Accelerating and Fueling

[RMVS]

Hello,

I got myself a Merc ML 320 W164 year 2008 a few months ago. Had nothing but issues since then however, I am down to the final 2 issues I need help with.

First of all there is no acceleration after a few miles. If I turn off the car then back on again it will drive fine for a few miles then have no pull again.

The codes are as follows:

P0123 Throttle/Pedal position sensor "A" circuit high

P0404 Exhaust gas recirculation "A" control circuit range/performance

I have removed the EGR pipe and EGR and cleaned both. They were both pretty clean though.




Finally, my last problem is the car won't fuel! When at the petrol station the pump thinks the car is full on the first press. I can't get more than £5 in at a time without the fuel coming back out car over me.

Any help would be appreciated. Really want to get driving the car.

 

[Teego]

The cause of both problems could be a blocked tank vent. If fuel can't displace air when filling the pump will cut off. If air can't replace fuel when driving you get fuel starvation.

 

[RMVS]

The cause of both problems could be a blocked tank vent. If fuel can't displace air when filling the pump will cut off. If air can't replace fuel when driving you get fuel starvation.

Thank you for fast reply. I am assuming the tank vent is located on the tank? Can it be cleaned ie does it have a filter that can be removed to unblock it?

Thanks

 

[Teego]

Don't know what it looks like on your car. Mine has a plastic tube from the top of the tank. Don't think it's got a filter. One thing you can try is driving with the filling cap off. If the car goes good like that you definitely have a vent problem somewhere.

 

[IanW]

I'm not familiar with the W164 specifically, but the tank vent will be a tube exiting the top of the tank, with an anti-spill valve (in case you roll the car). The tube then goes to the charcoal canister in the engine bay (to trap HC gases). The canister is usually vented to atmosphere, with a separate vent to permit the HC vapour to be drawn into the engine & burnt at a time that the ECU decides is correct.
A blockage in the pipe or failed anti-spill valve will certainly cause problems when filling.
Ian.

 

[RMVS]

I'm not familiar with the W164 specifically, but the tank vent will be a tube exiting the top of the tank, with an anti-spill valve (in case you roll the car). The tube then goes to the charcoal canister in the engine bay (to trap HC gases). The canister is usually vented to atmosphere, with a separate vent to permit the HC vapour to be drawn into the engine & burnt at a time that the ECU decides is correct.
A blockage in the pipe or failed anti-spill valve will certainly cause problems when filling.
Ian.

Thanks for comment. At the weekend I will get the car on the jacks etc and have a look for what you are describing. I will take some pics and update the post at weekend. Thanks