Ok so this is the Code my pickup is throwing. P0470 Backpressure Sensor Circuit Error. Here is my question. 1999 Ford F-250 7.3L AFE Stage 2 Intake with 4" Exhaust, Edge CS. I'm getting low boost numbers like between 6-12 WOT. Could this Back Pressure deal be the Prob? I've checked the up pipes and they are good can't find any leaks. So the truck runs fine Turbo sounds like it Spools up Fast. The only thing is the low boost numbers and this code. Any Tips Suggestions oh ya and how to fix it?

 

Does it make a wooshing sound when idling like it's in high idle? I'd so the exhaust back pressure thing is stuck closed my bet?

 

Your EBP tube is plugged, and the sensor is more then likely as well. Clean or replace the tube and clean or replace the sensor.

12 psi with what mods?

I would check for boost leaks, remove all the boots and clean them with soap and water.

 

Ok so for the million dollar question......where is the EBP tube and sensor located? Yes I know I'm new to these trucks so bear with me. As far as I know I haven't noticed a whooshing sound....But the pickup does idol really rough. 12lbs of boost was produced on the extreme setting on my Edge CS along with an AFE Stage 2 intake and 4" Exhaust. WOT. I was surprised it only produced 12lbs. It seems like it runs fine except for the rough idle and this exhaust back pressure deal. Do u think the EBP would be part of the low boost issue?

 

The pipe comes off the from of the right side manifold and runs to the front of the timing cover. The sensor screws to the end of the pipe and is positioned vertically. I think the pipe is stainless steel. If either or both are plugged the pcm is getting bad information and can effect how much fuel is injected. Less fuel means less exhaust which turns the turbo slower and gives less boost. The question that shorty2tall asked is related to the pack pressure valve being closed which would also cause a boost problem. If the valve is closed it limits the amount of exhaust getting out which spins the turbo slower.

 

Ok I'm going to try and get that tube and sensor pulled off today. See what's going on with it. Any advice on where the back pressure valve is located and how to check it's open or closed position?

 

It is in the housing that the exhaust pipe mounts to. The control for it is on the bottom of the turbo mount in the engine valley. The wire harness that feeds control power to it is easy to reach and a rod goes from the electric hydraulic control back underneath to the actual valve butterfly arm. I don't remember off hand whether the arm is forward or back when it is open but you can try to move it and see if it is stuck.