No complaints but a lurch on cold idle CLK350 M272

[Tinonline]

A few years since I last posted...

MOT's have come and gone. Only a pair of drop links unexpectedly caused a fail this year.

My beloved Lexus LS400 has gone to a new owner and the CLK is the main worker. Currently 70k on the clock. (Year 2007) M272.

Now, on cold when warming up at idle...I get an intermittant rev drop, a stumble, sometimes you think it will stall but it picks up. Once warm/hot the issue stops. Unbelievably there are no definative posts on resolving the issue with certianty.

I've replaced all solenoids with the latest revised part number around 2 years ago. Bank A top one threw a code the other day out of the blue so I'm thinking these are consumable items but since clearing said code (touch wood) nothing has reoccured. I have a non Merc one as a spare I feel tempted to fit. (The engine number is outside the camshaft sprocket problem range).

It's not due anything parts-wise yet and no codes are present. I added some injector cleaner but difference. It's a while ago since I've used MAF cleaner and a dose of Cataclean.

I will replace sparkplugs, coils, airfilter as a proactive maintenance measure.

Any thoughts/ideas/similar experiences most welcome?

 

[Tinonline]

A few years since I last posted...

MOT's have come and gone. Only a pair of drop links unexpectedly caused a fail this year.

My beloved Lexus LS400 has gone to a new owner and the CLK is the main worker. Currently 70k on the clock. (Year 2007) M272.

Now, on cold when warming up at idle...I get an intermittant rev drop, a stumble, sometimes you think it will stall but it picks up. Once warm/hot the issue stops. Unbelievably there are no definative posts on resolving the issue with certianty.

I've replaced all solenoids with the latest revised part number around 2 years ago. Bank A top one threw a code the other day out of the blue so I'm thinking these are consumable items but since clearing said code (touch wood) nothing has reoccured. I have a non Merc one as a spare I feel tempted to fit. (The engine number is outside the camshaft sprocket problem range).

It's not due anything parts-wise yet and no codes are present. I added some injector cleaner but difference. It's a while ago since I've used MAF cleaner and a dose of Cataclean.

I will replace sparkplugs, coils, airfilter as a proactive maintenance measure.

Any thoughts/ideas/similar experiences most welcome?

Hi folks,

Here is an update.

I carried out an oil & filter change which was due.

Set about replacing the spark plugs and opted for Denso Iridium as in my experience and other feedback, they are exceptional. The old ones looked ok if not in prime condition - they were not bad. I also changed the coil on plugs. The ones I pulled were not OEM but I don't know how old they were from the history I have. I put QH units in.

The air filters were changed although they weren't due for another year - there was plenty of debris etc in the airbox so everything got a good clean.

Last task was a few sprays of MAF cleaner onto the MAF element - nothing was dissembled.

The engine is now super smooth with better response. Just in case you think that's the halo effect of putting new stuff in...my wife has reported that the car driving noticibly better and feels great.

The lurch appears to have gone...or at least is a controlled adjustment of revs if there at all. If the lurch does return, I'm replacing solenoid magnet 'A' that threw a code a while ago but hasn't since...just in case its out of tolerance but not throwing a code - if that's possible.

Mileage is coming up for 71k and engine doesn't use any oil.