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Discussion Starter · #1 ·
When I’m at full throttle and the boost gauge reaches 8, it just stops, almost feels like hitting a wall. The engine light comes on for two seconds and disappears. This only happens when I’m at full throttle. I fixed my boost leak with some metal piping, so I doubt it’s related to that.
 

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Sounds like fuel cut? That's Toyota's way of saying that you're having too much fun....and to prevent possible engine damage. Some people circumvent this, but I'm not one of them.
 

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That's fuel cut. Stock boost gauge, or an aftermarket gauge? If you've got a boost controller, turn it down.
 

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Stock everything.
If it's hitting 8psi on the stock boost gauge, there's something changed from stock to raise the boost level.
Stock everything hits 4-5psi on the stock gauge.

Is the wastegate shimmed, or is there any monkeying with the wastegate or vacuum line to the wastegate?
 

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Discussion Starter · #6 ·
If it's hitting 8psi on the stock boost gauge, there's something changed from stock to raise the boost level.
Stock everything hits 4-5psi on the stock gauge.

Is the wastegate shimmed, or is there any monkeying with the wastegate or vacuum line to the wastegate?
i just checked everything, everything seems to be connected properly and it is not shimmed. Im not sure if thats a good thing or a bad thing lol
 

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i just checked everything, everything seems to be connected properly and it is not shimmed. Im not sure if thats a good thing or a bad thing lol
I promise that something has been monkeyed with or changed if you're pegging the stock boost gauge.

Try using a simple bicycle pump to test the WG operation directly - if the WG is somehow seized and not opening it could do this sort of thing on a stock setup. It should start moving the WG rod almost immediately with any pressure at all, like 2-3psi should show movement, it should be wide open by 6-7psi. If there's any washers between the WG actuator and the compressor housing, that's what's upping the boost and you need to remove those washers and start over again.

Past that, these other dudes suggested good things to check - gutted cats will usually see an increase in boost but I haven't seen a 7M-GTE so 'healthy' that it'd hit fuel cut from gutted cats alone, usually a turbo-back bellmouth downpipe and catless exhaust will see ~8-9psi with no other changes, and fuel cut is usually around 11.5psi.
 

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Discussion Starter · #10 ·
I promise that something has been monkeyed with or changed if you're pegging the stock boost gauge.

Try using a simple bicycle pump to test the WG operation directly - if the WG is somehow seized and not opening it could do this sort of thing on a stock setup. It should start moving the WG rod almost immediately with any pressure at all, like 2-3psi should show movement, it should be wide open by 6-7psi. If there's any washers between the WG actuator and the compressor housing, that's what's upping the boost and you need to remove those washers and start over again.

Past that, these other dudes suggested good things to check - gutted cats will usually see an increase in boost but I haven't seen a 7M-GTE so 'healthy' that it'd hit fuel cut from gutted cats alone, usually a turbo-back bellmouth downpipe and catless exhaust will see ~8-9psi with no other changes, and fuel cut is usually around 11.5psi.
huh, interesting. well i honestly just want it to be reliable. Anyway to turn down the boost? i dont have a boost controller
 

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Discussion Starter · #11 ·
I promise that something has been monkeyed with or changed if you're pegging the stock boost gauge.

Try using a simple bicycle pump to test the WG operation directly - if the WG is somehow seized and not opening it could do this sort of thing on a stock setup. It should start moving the WG rod almost immediately with any pressure at all, like 2-3psi should show movement, it should be wide open by 6-7psi. If there's any washers between the WG actuator and the compressor housing, that's what's upping the boost and you need to remove those washers and start over again.

Past that, these other dudes suggested good things to check - gutted cats will usually see an increase in boost but I haven't seen a 7M-GTE so 'healthy' that it'd hit fuel cut from gutted cats alone, usually a turbo-back bellmouth downpipe and catless exhaust will see ~8-9psi with no other changes, and fuel cut is usually around 11.5psi.
Ok, now im a bit scared. After reading around for a bit, it seems that turbo flutter is a bad thing? i thought it was normal. I will check the bov tomorrow but i doubt thats related
 

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Things might look fine
i just checked everything, everything seems to be connected properly and it is not shimmed. Im not sure if thats a good thing or a bad thing lol
The vacuum line from the turbo to the wastegate might be cut but not noticeable until you're under boost, so the wastegate is not getting a full signal.
Did the issue recently start, or did it always do this since you've had the car?
 

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Discussion Starter · #13 ·
Things might look fine

The vacuum line from the turbo to the wastegate might be cut but not noticeable until you're under boost, so the wastegate is not getting a full signal.
Did the issue recently start, or did it always do this since you've had the car?
Since I had the car. Its only been a month so I hadn’t noticed anything
 

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Discussion Starter · #14 ·
I promise that something has been monkeyed with or changed if you're pegging the stock boost gauge.

Try using a simple bicycle pump to test the WG operation directly - if the WG is somehow seized and not opening it could do this sort of thing on a stock setup. It should start moving the WG rod almost immediately with any pressure at all, like 2-3psi should show movement, it should be wide open by 6-7psi. If there's any washers between the WG actuator and the compressor housing, that's what's upping the boost and you need to remove those washers and start over again.

Past that, these other dudes suggested good things to check - gutted cats will usually see an increase in boost but I haven't seen a 7M-GTE so 'healthy' that it'd hit fuel cut from gutted cats alone, usually a turbo-back bellmouth downpipe and catless exhaust will see ~8-9psi with no other changes, and fuel cut is usually around 11.5psi.
Turns out I can blow through the BOV. I will be ordering a new one soon.
 

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Discussion Starter · #15 ·
Things might look fine

The vacuum line from the turbo to the wastegate might be cut but not noticeable until you're under boost, so the wastegate is not getting a full signal.
Did the issue recently start, or did it always do this since you've had the car?
After removing the accordion hose, I inspected the vacuum line but I don’t see any “visible” cracks, connections seem good. I checked all the other vacuum lines and they seem to be in good shape too. I’m betting on a crapped actuator. Anyway to test that at home with basic tools?
 

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After removing the accordion hose, I inspected the vacuum line but I don’t see any “visible” cracks, connections seem good. I checked all the other vacuum lines and they seem to be in good shape too. I’m betting on a crapped actuator. Anyway to test that at home with basic tools?
Yes. As I already described. Get a simple bicycle pump and a ball inflator needle, clamp a vacuum hose tightly over it, and run the vacuum hose to the gold UFO shaped wastegate actuator on the side of the turbo. Ideally use a bike pump with a built in pressure gauge. Pump the bike pump up and it should almost immediately begin pushing the wastegate open, you'll see this as the rod pushing outward and moving the lever on the side of the exhaust housing.
 

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Discussion Starter · #17 ·
Yes. As I already described. Get a simple bicycle pump and a ball inflator needle, clamp a vacuum hose tightly over it, and run the vacuum hose to the gold UFO shaped wastegate actuator on the side of the turbo. Ideally use a bike pump with a built in pressure gauge. Pump the bike pump up and it should almost immediately begin pushing the wastegate open, you'll see this as the rod pushing outward and moving the lever on the side of the exhaust housing.
thank you.
 

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Discussion Starter · #18 ·
Yes. As I already described. Get a simple bicycle pump and a ball inflator needle, clamp a vacuum hose tightly over it, and run the vacuum hose to the gold UFO shaped wastegate actuator on the side of the turbo. Ideally use a bike pump with a built in pressure gauge. Pump the bike pump up and it should almost immediately begin pushing the wastegate open, you'll see this as the rod pushing outward and moving the lever on the side of the exhaust housing.
Hey you were right! The actuator crapped itself. It is not moving at all below 9, starts to move around 10 psi. I found an actuator on driftmotion, but the Land Cruiser one is way cheaper. Wondering if I could somehow transplant the bracket.
 

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Hey you were right! The actuator crapped itself. It is not moving at all below 9, starts to move around 10 psi. I found an actuator on driftmotion, but the Land Cruiser one is way cheaper. Wondering if I could somehow transplant the bracket.
Nope, different pressure rating and different compressor cover orientation. The bracket is spot welded onto the actuator housing.
Get the one that is for sure correct for your car. If they interchanged, places like Driftmotion would sell the cheaper one to solve the same problem.

Be very careful when you replace the actuator. The bolts will come out easy but the clip that holds the actuator rod onto the wastegate flapper stud is VERY easy to lose. I recommend having a friend come over, use a pair of tiny needlenose on the closed side of the clip to hold it securely, and have the other person use another pair of needlenose to push both ends of the open side off the stud from the opposite way.
Having that first person holding it TIGHTLY with needlenose will keep it secure and save you from a 'dammit' moment as it shoots off to Mars or wherever those parts end up when they disappear forever.
 

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Discussion Starter · #20 ·
Nope, different pressure rating and different compressor cover orientation. The bracket is spot welded onto the actuator housing.
Get the one that is for sure correct for your car. If they interchanged, places like Driftmotion would sell the cheaper one to solve the same problem.

Be very careful when you replace the actuator. The bolts will come out easy but the clip that holds the actuator rod onto the wastegate flapper stud is VERY easy to lose. I recommend having a friend come over, use a pair of tiny needlenose on the closed side of the clip to hold it securely, and have the other person use another pair of needlenose to push both ends of the open side off the stud from the opposite way.
Having that first person holding it TIGHTLY with needlenose will keep it secure and save you from a 'dammit' moment as it shoots off to Mars or wherever those parts end up when they disappear forever.
Lol, I’ll keep that in mind
 
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