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2009 Bluetec Underboost, LHM - DPF?

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Old Jul 6, 2016 | 03:15 PM
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R320 Bluetec
2009 Bluetec Underboost, LHM - DPF?

I have a 2009 R320 Bluetec. I bought it used and pretty much since day one it does not like driving along at a steady RPM between 2,000 and 2,500. If I do it goes into LHM with an underboost code. Below that it is pretty good, and above 80MPH it is good all day long.

I have had the intake out several times, both by me and a local indie shop. The indie shop did a smoke test, but some recent developments are making me question their service.

Last week I had it apart and pull the clip on the actuator for the fins on the turbo. I check the motion and could not feel or see any sticking, resistance, or blockage.

So, I am going to try and build a pressure tester to check the intake just in case. However, is the DPF a common clog item? I know on the domestic diesel trucks this can be an issue, especially if the vehicle is not driven hard once in a while. I don't know how much time my R spent at slow speeds and low load before I got it. Has anyone had a problem with their Bluetec going into LHM with an Underboost code and found it to be a clogged DPF?

Any other suggestions?

Thanks
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Old Jul 6, 2016 | 06:31 PM
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1922 Ford Model T / no OBD
There is low forum knowledge about Bluetec per my experience, especially those with DPF.
One thing I want to point is that you don't need to build pressure tester for the intake.
Any advanced scanner will read it.
I am using ScanGauge, but somebody pointed that any android has apps with $10 Bluetooth sender that will do that as well.
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Old Jul 6, 2016 | 06:34 PM
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I have an OBD interface and Dashcommand on my iPhone. The pressure tester is not for checking boost while under load it's to check if there are any leaks after the turbo. You pressurize the emoter intake to 20psi and let it sit. If pressure drops you have a leak. I did this with my Powerstroke and found a leak.
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Old Jul 11, 2016 | 09:21 AM
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97 s320
i remember reading someone had one of the plastic pipes after the turbo having a split in it and would leak under boost, think it was the one on the front of the motor
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Old Jul 11, 2016 | 10:04 AM
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With EGR spitting oil into intake, all intercooler side leaks show as oily spots.
My 08 Bluetec has cracks on IC hose, where mechanics kinked the hose doing other service.
Even with good layer of electrical tape, I still have oil showing on the hose.
Waiting for new hose to arrive.
On my Powerstroke intercooler boots did leak under high pressure. Same story with oily spots.
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Old Jul 11, 2016 | 02:20 PM
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I had a 7.3l Powerstroke and it leaked until I put new better hoses on. Has anyone tried aftermarket performance hose?

I need to make a pressure tester when I get home.
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