Mercedes ML320 99Model seems clogged and not responding to acceleration
 

Hi

I have previously had issues with the car running rich and co2 levels being high but never really caused major problems.

Recently whilst driving it has started jerking and then loses power. At high speeds it will feel very heavy and if you try to accelerate to hard it will jerk and not respond.

If this happens and the vehicle is moving from idle it will either cut out or only move once you let go of the accelerator and then you have to gently build up a bit of power.

I have seen many times the culprit as MAF and Fuel Filter. It feels as if there is a blockage and fuel cant get to where it should.

Any ideas would be much appreciated.

possible throttle postion sensor

What you suggest that I change the fuel filter and clean the MAF before changing TPS?

Is there anyway to comprehensively diagnose for TPS?

It happened the other day and when I left it over night it seemed to recover and was ok for a couple of days and today started up again for a little while.

souds like air mass sensor renew air mass ur problem will be solved...

The initial problem was in starting. I always had two have two tries to get it going. I thought it may have been injectors but was advised by a local garage against this.

In the last few weeks, randomly when I am driving the car will stumble then the revs jump, sometimes it responds to acceleration and sometimes its goes heavy.

I was advised to change the spark plugs which needed it and also the fuel filter.

The fuel filter had not been changed from original which was a shock. Since changing the spark plugs and fuel filter yesterday the starting issue has been resolved.

The stumbling still remains. Could this be because the old dirty fuel is still there and needs to be cleared or could it be something else.

By the way the Air Mass Sensor was changed in January however Dubai is very dusty and hot. Could it need replacing or is it something else?

Look forward to receiving expert advise.

MAF replaced initially with Meyle version which didn't do the trick.

Used the Bosch version following day and all seems to be well.

Now just need to fix the vibration coming from the back. Sounds like its from the prop shaft maybe its the rubber mount?

I been having similar problems. Ml runs fine until I accelerate hard, then the ml looses power and starts running rough. I would then have to turn it off and put it back on again for it to stop. I also believe its the fuel filter because it has never been changed. I changed spark plugs and did a oil change recently so I know its not the spark plugs. I will change the fuel filter and post my outcome.

My ML 350 Bluetec (48,000 miles) is in the shop right now with the same symptoms as raygoor. I will post all the details once I get the diagnosis. The last time my engine light came on three months ago I had to get the regen "cooked" due to excess dirty buildups. It had been running fine up until now.