2008 MB GL420 pre-facelift X164 is having power steering and other issues.

[captainreiss]

This is my first post, I have come to the conclusion that I need to bring my issues to a wider community because my local garage (not MB franchise) whilst super enthusiastic, simply is not able to fix this. I am not a car mechanic but worked on machinery in manufacturing so I understand that at times issues are connected even if they seem not and the cause behind something could lie elsewhere altogether, hence my approach to look at all the issues and hope someone says 'that sounds familiar'...

I have a 2008 MB GL420 pre-facelift X164. Bought from new. It went to MB for service in the early years and then to private garage for service. Now it has spent a lot of time in service to fix isolated problems:

Clunking noise from front section underneath when driving inner city traffic, No correlation to road surface, bumps or driving style but the odd sound as if there is a broken coil spring, but there is not.
One cylinder (front right) has no injector reading
Stuttery and sluggish performance especially in rev between 1200 and 2000
Power steering very heavy
No cooling from AC
Battery discharging due to low/no running

Right now it is a non runner as it is a pain to drive and I have another car for the daily commute but naturally I will either need to fix it or make an assessment if disposing is the smarter choice. My gut feel is that the fix is not hugely expensive so I'd rather try that before being defeated. I bought a new battery anyway in a last ditch effort.

Any help, pointers or suggestions are much appreciated.

Many thanks
Tom

 

[brandwooddixon]

Non-functioning injector will cause issues on performance, have your mechanic remove them and reattached to fuel rail, check spray pattern against a sheet of cardboard.(only one or two squirts needed).
Worn drop links for front anti-roll/sway bars and suspension bottom ball joints, suspension bushes in general known to produce clunks.
AC possibly leaking condenser.
Power steering, not sure what was fitted to these vehicles, but probably hydraulic. If fluid level is okay then check for ABS sensor or steering angle sensor faults.
Battery - a faulty battery will trigger all sorts of issues. MBs can be very sensitive to battery voltage and whether things work or not.

First step, link the vehicle up to a decent battery or voltage source and reread for fault codes.

 

[captainreiss]

Thanks so much, I will hook up the new battery this weekend and read the codes.

Best wishes
Tom