2007 Bluetec. Rough Idle Hard start
Thread Starter
Junior Member
Joined: Mar 2015
Posts: 25
Likes: 2
2007 E320 W211 Bluetec
2007 Bluetec. Rough Idle Hard start
I have a 2007 Bluetec that started to have problems with a rough idle. It has progressively gotten worse and now I am having a hard time staring. When you do get it started if you give it some time it will start to run normally. I have changed the fuel filter.
I am looking for s ome guidance now sure what to do with this.
Car has about 225k miles on it.
It is not a daily driver. I only use it when I need to pull the trailer or want to drive a nice clean car. not like my beater VW TDI that I never clean.
I am looking for s ome guidance now sure what to do with this.
Car has about 225k miles on it.
It is not a daily driver. I only use it when I need to pull the trailer or want to drive a nice clean car. not like my beater VW TDI that I never clean.
Senior Member
Joined: Jan 2013
Posts: 305
Likes: 42
W211 E320 Diesel OM642
If you have no access to star diagnostics to see how injectors are performing, a quick way of assessment is by checking for how much fuel each injector returns after 10 seconds of cranking.
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Newbie
Joined: Dec 2019
Posts: 10
Likes: 6
From: York. England.
W204 2.1D
225K miles will have taken its toll on these injectors. Chances are good that only a very few of the nozzle spray holes are injecting any fuel, usually exacerbated by infrequent fuel filter changes and crappy fuel.
Removing these injector nozzles from the end of the injector is quite straight forward with due care and attention.
My W204 has 212K on the clock and I've just done mine. The nozzle on cylinder 1 had 4 out of the 7 spray holes blocked when I pushed some carb cleaner through. No.2 injector would only spray out of 1 hole! 3&4 weren't much better.
20 mins in the Ultrasonic cleaner in a neat solution of oven cleaner and all 7 sprayholes were back doing their job.
Takes a few cranks to get the fuel bled through after reassembly but that's normal.
When the engine does fire up, you'll probably find the idle speed to be uncharacteristically high for half a minute or so. The ECU still thinks it needs excessive fuel trim to compensate for blocked injectors and recalculates the new true value over time, which also serves as confirmation of your findings and fixings.
Instant starting and no more lumpy running when cold. Result.
Removing these injector nozzles from the end of the injector is quite straight forward with due care and attention.
My W204 has 212K on the clock and I've just done mine. The nozzle on cylinder 1 had 4 out of the 7 spray holes blocked when I pushed some carb cleaner through. No.2 injector would only spray out of 1 hole! 3&4 weren't much better.
20 mins in the Ultrasonic cleaner in a neat solution of oven cleaner and all 7 sprayholes were back doing their job.
Takes a few cranks to get the fuel bled through after reassembly but that's normal.
When the engine does fire up, you'll probably find the idle speed to be uncharacteristically high for half a minute or so. The ECU still thinks it needs excessive fuel trim to compensate for blocked injectors and recalculates the new true value over time, which also serves as confirmation of your findings and fixings.
Instant starting and no more lumpy running when cold. Result.
Last edited by Fast n Furious; Oct 12, 2022 at 04:59 PM. Reason: duplication
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Senior Member
Joined: Jan 2013
Posts: 305
Likes: 42
W211 E320 Diesel OM642
I noticed that if the injector is not spraying right, glow plug will have small residue cover over the tip. There should be nothing on the surface of the glow plug's tip. That's my fast way of confirming injector failure.
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From: New Hampsha
'17 GLS450, '14 GLK250, Grandpa's Roadster
Thread Starter
Junior Member
Joined: Mar 2015
Posts: 25
Likes: 2
2007 E320 W211 Bluetec
I have let the car sit over the winter and tended the battery. I am taking a trip in April and I want to get this fixed so I can take the car.
At present, the car won't start. It starts to try to start but doesn't.
I now have the computer I can hook to the car.
Things I suspect are:
Injectors,
Timing chains
crank sensor
At present, the car won't start. It starts to try to start but doesn't.
I now have the computer I can hook to the car.
Things I suspect are:
Injectors,
Timing chains
crank sensor
Member
Joined: Oct 2011
Posts: 105
Likes: 39
From: SC
2015 GL350, 2013 GL350, 2002 ML320, 1983 E300TD-D
I have a 2007 Bluetec that started to have problems with a rough idle. It has progressively gotten worse and now I am having a hard time staring. When you do get it started if you give it some time it will start to run normally. I have changed the fuel filter.
I am looking for s ome guidance now sure what to do with this.
Car has about 225k miles on it.
It is not a daily driver. I only use it when I need to pull the trailer or want to drive a nice clean car. not like my beater VW TDI that I never clean.
I am looking for s ome guidance now sure what to do with this.
Car has about 225k miles on it.
It is not a daily driver. I only use it when I need to pull the trailer or want to drive a nice clean car. not like my beater VW TDI that I never clean.
Thread Starter
Junior Member
Joined: Mar 2015
Posts: 25
Likes: 2
2007 E320 W211 Bluetec
I am going to try to pull the injectors today. I will probably need a slide hammer
It smokes pretty bad but does not start.
I did use some starting fluid and was able to keep it running if I gave it little squirts.
Code are all over. Rail pressure high, rail pressure low.
I am not sure how to read injector flow on the computer.
It smokes pretty bad but does not start.
I did use some starting fluid and was able to keep it running if I gave it little squirts.
Code are all over. Rail pressure high, rail pressure low.
I am not sure how to read injector flow on the computer.
