olabru

Hi. Sorry if my language and grammar is not quite correct, but I hope you understand.

My GL 320 -07 model (km=216000) gets an "hickup" when I drive in 65 km/h in 5. gear and in 80 km/h in 6. gear - the rpm on engine is then ca 1400-1500. If I gear down manually, so the rpm goes to ca 2000 it goes away. The "hickup" happens only when the road is level, and throttle is constant (cruice control or manualy gas-use). If the road goes up or down it is ok, and no "hickup".
I have an Launch x431 mini pro - diagnostic item and the only error code is - U010087 - Communication with engine control unit has a malfunction, the message is missing. I delete error but it comes back.
Some times its ok, and sometimes (especially in 60 km/t) its real bad, and I gear down manually to 4. gear.
It seam like an engine issue (around 1400+ rpm), and not an gear issue.
Does anyone been into an simular problem?

Elbeau

I had a similar issue with another, non-Benz, car several years ago and it was due to a misfire in one of the cylinders.

Max Blast

Well it’s a diesel, so this is where you need a live data streaming capable scan tool to see what the injectors are doing. There’s no ignition system to cause any misfire issues it’s all fuel driven.

sounds like a part throttle no pulse issue.

eric_in_sd

The "no communication with the ECU" error kinda seems significant.

I'd start by ensuring that the voltage supply is tip top. Possibly there is enough fluctuation to make the ECU glitch. And thus not triggering the spark plugs injectors. Or the ECU is dying. Alternator, battery, and confirm there is not a voltage drop on the cable from the alternator to the post in the engine compartment; dunno about the OM642 but that is a weakness in the M273.

olabru

I tried a Star diagnose, but the hickup did not come at the time. But it has gone worse, so I will try again with the Star.

olabru

I will check out voltage drop, and spekulate some more.

Rafalkuci

[QUOTE=olabru;8835271]Sprawdzę spadki napięcia i jeszcze trochę poeksperymentuję.[/QUOTE
]

vesiadog

You might get more info on diesel specific sites like Sprinter Vans.
I would recommend doing a complete compression test and bore scope each cylinder. If that looks g.
Have you ran injector cleaning additive? When I ran 7.3 powerstroke I always put a fuel additive in every tank. Top end lubricant is very important for diesels.
It seems to me that many people are buying the MB diesels that are not very up to date on all the headaches like The oil cooler disaster .
Injector video well worth watching

https://youtu.be/O_Y3dM8ZApo?si=zo6aB3WtA6eVHtOr