Juddery Acceleration (Engine Warm), No Codes.

[CrustyClam]

Hi,

After some advice please. It's only happened once, but if it has I'm sure it's the beginning of something.

I got a real hesitation and judder (from standstill) when I put my foot to the floor. The engine was at a good temperature. The car is running great apart from this one instance. I have checked codes, nothing shows.

On my return journey I had the MB2 recording all the freeze frames. Fuel trims are good (that's good since the manifold and a leaking rocker cover have been replaced).

Googling it could be a coil on its way out. (I have a spare one in case, but not much use changing now as symptom has only occurred once)

I'm going to keep recording decent journey lengths which may give me the opportunity to capture useful freeze frames, and highlight an issue.


Any suggestions?

Thanks

 

[bembo449]

Foot to the floor ??

 

[CrustyClam]

Foot to the floor ??

Yes, at a roundabout and needed to shift. (And it didn't....close)

 

[Uncle Benz]

Presuming this is w164 ML? Not accompanied by a noise like a machine gun?

 

[CrustyClam]

Presuming this is w164 ML? Not accompanied by a noise like a machine gun?

It is a W164. No untoward noises (at least not that I heard)

 

[GordonR]

Transmission oil and filter change?

 

[CrustyClam]

Transmission oil and filter change?

Yes, had that done.

 

[CrustyClam]

Just to add:

Spark plugs have done about 12k, replaced 30 months ago
Engine and transmission mounts replaced.
Air filters look clean, done about 12k, replaced 30 months ago.
Intake manifold replaced a few months ago, and a rocker cover also.
Fuel filter has not been replaced (15 years I believe is the point it should be done, I stand to be corrected on that. But I have been told prob will still be ok)
I have always run on v power.

 

[Uncle Benz]

Fair dues. I’ve changed quite a few hyvo chains in w164 transfer gearboxes. They jump the cogs hoofing from standstill. Progress is juddery, but with a machine gun soundtrack. Just a curveball thought.

 

[CrustyClam]

Fair dues. I’ve changed quite a few hyvo chains in w164 transfer gearboxes. They jump the cogs hoofing from standstill. Progress is juddery, but with a machine gun soundtrack. Just a curveball thought.

This is why forums like this are useful. Never heard of this, but I have a good memory for hints and tips from other posts. This may be useful for others.

 

[Uncle Benz]

I did a write up long ago, but after the upgrade a lot of stuff is hard to find.

You can test for it easy, find a slight uphill, standing start and give if hard throttle. Have the window open and you can’t miss it! It’s worse with a trailer on

 

[Blobcat]

I did a write up long ago, but after the upgrade a lot of stuff is hard to find.

You can test for it easy, find a slight uphill, standing start and give if hard throttle. Have the window open and you can’t miss it! It’s worse with a trailer on

Here’s a thread on it

 

[Uncle Benz]

Cheers ears!