CLK55 W209 Ground points

[Bazfaldo]

Hi All,

I have been cleaning up my ground wire connectors as part of general maintenance. I have replaced the main battery ground cable and the cable that connects the chassis to the steering pump.

I see there are some other ground cables that bolt onto the inner wings and by the fuse box. I have cleaned all those connectors.

My question is are there any others I can clean?. I have read that there is a main braided ground cable that connects the engine/gearbox bell housing to the chassis on a lot of other Mercs? but when I ordered the battery ground cable and steering pump ground cable from MB main dealer, the parts guys said there wasn't one on my vehicle CLK55 W209 shown in the EPC or wasn't applicable. When I asked him to check ground cables in the EPC I could clearly see a pic of what looked like a main braided ground cable but was greyed out for my vehicle and not applicable?

Can someone confirm if this is true or not. I can't see that the thin power steering pump ground is enough and the only one connected to the engine??

If anyone knows I would greatly appreciate

All the best

 

[sjmaxwell]

On my W208 there were ground points under the front footwell carpets for the memory seats but got to ask why you are replacing them on your W209?

 

[Bazfaldo]

I have a slight misfire, replaced plugs and all HT leads, cylinder 1 and 2 plugs still look fuel fouled, injectors have been sent off to injectortune and have been fully refurbished and sent back with a clean bill of health all balanced. I have been advised my fuel rail pressure is correct approx 50psi. I bought two new coil packs about to fit today, just want to make sure my engine is fully grounded. When the plugs are all clean and Fuel trims reset the car goes very well but after a few runs and when the car gets up to temp the long term fuel trims start to go minus IE to much fuel and the car doesn't feel as powerful low down. When checking the plugs Cylinders 1 & 2 look fuel fouled and bank 1 LTFT -5, slight sooty exhaust tips.

 

[Ted]

Whether it has one or not, it won't hurt to run one from the block to a good point on the body.

 

[Bazfaldo]

Hi sjmaxwell, would love to know what your long term fuel trims are on your CLK55 both banks as a matter of interest/comparison. are you able to check with an OBD2 reader?

 

[sjmaxwell]

Hi sjmaxwell, would love to know what your long term fuel trims are on your CLK55 both banks as a matter of interest/comparison. are you able to check with an OBD2 reader?

Sorry mate away today and at TV4 tomorrow with another car, besides, not sure my reader does that!

 

[Bazfaldo]

OK thanks anyway, most basic OBD2 readers will show this info. If there are any other CLK55 W209 owners on this forum would love to know your long term fuel trims on both banks, just to compare. Mine are slightly negative, i have never seen positive on my car. I have no vacuum leaks just seems to run ever so lightly rich. I have -5 bank 1 and -1 bank 2. And I have just replaced both upstream O2 sensors and MAF with genuine MB Bosch so readings should be pretty correct and accurate.