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Engine Hard Start Warm? Injector Issues?

 
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amishorty



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2004 Volkswagen Passat
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Post01-04-2017, 13:00    Subject: Engine Hard Start Warm? Injector Issues? Quote

Hello everyone,

Here are the details:
Passat 3BG/3B6, sales type, 2.5 TDI 4motion, year 2004, mileage 403,000 km.
132 kW, engine code BDH, 6-speed manual transmission.

I had the injectors replaced in my Passat. With the old injectors, it would always start, no matter the outside temperature, but the performance was very poor.
Now he has the revised ones installed, and the performance is as it should be.
Unfortunately, it only starts after about 3 seconds when it's lukewarm, and it emits white smoke.
Diesel fuel is not completely combusted.
Now I've taken the nozzles out and examined them closely.
I've noticed that the CU rings aren't sealing properly; specifically, the conical part that should be in contact with the nozzle is not actually making contact with the nozzle's cone, but instead rests on the threaded nut of the nozzle body. This means the sealing ring isn't centered, and soot accumulates between the nozzle and the cone.
Also, the installation depth of the nozzle is likely no longer correct, which is very important for achieving optimal combustion.

I took some pictures, which I'll upload here soon.
Has anyone ever seen anything like this before?

Your opinion on this is important to me, because I don't want to reinstall the nozzles like this.
I've never disassembled a nozzle before, so I'm hesitant to remove the nozzle holder nut.
It might be simpler than it looks, but Rainer had already written to me about this topic and talked about "nonsense." This "nonsense" probably arose during the revision, because before, the fuel injection quantity comparison was in the "+" column, and afterwards it was in the "-".
However, the damage wasn't caused by me, but by the Bosch service that refurbished the injectors. I only removed and installed them.
They have now been driven for approximately 8000 km.
When the engine is warm, it starts perfectly and runs very smoothly. It has full power, and the fuel consumption is between 5.8 and 8.0 liters per 100km.

Thank you for reading.
HG
Michi.


Translated on 23-09-2026, 13:56.
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Post01-04-2017, 16:41    Subject: Engine Hard Start Warm? Injector Issues? Quote

Quote:
... does not rest on the cone of the nozzle, but on the threaded nut of the nozzle body.
... because previously, the fuel injection quantity comparison was displayed with a "+" sign, and afterwards, it was displayed with a "-".

Unfortunately, two completely useless statements... icon_question.gif
Why are the values of the idle speed control not being posted if they cannot be interpreted?


Translated on 23-09-2026, 14:00.
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POR1



Joined: 03/11/2017
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Post01-04-2017, 22:49    Subject: Engine Hard Start Warm? Injector Issues? Quote

Hello Michi,

Sure, here's the translation:

"Images would be helpful here!"
I've disassembled and successfully reassembled several injectors before. It's not rocket science.

Regards,
SK


Translated on 23-09-2026, 14:00.
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