W163 ML 430 Idle rough loss of power up hill

[Benmez430]

Hi All

I hate to seem like another one of those guys that appear on forums just for help but I can assure you this isn't me! Im a giver!

anyways I have recently bought a ml430 lovely car but one thing is bugging me that i cant seem to crack!

A rough idle, car sits about about 550rpm on tick over but has a rough idle and a popping sound coming from the air intake, so this leads me to believe its a miss fire, I removed the coil pack cables one at a time to try and Isolate the faulty cylinder, i believe it is referred to as cylinder 1 closest to headlights on left side (drivers) and #4 closest the the back of the engine (drivers side) but they seem to work intermittently.

the ml is a little slow up to 3000rpm but runs perfect after that.

FYI 88,000 on the clock

I went ahead a changed all 16 plugs anyways no difference, I changed the MAF sensor with no difference

check the ht leads visually which all looked good.

I am waiting for a Obd 2 to come through in the post tomorrow get some codes.

can anyone shed any light on this? anyone had this problem and fixed it?

there are plenty of threads around the place of this subject but nun of them really conclude.

thanks in advanced

 

[stability]

where did you get the maf sensor from - is it a cheap one

merc ones are 290 odd for a reason because they work.

what are the filters like - clogged ?

they dont really suffer with much else - throttle sensors but a star would confirm this. maf sensor will not show a fault if its only started to break down.