within limits resulting in a start. A replacement battery has resolved the issue. This is just an example I don't say this is yr issue. How is it if jump started from a Good batt on a running car? If you try this Follow the instructions in yr owners manual ref jump start.

 

[Carl christoffer bruenech]

Is it cranking fast enough. Get the batt checked over.
Sometimes the crank sensor does not see, let's say 900 rpm and therefore the ecm does not open the fuel valve. On occasions I have "snuffed" such motors and that has brought up the cranking speed to within limits resulting in a start. A replacement battery has resolved the issue. This is just an example I don't say this is yr issue. How is it if jump started from a Good batt on a running car? If you try this Follow the instructions in yr owners manual ref jump start.

 

[Carl christoffer bruenech]

Thanks alot!! Its cranking fast, as normal- new battery fully charged - 12.8 v
Its line every 3 times I try to start, wether is has been left alone for 4 days or 4 minutes.. difficult to pin down

 

[ajlsl600]

See if any fault codes logged. Go from there.

 

[Carl christoffer bruenech]

I agree!! Will do

thanks

 

[Carl christoffer bruenech]

Hm... the engine suddenly dies while driving- motor sticks - and starter will crank the engine at all.... wonder if the timing chain just broke.....

 

[ernieh]

Hm... the engine suddenly dies while driving- motor sticks - and starter will crank the engine at all.... wonder if the timing chain just broke.....

Wonder if the difficult starting was due the chain having slipped a couple of teeth and now has broken completely. If this is the Renault engine, don't they have a reputation for self-destruction? Maybe somebody can help there!

Ernie

 

[mattkh]

Hm... the engine suddenly dies while driving- motor sticks - and starter will crank the engine at all.... wonder if the timing chain just broke.....

Has the serpentine belt got stuck in the pulleys?