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512Westy
04-28-2013, 09:12 PM
My engine light came on, and have intermentent loss of power. Typically worse under heavy load (climbing a hill from slow start). the code Autozone read was P0489 and they interpret this as EGR solenoid circuit short circuit. Other lists seem to show it as Exhaust Gas ReCircuitulation Control Circuit Low.

Any hints?
2004 2500 - (Westfalia Airstream camper)
live in central texas.
original turbo resonator, but i am changing it out to a new OEM model recently bought as a back up.
40k miles

thanks

512Westy
04-28-2013, 09:47 PM
Also, I notice oily residue around the Intake Air Temp Sensor and the Boost Pressure Sensor.
That portion of the hose is freshly oily.

autostaretx
04-28-2013, 10:42 PM
I would vote for an air leak in that area (near the IAT sensor and BPS)
Also check for oil/tar near/under the resonator.

Having the hood open and listening/watching/feeling for leaks while someone revs the engine might give a clue
(be careful about the radiator fans)
The EGR may be what's spraying the oil (it's near there)

--dick

512Westy
04-28-2013, 11:57 PM
I changed the turbo resonator to the new unit, but when inspecting the old unit, I don't see any signs of a leak. I blew into it, while holding the other end and did not notice any leak. Obviously, nothing dramatic at least. I understand it could leak while under heavier pressure.

I took the hose off from the EGR to the boost pressure sensor and found lots of oil being blown into the hose from the aluminum manifold at the EGR. Is this suppose to be taking place? Inspected the hose and did not find any cracks or signs of failure.

After unclipping the connectors, taking the air temp sensor out, and wiggling everything, put everything back together and started engine and no warning light.

will have to test drive and put it under a load.

512Westy
04-29-2013, 12:12 AM
There was some tar like residue (or heavy thick oil) on the turbo housing when i took the resonator off. What is that an indication of? the hose leading to the resonator had a very slight oily residue but nothing significant.

autostaretx
04-29-2013, 12:55 AM
tar like residue
The tar-like reside is/was diesel fuel or engine oil that escaped near the resonator and was baked on by the heat of the turbo.
(it comes from places like oil passing through the turbo bearing, recirculated exhaust and the output of the PCV system)

The existence of mild amounts of oil in the intake air stream is "normal".
If you pull out your IAT sensor, you'll probably see a drop of oil on it.

The coating you saw (depending upon where it's at) could've come from a cracked O-ring on the resonator/turbo joint,
escaped gasses from the resonator's own glued seal (the area where they fail), or (rarer) some leak in the big rubber hose between the resonator and the intercooler. Evidently NCV3's have failure-prone hose end joints.

Of course, the tar you saw could've been sourced by some other leak (oh, joy), but usually it's the turbo-related stuff.

--dick