limiteddi

Oddly, car takes off completely fine from a stop position but when its rolling slowly and I press the gas pedal its like im pushing a shopping cart before turbo kicks in at about 2k RPM. Prior to this, the engine used to confidently pick up power/speed from the same gear after I exited a corner but now it's barely moving RPM up and then the tranny needs to downshift to pick up power. Is almost never downshifted before. Now it is sometimes very annoying when making left turn because it takes 1-2 seconds longer to clear an intersection if I roll in at low RPM.

Any ideas what could be causing this?

DC-BENZ

Probably Limp Mode "drivability issues". Does turning it off then back on fix it?

jacobsung

Something is definitely wrong. No check engine light on?

limiteddi

Nope, nothing.

jacobsung

OK. No check engine light. There is a turbo lag that we all hate. But my GL350 almost never downshifts. Try to ODBII scan and look for any error code.

DC-BENZ

So does turning it off then back on fix it or is this on going? Also how long has this been going on? When was your last service and how many miles are on your vehicle? (~60k?)

limiteddi

This is a permanent issue, turning on/off doesn't help. 90k km on it, last service about 3 month before. I noticed it about a month ago.

DC-BENZ

Well do the least expensive checks first.
Check both air intake hoses for holes/tears and that they are connected properly
I'm assuming your air filters and fuel filter were changed by the dealer.
Use your deep socket 24mm to remove the exhaust pressure sensor (after you remove the engine cover) check to see if its clogged with gunk. It's right behind the rounded foil close to the firewall in the center.

DC-BENZ

Any update?

Robert Warming

I've got the same problem too and the check engine light is on....

I have a 2010 Mercedes Diesel GL350 SUV and just had the Turbo Charger replaced from an oil leak. Now it is having an accelleration problem. Every now and then it cannot accellerate in the lower gears, but just stays in the higher gears. Then restarting engine it goes back to normal. Even better than normal. It goes over 4000 RPMin every gear. The mechanic doesn't know whats wrong with it and reseted the light and now came back again...
'
The check engine light comes on when this happpens. Thanks, Rob

DC-BENZ

What's the code that shows when it's read?

Also, because there was a leak you needed at new turbo?

Robert Warming

I don't have the scanner so I don't know what is the code. Yes, they told me I needed a new turbo charger and it was leaking oil. They changed it and all the seals that came with the new charger. Then, they resetted the computer but again.. it came back after about 20 miles driving. At first it was the yellow triangle with the exclamation point, then now it is the check engine and wouldn't go away.

Get to noticed at starting the engine seems to fixed the acceleration temporarily, but only for like 10 to 15 miles and will come back again and feels like you are dragging it with the accelerator all the way down...

DC-BENZ

Go to Autozone and ask someone to read the code for you. Let us know what they say.

I had an oil leak coming from 2 red gaskets at the Turbo on my 164ml350, I replaced the gaskets and had no more leaks until the oil cooler leaked.

Also, you should be posting in the x164 forums, this is the x166 forums.

Booggyye

I have the same problem now, any suggestions please?
thanks

hai00

Hi, I have a W212 diesel with 145K mile. It had similar issue with engine light on at 135k. Started out as occasional check engine light, then occasional higher RPM shift than normal. Then it got worse over the months, and shift became jerky, sometime no power. In my case, the issue turned out to be "differential pressure sensor". Faulty exhaust pressure reading seems to make ECU misbehave. I expected Diesel recall AEM warranty to cover it, but it is not. standard OEM part is $90-150. One dealer tried to charge $1200 for a sensor replacement (300 for diagnostic cost) . another charged $450 (california price for you). I was pissed off, and bought the tool to replace it, but then chickened out and got it done at dealer.

By the way, I also got X166 diesel with 92K mile on it. I like the diesel for efficiency n torque, fuel saving may not even cover the higher maintenance cost vs gas engine.