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Boost stuck at 5psi

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#1
Having an issue where the car won't boost past 5psi. Currently the car has. After market intercool and mishimoto intake. I'm on a custom tune from Adam@ tuneplus. The issue always comes up after about of mile of driving from Turing on the car. At first I thought my wastegate was going out but I notice that if I would switch off the car and turn it back on all the sudden I have boost again. So I then thought maybe the wastegate solenoid. So I purchased a brand new one from Ford. The issue continued. I've been monitoring the WGDC actual on the accessport port and notice that one the car is just turned on the wastegate sits at about 8% at this point in can go WOT and will hit peak boost ~25psi but after about a few min if the car being on all the sudden the WGDC goes to 0% and stays there untill I turn the car back off and on. I've read somewhere that if the WGDC is a 0 it means that there is no input going to the solenoid. So I'm lost now did the brand new solenoid that I bought come defective or is there other sensors that control the boost? Is my wastegate getting stuck if so why does shutting the car off and back on fix the problem momentarily? Anyone here ever run into a similar issue?

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TyphoonFiST

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#2
Having an issue where the car won't boost past 5psi. Currently the car has. After market intercool and mishimoto intake. I'm on a custom tune from Adam@ tuneplus. The issue always comes up after about of mile of driving from Turing on the car. At first I thought my wastegate was going out but I notice that if I would switch off the car and turn it back on all the sudden I have boost again. So I then thought maybe the wastegate solenoid. So I purchased a brand new one from Ford. The issue continued. I've been monitoring the WGDC actual on the accessport port and notice that one the car is just turned on the wastegate sits at about 8% at this point in can go WOT and will hit peak boost ~25psi but after about a few min if the car being on all the sudden the WGDC goes to 0% and stays there untill I turn the car back off and on. I've read somewhere that if the WGDC is a 0 it means that there is no input going to the solenoid. So I'm lost now did the brand new solenoid that I bought come defective or is there other sensors that control the boost? Is my wastegate getting stuck if so why does shutting the car off and back on fix the problem momentarily? Anyone here ever run into a similar issue?

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How was the pre-load set on the wastegate? Has it always had this problem since install of the performance parts? Are the boost Solenoid lines correctly routed? Are they at any funny angles so the hose may pinch shut? What type of hose was used? Have you done a boost leak test?

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OP
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Thread Starter #3
How was the pre-load set on the wastegate? Has it always had this problem since install of the performance parts? Are the boost Solenoid lines correctly routed? Are they at any funny angles so the hose may pinch shut? What type of hose was used? Have you done a boost leak test?

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So I'm still on stock turbo so I assume the wastegate is on the same preload setting from factory. The problem happens after a few hard launches at the track. Before I never had the issue and ran the car just fine with all current mods and tune. But after that time in the track it began to do it. The boost solenoid k bought cane with hoses pretty sturdy hoses. I made sure that I routed in the correct orientation. But since the problem continued even after the new solenoid. My guess is that the original solenoid was working just fine. Could it be a fuse or relay that may be going out? The weird thing is that if it stops working, and I turn on the car off and on real quick at a stop light all the sudden the boost solenoid is getting a reading again. Could it maybe be a faculty diverter valve? Staying stuck open.

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St. Paul
#4
So I'm still on stock turbo so I assume the wastegate is on the same preload setting from factory. The problem happens after a few hard launches at the track. Before I never had the issue and ran the car just fine with all current mods and tune. But after that time in the track it began to do it. The boost solenoid k bought cane with hoses pretty sturdy hoses. I made sure that I routed in the correct orientation. But since the problem continued even after the new solenoid. My guess is that the original solenoid was working just fine. Could it be a fuse or relay that may be going out? The weird thing is that if it stops working, and I turn on the car off and on real quick at a stop light all the sudden the boost solenoid is getting a reading again.

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This may be a silly question as it sounds like you have experience with the accessport and not having this issue in the past, but it burned me once or twice.

Is there any chance you are accidentally putting the car into the economy map using the cruise control?

I only ask as you say its limited to 5psi, and it happens after a couple minutes (maybe you use the cruise control in this time)
 


OP
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Thread Starter #5
This may be a silly question as it sounds like you have experience with the accessport and not having this issue in the past, but it burned me once or twice.

Is there any chance you are accidentally putting the car into the economy map using the cruise control?

I only ask as you say its limited to 5psi, and it happens after a couple minutes (maybe you use the cruise control in this time)
Yea I thought this was maybe it. But I spoke to a Cobb tech and he said unless my tuner set a map for economy mode there's no way I could be in Cobbs economy mode without reflashing the car back to cobbs OTS tune.

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CarGuy

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#6
Yea I thought this was maybe it. But I spoke to a Cobb tech and he said unless my tuner set a map for economy mode there's no way I could be in Cobbs economy mode without reflashing the car back to cobbs OTS tune.

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My tuner set up economy mode so don't rule that out.

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