My engine started idling rough at stop lights. Now it has a miss (cough) when I start it up and has continued to cough when I was at speed. I pulled p0470 code. What do you think?
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2001 Ford F-250 Super Duty Question: Engine idles rough
Answer #1DaveJHM December 21, 2010, 20:37Master
The P0470 is a code for Exhaust Back Pressure Sensor issue (EBP sensor). A fault was detected driving. Typical causes are defective sensor and / or wiring connector.
Do you have a performance chip or programmer for this truck?
I suspect that also you could have injector wiring harnesses with intermittent faults under the valve covers. Fairly common on these.
Replyjack 21, December 22, 2010, 16:12Rookie
Yes I have a superchip in the truck , that was in when I bought it. I took it off performance and put it on safe tow. I usually have my welding trailer behind it. The miss is getting worse. Today it would miss 5miles down the road and at 65mph. It was at normal opperating temp , it was not cold. It doesnt do it all the time just a miss now and agian. Thanks for the info. How do check if I intermitten faults under the valve covers?
ReplyDaveJHM, December 22, 2010, 21:19Master
The EBP code is a direct result of the Superchip, most likely; for that reason, I wouldn't get too excited about it affecting your rough running issue.
A 2001 7.3L isn't going to throw a ton of codes for misfire issue or injector harness issues all the time. The harnesses are common for failure on these. A "wiggle" test of the harness while the vehicle is running will show if the problem is there. However, i would probably just proactively replace the harnesses and recheck operation, unless you know they have been replaced before, recently.
You could also have issues with injectors or the IDM (injector driver module). You could have an ICP (injector control pressure) issue as well. Beyond the harnesses, I would probably consult a good Power Stroke Diesel tech to help out with continued diagnosis. Good luck and Happy Holidays!
Replyjack 21, December 24, 2010, 06:51Rookie
Thanks for your detailed info. Merry Cristmas