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+1 on the above posts!
Diesels Don’t like air in the fuel system.
Get those leaks fixed ASAP then go from there if you still have the problem.outside of changing fuel and air filter perhaps the turbo is worn ( any excessive ” whine” from the turbo ? )
Quoted From 619DioFan:
outside of changing fuel and air filter perhaps the turbo is worn ( any excessive ” whine” from the turbo ? )
That was my first thought as well. Is the exhaust in good shape? Obviously if there are leaks on the exhaust gas supply line, the turbo won’t be able to spool up.
Does that diesel have a boost gage on the cluster?
I definitely agree with every ones suggestions.
Keep us posted.
Turbo appears to be working properly – I have hard pull at high RPM – only a problem in low RPM (below 2000). Fixing that dead injector helped – the car picks up better, but not great. I listen to the injectors and 2 / 6 injectors sounds different. Either 2 injectors aren’t spraying properly or 4 are not spaying properly. The spraying sound is inconsistent. Also did not see leak in exhaust system – exhaust condition is excellent.
I found that this specific car has problem of carbon building up at glow plug holes and if this build up gets excessive, not all the cylinders get warmed up by the glow plugs. So even with the working fuel injectors, the car smokes (a lot) at start up. This is why I am taking out entire intake system next week. Is pain in the butt, looks like 6mm hex aluminum bolts all around the intake manifold. I am going to take out each glow plug and clean the hole with the reaming tool. Then install new set of glow plugs, but the injection pump is also buried under intake manifold so it is also a good time to address that injector pump leak. I ordered the parts last week and still waiting for the tools:
http://mercedessource.com/node/9341
http://mercedessource.com/node/2615
http://mercedessource.com/node/9616Originally I was just going to replace that dead injector and do diesel purge. But looks like this is going to get complicated.
Sounds like your’re on the right path. Keep this thread updated if you don’t mind, i’d like to see where it goes.
First that car never had a lot of power to begin with because of it’s weight and relatively small engine size but there are a couple of things that I’d like to add to the discussion if I may.
The first is timing. I know this is a diesel and that it doesn’t have an ignition system to time but the fuel distributor is something that gets timed and if it’s off the engine will perform poorly so you might want to check the timing on the fuel system.
Second, an exhaust restriction especially on a turbo car can cause all kinds of issues as the exhaust will not be able to cleanly exit the vehicle and as a result won’t spin the turbo up and also rob the engine of power.
Third, do a compression check, you’ve mentioned more than once about a lot of smoke that’s being created this could be the result of worn rings which will cause low compression which will also translate to performance problems.
Lastly it could be something to do with the turbo ‘system’ meaning that the waste gate or something like that could be at issue not allowing full boost to happen so be sure to check the linkage on that to make sure it’s working properly. In addition the turbo itself could be worn out causing the excessive smoke as well as the lack of power, an easy way to check this is to expose the turbine and try and move the shaft up and down by hand, there should be NO play, if there is then this would indicate the turbo is worn out and needs to be rebuilt or replaced.
I did the diesel purge over the weekend and retested. 0-20 in about 13 seconds. Shaved two seconds off of acceleration time but still too slow. startup smoking is also better and engine idles smoother. Took out the intake manifold and fount some traces of engine oil – is this sign of failing turbo?
I was able to get to the leaking injector pump fittings, and planning on fixing the leak this weekend (and replace the glow plugs in same time, they are both located under the intake manifold and difficult to get to)
Do you know what the factory specifications were for that vehicle when it comes to torque and HP?
Usually oil buildup in the intake is a sign of excessive blow-by
You can also grab the turbine wheel of the turbo and see if there is play in the shaft.
Did you check to see if you have issues with your crank case ventilation system?
Again i am not a diesel technician so i really cant help you that much. Sorry.
The standard blow-by test for diesel is to take the oil fill hole off while engine running and see if any oil will shoot up or burn in smoke. When I opened mine, it was fine. After the fuel leak repair, I am going to look at the turbo.
I do not have factory specs, but I did see some people posting the cars acceleration on uTube – looks like the car should do 0 – 60 in about 15 seconds. Slow, but not painfully slow.
Hi guys,
Finally put everything back after taking out the intake manifold to fix the fuel leak and glow plugs. Even less smoking at startup, and now the car does 0 – 20 in 4 seconds, 0 – 60 in 14 seconds. Still slow, but not too bad for a diesel car. It was that fuel leak at the injection pump that fixed the issue – I guess it was adding air to the fuel system.thanks for your help
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