logo
Welcome Guest! To enable all features please Login or Register.

Notification

Icon
Error

Options
Go to last post Go to first unread
Offline travelvietnam  
#1 Posted : Monday, July 19, 2010 3:51:27 AM(UTC)
travelvietnam

Rank: Advanced Member

Reputation:

Groups: Registered
Joined: 3/28/2010(UTC)
Posts: 48

Hi, I am called out to a 2003 Mercedes Benz C220 CDi, 203 chassis.
Customer reports poor starting whether engine hot or cold. It seems better when cold but will crank over for 5 - 6 seconds before starting. He used the car yesterday and every time he turned it off it would not start. He says he could only start it by releasing the pressure to the injectors by slackening the supply pipes, then cranking the engine over which eventually starts.
I connected up the launch X431 which returned no fault codes.
Looking at live data, the fuel rail pressure 1 is 0 bar engine off, crank the engine over and the pressure rises slowly over 5 seconds till it reaches 120 bar, then the engine will start and run along quite merrily. No loss of power, good fuel consumption etc. Turn the engine off and the pressure drops to 0. I have a Mercedes Benz Vito with the same 2.2 CDI engine, when I checked my fuel pressure it was reading 240 bar engine off, rising to 340 bar engine running .
Removed the rear seat to check the low pressure pump, the multi plug has 5 wires, 3 thin wires for the level sensor and 2 thicker wires for the pump......but there is no actual pump in the housing if this makes sense....its just a level sensor but the wires are there for a pump.
I can’t see any air bubbles in the clear fuel lines around the rail.
I’m thinking the fuel pressure regulator not allowing the pressure to rise due the neoprene seal? But not being a diesel, I’m looking for reassurance that it could be this regulator.
Hope you can help?
Sponsor
Do you have a question about AutoHex? Chat with us now

Check our Autohex scan tool
Offline werner  
#2 Posted : Monday, July 19, 2010 4:31:11 PM(UTC)
werner

Rank: Advanced Member

Reputation:

Groups: Registered
Joined: 3/28/2010(UTC)
Posts: 41

The low pressure pump is on the engine.
Most likely cause of problem is the seal on the pressure regulator of the rail. This is a common problem and the 2 piece seal kit costs small money. I'd change this first and if you don't get a result, check the injector leak off/returns.
Offline travelvietnam  
#3 Posted : Tuesday, July 20, 2010 1:31:08 AM(UTC)
travelvietnam

Rank: Advanced Member

Reputation:

Groups: Registered
Joined: 3/28/2010(UTC)
Posts: 48

Thanks for that. I’ll get some regulator seals tomorrow.
To check the injectors, do I remove the leak off pipes and make sure the same amount of fuel comes from each injector? If I’m correct, if one has more coming from it than the others then that injectors is faulty?
Offline whiteRabbit  
#4 Posted : Tuesday, July 20, 2010 4:11:05 PM(UTC)
whiteRabbit

Rank: Advanced Member

Reputation:

Groups: Registered
Joined: 3/29/2010(UTC)
Posts: 42

I agree with him. There are two small seals in the regulator (very cheap) which split. You may have been lucky as most leave this until it’s a NON starter.
I have posted about this on Sprinters (?) Use the search button using CDI should work.
Offline travelvietnam  
#5 Posted : Wednesday, July 21, 2010 3:17:05 AM(UTC)
travelvietnam

Rank: Advanced Member

Reputation:

Groups: Registered
Joined: 3/28/2010(UTC)
Posts: 48

Hi,
Eventually got back to this car yesterday and replaced the two small seals onto the pressure regulator.
When I removed the regulator, I found a very small amount of what looks like very thin plastic, covering the end of the regulator. I checked there wasn’t any left in the fuel rail before fitting the repaired regulator.
Starting the car was quick and easy, but looking at the pressure on the Launch, the pressures still drop to zero when the engine is switched off, and takes a second or two to build up before the car will start again.
The pressure is leaking out from somewhere, maybe a dribbling injector? Or faulty non return valve in the pump?
Looks like this may be a job for a diesel specialist unless anyone can advise further.
Thanks.
Rss Feed  Atom Feed
Users browsing this topic
Guest
Forum Jump  
You cannot post new topics in this forum.
You cannot reply to topics in this forum.
You cannot delete your posts in this forum.
You cannot edit your posts in this forum.
You cannot create polls in this forum.
You cannot vote in polls in this forum.

Powered by YAF 2.1.0 | YAF © 2003-2014, Yet Another Forum.NET
This page was generated in 6.683 seconds.