C220 Cdi W203 2003

[Greensquare]

Hi All

I am having trouble getting my Mercedes to Start, it started getting hard to start and took longer and longer turning over before it would eventually fire up, when driving it was getting really smokey from the exhaust when you put your foot down ( Dark Grey in colour) then the starting motor packed up, had that changed along with number 4 injector as this had failed and was causing the starting issues or so i thought. Since i did the work the car has started 4 times and ran really well and no smoke but now won't start at all, i have checked the leak off on the injectors when cranking the car and they seem ok with minimal fuel coming out of them. It does not have the fuel pump in the tank on this model and the only thing i can notice when trying to find the fault is low pressure fuel going to number 4 from the fuel rail, when i loosen the nuts on the rest of injector feed lines fuel squirts out ok. Does anyone have any suggestions on how i can fix this problem ?
The car has covered 135000 miles and has full service history, it too good to scrap !!

 

[mersum1es]

Can you see air bubbles in clear return lines, o-rings changed (they harden over the age)?

You mean you get no fuel out from #4 high pressure feed line, but others 3 are delivering good amount? Sounds very odd.

Said car was running well after repair, I assume your were lucky and leaky injector didn't break the piston yet - tried to compression test anyway?

(When someone comes and sugget glow plugs - its not that.)

 

[Greensquare]

I can see air bubbles going back into the fuel filter, do you know what would cause this ?

 

[mersum1es]

Air leak in britlle hose/ o-rings

 

[Greensquare]

is that by the fuel filter? sorry to sound stupid but there are as you know many fuel lines can you be more specific, i really appreciate your help in this matter as i have been searching the forum for solutions for days.

 

[mersum1es]

All return lines do brittle over the age, and those lines are sealed in both ends by o-rings which harden (you can try chage them only at first place) and start drawing air in

W202 diagram shows all lines between pumps https://www.ilcats.ru/mercedes/?fun...2&group=07&subgroup=122&imageNo=1&language=en

W203 diagram is different around fuel filter https://www.ilcats.ru/mercedes/?fun...2&group=07&subgroup=122&imageNo=2&language=en

and you wont have that shut down valve which is shown left of the hp pump...

 

[Greensquare]

Excellent, thanks for your help, i will order some o rings and let you know how i get on.