12 replies to this topic

[Mitch01]

Courtenay stage 2, alloy intake pipe, Forge re-circ valve, standard turbo. I have a boost gauge fitted when accelerating hard the boost reaches 17-18psi then suddenly drops down to zero. I have changed the two solenoids checked all boost and vacuum pipes but still the same, could it be the actuator? If so how can I check it. Really need to get this sorted ASAP have a trackday Monday. Any help will be very much appreciated. Thanks Mitch

[Ormes]

Courtenay stage 2, alloy intake pipe, Forge re-circ valve, standard turbo.

I have a boost gauge fitted when accelerating hard the boost reaches 17-18psi then suddenly drops down to zero.

I have changed the two solenoids checked all boost and vacuum pipes but still the same, could it be the actuator? If so how can I check it.

Really need to get this sorted ASAP have a trackday Monday.

Any help will be very much appreciated.

Thanks

Mitch

If its not he actuator, possibly boost / vacuum soleniod. I have a brand new boost solenoid and used vacuum solenoid if you'd like to try them.

I am not familiar with testing the actuator but understand there is a way of doing it.

Cheers

[VXTyrant]

I'd also know how to set and test the actuator

[SteveA]

Sounds like your wastegate is fully opening You can test the actuator by removing the top heat shield getting a small spanner (8mm IIRC) onto the actuator shaft above the wastegate nuts and applying some downward pressure. It shouldn't be easy as the spring will resist this but with a bit of pressure you should be able to push it down untill the wastegate is fully open. As I understand it, when a turbo hits max boost (overboost) it applies pressure to the top of the actuator which forces it downward opening the wastegate to relieve pressure. The ammount this opens is set by the adjustment nuts which hold the shaft to the wastgate lever. The position of these nuts controls the held boost level. By your description I think the spring is resisting but as soon as the wastgate opens it is not bring controlled resulting in a total loss of boost.

[Duncan VXR]

It could be the actuator but if its holding 18psi suspect its doing something, could be overboosting and ECU venting the boost. But would be interested to prove the boost system and all other bits (know you state you have) did the fault occur since fitting any of those parts? To test the actuator you need to pressurize it with a boost gauge connected and see what the reading is as the wastegate penny starts to move (creep) - you can use mitivac's etc but I made my own tester with old compression tester (doesnot let air out until released via button) and connected to small hand pump and worked fine for setting the act static break off point Cant see its the wastegate penny sticking open as that would give diff results Maybe the dv is sticking open, not holding shut? Hard to say without seeing it in action tbh will be something simple, always is DG

[Ormes]

Courtenay stage 2, alloy intake pipe, Forge re-circ valve, standard turbo.

I have a boost gauge fitted when accelerating hard the boost reaches 17-18psi then suddenly drops down to zero.

I have changed the two solenoids checked all boost and vacuum pipes but still the same, could it be the actuator? If so how can I check it.

Really need to get this sorted ASAP have a trackday Monday.

Any help will be very much appreciated.

Thanks

Mitch

If its not he actuator, possibly boost / vacuum soleniod. I have a brand new boost solenoid and used vacuum solenoid if you'd like to try them.

I am not familiar with testing the actuator but understand there is a way of doing it.

Cheers

Sorry mate, just re-read your original post and seen you changed the 2 solenoids.
What spring do you have in your forge?

[Mitch01]

Thanks all for all the replies guys, please keep them coming I have checked the actuator this morning, it appears to be moving freely. I set up a gauge and air line on the actuator, the actuator arm started to move at 8 psi is this right? I have taken out the re-circ valve and inspected and again all seems fine and is moving freely it is fitted with a yellow spring. I'm starting to think that maybe one of the new solenoids that I fitted may also be faulty. Mitch

[Duncan VXR]

sound fine on the actuator iirc sure 8psi is std - you can also test the act by unplugging the solinoid and real boost reading should be 8psi Time to double check everything I think DG

[Mitch01]

Does anybody know if Courtenay's is open? I have been trying to call them for two days now, but just get recorded message "thanks for calling Courtenays" then line goes dead.

[Duncan VXR]

Should be - try mailing

[Mitch01]

Have replaced a couple of vacuum hoses that I thought might be the problem and the car is alot better but not perfect it is still dumping all it's boost but it's doing it now and again rather than most of the time. One thing that I noticed while putting everything back together was that the air box was hanging off it's bracket and the pipe that attaches to the air box was hanging off, could this cause boost issues? The car sounds different now this pipe has been re-attached. Going in the right direction so I'm going to replace all the remaining vacuum hoses tomorrow with silicon hoses and cable tie them on, let's hope that does the trick.

[Ormes]

Have replaced a couple of vacuum hoses that I thought might be the problem and the car is alot better but not perfect it is still dumping all it's boost but it's doing it now and again rather than most of the time.

One thing that I noticed while putting everything back together was that the air box was hanging off it's bracket and the pipe that attaches to the air box was hanging off, could this cause boost issues? The car sounds different now this pipe has been re-attached.

Going in the right direction so I'm going to replace all the remaining vacuum hoses tomorrow with silicon hoses and cable tie them on, let's hope that does the trick.

Glad you made some progress.

Out of interest, were the 2 solenoids you fitted the exact same part number or the specific front and rear? If so that may contribute to splitting a pipe on the inlet side.

Re: the pipe hanging off the air box... do you mean the pipe that sits in the ear or the AMM to airbox pipe. The one in the ear will have no real impact. If your air box was not connected to the AMM, all manner of sh1t could have been dragged in.

[Mitch01]

Glad you made some progress.

Out of interest, were the 2 solenoids you fitted the exact same part number or the specific front and rear? If so that may contribute to splitting a pipe on the inlet side.

Re: the pipe hanging off the air box... do you mean the pipe that sits in the ear or the AMM to airbox pipe. The one in the ear will have no real impact. If your air box was not connected to the AMM, all manner of sh1t could have been dragged in.

Yep the solenoids were replaced like for like, one of the pipe connectors (rubber bit) on the inlet solenoid split as I pulled it off so I'm going to replace all of the vacuum pipes with silicon.

I think this is a job that all turbo owners should think of doing, as some of the connectors on the vacuum pipes are showing signs of age ie. cracking.