I have a code P0476 (exh pressure control valve perform) well took it off and it was pretty clogged. Got tube fitting and sensor cleaned reinstalled did a KOER test and code is still there. Also it idles a little rough now after cleaning it, at times more then before I cleaned it. Is it time for a new EBPS.

Thanks

 

i thought thatther was a tsb for the ghost p0476 code.not sure though.when you did the running test did the butterfly valve open during the test.

 

If the tube is clear and has no holes in it, then I'd guess it's your sensor... you'd need a scan tool to read the pressure off the sensor to see if it's reading right. I know one guy on here said his sensor was stuck reading 19PSI I think...

 

When scanning what test am I looking at? Also when doing KOER test I can hear the valve closed but not as loud,if that makes sense.

 

It's a live data reading... you want to look at that while the truck is operating. I don't remember what is normal at idle, but I think it's a few PSI, but when you're driving it and nail it, you should see 30 to 50PSI. Am I right, fellas?

 

Jon what PSI am I looking at? Is it back pressure?

 

Yes, it's "Exhaust Back Pressure".

And also, the back pressure valve isn't related to the back pressure tube and sensore. The tube and sensor read the back pressure in the headers whereas the the back pressure valve is a valve in the exhaust right on the backside of the turbo that closes when the motor is cold to aid in warming up.

 

Okay I will check that today.

So code p0476 has nothing to do with the EBPS?
What is the adjustment on the EBPV and how?
Also during warm up its not as loud as my other truck could there be a problem their?

 

The PID value for your EBPV sensor should read 0.8-0.95 volts at low idle. High idle should be 0.9-3.0

The EBP solenoid should read 7.5v at idle and 12v at high idle (according to this chart...) Check out page 4 of the file attachment below...

A real easy way to double check your EBPV sensor is to check the values with the engine off. The Exhaust Back Pressure in psi should match Manifold Absolute Pressure (or be pretty close, like within .5 psi). Should also match barometric pressure as well so you might check your local weather to see what the pressure is at the time you take your readings. If you don't have a weather station nearby, then you can determine Baro by starting your engine and checking Manifold Absolute Pressure and subtract Manifold Gauge Pressure (or add the negative number...which ever makes more sense for you)

With your engine running and warmed up, your EBPV should be about 14.5-15psi at idle and will increase as you drive it. I've never seen anything over 40 psi at heavy throttle (but then again I haven't really monitored it all that closely...)

Hope some of this info helps.

 

So what else is there besides the valve and the solenoid to open and close it? As far as back pressure, I've seen over 50PSI on mine a few times...

 

Okay I did a test exhbackprs (psi)15@ idle.and 30@WOT. EBP (v)1.06@idle Am I looking at the right numbers?

 

So it seems my Exh back prs numbers are good?
But my EBP(V) seems a little high.Its 1.09v @idle and just about the same or a tad bit higher @high idle.Correct me if I'm wrong

Thanks

 

Isn't it common for the valve to stick? Not sure... unless it's leaking oil (might wanna check into that), it might just need a rebuild. Clay sells the kit unless you wanna delete it altogether... I'm not too sure about the numbers. I'm sure someone who knows more about it will chime in... guys?

 

Well, to the best of my knowledge, the EBPV system is similar to the high pressure oil system in that there is a device, a regulator and a sensor. For the EBPV system we have the actual butterfly valve itself which is actuated by a push rod via hydraulic pressure from the engine (low pressure oil). There is an electrical valve of some sort that opens or closes the supply of oil to the actuator. So, when the PCM wants the valve to close, it 'makes' the circuit to the electrical valve by providing a ground. That valve must then allow oil to accumulate inside the actuator and push out on the rod which closes the exhaust valve. I am not real sure how the electrical switch works exactly...meaning I don't know if it allows oil to enter the accumulator or prevents it from bleeding (sorta like the IPR at the HPOP does). At any rate, I do believe the electrical switch is all or nothing, meaning it's on or off with no duty cycle in between. All this stuff is at the pedestal under the turbo.

Then, on the exhaust manifold side, there is a small tube that connects the left and right side manifold and has a place for a sensor (right behind the serpentine belt idler pulley). This sensor can detect when the EBPV closes by reading an increase in pressure. It also has some other uses for the PCM so it should be kept clean.

Here are some photos of that sensor from Guzzle's website.

 

I see... so, if the EBPS wasn't working right, it could throw a code, but his PSI numbers sound about right. Maybe I'm imagining things, but isn't it common for the valve to stick sometimes?