CODE: Exhaust Pressure To High
Thread Starter
Junior Member
Joined: Sep 2012
Posts: 36
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From: Maryland
2008 GL 320 CDI
CODE: Exhaust Pressure To High
Anyone have any ideas on what “exhaust pressure to high” code could mean? I had my fuel pump and sensor replaced, and the now check engine light is on. Car hesitates when you need to accelerate really fast onto a ramp.
Super Member
Joined: Feb 2009
Posts: 711
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From: NW corner of CONUS
2008 GL 320 CDI, 2004 VW V10 Touareg TDI
It needs to be read by a dealer computer diagnostic system. If it IS truly exhaust pressure too high, it might be that you have a bad sensor at the DPF OR (and keep you finger's crossed that it ISN'T this) the DPF itself is plugged and needs to be replaced $$$$!
Thread Starter
Junior Member
Joined: Sep 2012
Posts: 36
Likes: 0
From: Maryland
2008 GL 320 CDI
Thank you FourDiesel… my mechanic did say it could be the sensor, but typically the sensor will say it’s bad. Right now we are trying the cheaper fixes. Cleaned Fuel injectors cleaned the muffler system. I figure we will replace the sensor first to see if it clears the system error. If not…here we go with the DPF. By the way what does DPF stand for?
I don’t understand why this went bad, how they two issues are related. One day the car was running great, filled the tank with diesel and 20 miles later it stalls. We replaced the fuel pump with sensor and then the check engine light goes on with this issue!!!
I don’t understand why this went bad, how they two issues are related. One day the car was running great, filled the tank with diesel and 20 miles later it stalls. We replaced the fuel pump with sensor and then the check engine light goes on with this issue!!!
Out Of Control!!
Joined: Aug 2010
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From: Charlotte NC area
2019 WS222 S450 4-Matic / 2007 W211 E350 4Matic (Sold) / 2008 X164 GL320 CDI
Cleaning the DPF is a process your mechanic probably can not do properly unless he is a high volume diesel shop.
Super Member
Joined: Feb 2009
Posts: 711
Likes: 11
From: NW corner of CONUS
2008 GL 320 CDI, 2004 VW V10 Touareg TDI
DPF stands for Diesel Particulate Filter. It provides a catalyst surface to catch the particulates while they are being oxidized in the hot, oxygen rich exhaust. They - the filter media/catalyst - will eventually get clogged with contaminants or ash particles. If the clogging is mostly carbon it CAN be burned off. If it is ash that will not work. A new DPF filter for my '08 from my dealer cost about $3200.00 US [fortunately it was covered under warranty].
The sensor measures the differential pressure across the DPF. Too much OR to little differential triggers the CEL. The sensor itself is also a common failure item.
The sensor measures the differential pressure across the DPF. Too much OR to little differential triggers the CEL. The sensor itself is also a common failure item.
