99 & up 7.3L Power Stroke Engine and DrivetrainDiscussion of the 99 & up 7.3L Power Stroke diesel engine and drivetrain in the 1999-Up Super Duty trucks and Excursions. No gas engine discussion allowed except on transmissions and drivetrain that pertain to all models. Please confine discussion of topics in this forum to those items that are specific to the 7.3L Power Stroke engine.
Can a leaking up pipe set a P0476 exhaust pressure control valve range/performance code? I suspect I have a leak, I think I can hear it. I also get a slight rough idle at warmup right after the high idle goes away, and it stays for a couple of minutes.
Did you mean KOER (Key On - Engine Running)?
P0476 doesn't even show up under the KOEO test in the listing.
Here's the blurb from the Service Manual.
DTC P0476 indicates an exhaust back pressure control valve performance malfunction was detected during KOER On-Demand Self Test. Possible causes: -- stuck or damaged turbocharger wastegate valve -- misadjusted or damaged linkage -- restricted exhaust -- exhaust leaks -- damaged PCM -- EPR valve -- EBP sensor
The above has an error - when they say turbocharger wastegate valve they really mean the exhaust backpressure butterfly valve. The accompanying picture shows the EBP valve tang and linkage.
Yes I meant KOER self demand. I will have to do a search on cleaning the tube. I remember reading somewhere they can rust out too, although my Arizona truck is virtually rust free.
Well I took it all apart today, and the tube was clean as a whistle inside and out, no soot or rust or holes. However the sensor itself and the mounting hole were nearly, but not completely, plugged. I'd say there was about 1/16" of an opening left. Hoping that was it, I didn't have time to run the test (got rained out) but I'll run it next weekend and post back the results.
One thing I did find was one of my fan blades has a 1/2" crack in it about two inches from the end, so I'll be ordering a fan tonight.
bigb - did you ever get this resolved? What was it? Where you having any smoke at idle when this occurred?
After cleaning the EBP sensor the code never came back. I did not ever have any smoke either, before or after. My idle still gets a tad rough for a few minutes just after the EBPV opens, but it is barely noticeable. I do still have up pipe leaks, going to change them as soon as my garage is built this summer.
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