Could it be 3-port allowing all air to go through instead?
0 wastegate duty cycle
I have an odd problem. I'm tuning a built evo mr, and without changing the tune (or any hardware), it started boosting about 10psi less one day out of the blue.
We looked over the car and everything appeared to be in order, so I took the car out for a few pulls and logged just to make sure it wasn't something electrical.
To my surprise, the WGDC was reporting 0%, despite it being set to 50% or higher in the ranges I logged. Yes, I double checked this. I also don't have any boost correction modifiers that are significant enough to zero it out. My alt maps are also set to higher WGDC numbers.
As far as I know, the reported WGDC is the output from the ECU itself, rather than some kind of observed value, so it wouldn't make any sense for it to be something like a failed wastegate solenoid. In my mind, that should just accept the input but just not do it's job.
So before I go too crazy diagnosing this, I wanted to see if anyone has had a similar issue. Intuition tells me it's something in the ECU somewhere which is deciding to send the zero over the wire. I may just flash a stock tune on the car (with some maf and injector scales) and just do a quick 2nd gear pull to see what happens, but I just figured this would be an interesting thing to discuss.
We looked over the car and everything appeared to be in order, so I took the car out for a few pulls and logged just to make sure it wasn't something electrical.
To my surprise, the WGDC was reporting 0%, despite it being set to 50% or higher in the ranges I logged. Yes, I double checked this. I also don't have any boost correction modifiers that are significant enough to zero it out. My alt maps are also set to higher WGDC numbers.
As far as I know, the reported WGDC is the output from the ECU itself, rather than some kind of observed value, so it wouldn't make any sense for it to be something like a failed wastegate solenoid. In my mind, that should just accept the input but just not do it's job.
So before I go too crazy diagnosing this, I wanted to see if anyone has had a similar issue. Intuition tells me it's something in the ECU somewhere which is deciding to send the zero over the wire. I may just flash a stock tune on the car (with some maf and injector scales) and just do a quick 2nd gear pull to see what happens, but I just figured this would be an interesting thing to discuss.
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Well, the way it works is that 0% WGDC is wide open, and 100% WGDC is closed.Could it be 3-port allowing all air to go through instead?
So right now, that's exactly what's happening, the 3 port is allowing all air to go through. But I'm TELLING it to do 60-85%. And it seems like the ECU is not sending that signal out.
Could it be a damaged wireloom? A pinched wire, damaged at some point while modding the car?
Need logs from a pull. I believe BWGDC is a TPS X RPM table correct? Perhaps a bad TPS sensor? I'm guessing that would cause lots of other issues, but some logs would help clear the air on a lot of things.
Whats your coolant temp? Maybe bad temp sensor.
Have you reflashed with a different rom id? tried different map?
I have seen this before- I dont recall the solution
cb
I have seen this before- I dont recall the solution
cb
I dont think the EVO X has a defined WGDC coolant correction table in most XML's-
the evo 8/9 do- so if you dont reach a predetermined coolant temp the car wont start referencing the boost table- but its typically a percentage base-
I dont think a X will start with a bad coolant temp sensor- but I may be wrong-
cb
the evo 8/9 do- so if you dont reach a predetermined coolant temp the car wont start referencing the boost table- but its typically a percentage base-
I dont think a X will start with a bad coolant temp sensor- but I may be wrong-
cb
I would start with swapping to another 3-port since it's that easy. Wires don't just pinch on their own.
The solenoid does NOT provide any kind of feedback to ECU, thus the ECU doesn't know if the solenoid is stuck or not. The value that appears in logs refers to the value commanded by ECU, not necessarily the real value. For some reason, the ECU is not even telling the solenoid to change its position.
Yes, correction is also 0.Did you log WGDC Correction?
The throttle position is correct.Need logs from a pull. I believe BWGDC is a TPS X RPM table correct? Perhaps a bad TPS sensor? I'm guessing that would cause lots of other issues, but some logs would help clear the air on a lot of things.
Hmm, I don't know but it should have been warm. I'll look into that.Whats your coolant temp? Maybe bad temp sensor.
That's what I'm screaming. And that's what is baffling me.The solenoid does NOT provide any kind of feedback to ECU, thus the ECU doesn't know if the solenoid is stuck or not. The value that appears in logs refers to the value commanded by ECU, not necessarily the real value. For some reason, the ECU is not even telling the solenoid to change its position.
I tried a different ROM, but not a completely different ROM. I'll likely try that first.Have you reflashed with a different rom id? tried different map?
I have seen this before- I dont recall the solution
cb
Are you using RAX or Tephra patches?
should try with stock or different boost solenoid.
The solenoid does NOT provide any kind of feedback to ECU, thus the ECU doesn't know if the solenoid is stuck or not. The value that appears in logs refers to the value commanded by ECU, not necessarily the real value. For some reason, the ECU is not even telling the solenoid to change its position.
Gotcha guys. Brainfart on my end.That's what I'm screaming. And that's what is baffling me.
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