I know this has been mentioned and discussed briefly but had to remind people.
The wastgate valve and or the lines in your boost refence system can freeze leaving your turbo to boost unchecked. I have had four seperate occasions so far this winter (its not really winter yet) when this would occur, sometimes only briefly after a long sit in the cold, and some times it would take a long time for the system to thaw, dry out and and work correctly.
I beleive part of the problem is that the wastegates valve is situated under the turbo exhaust and condensation from the exhaust can drip into the valge then on shutdown freeze up. There may also be condensation in the boost reference lines.
I saw boost as high as 12-13 this afternoon going out for lunch, its about 20 degrees here now. At part throttle going up a steep grade, it pulled the same psi, so I backed out then rolled into it, and it did it again quicker.
I drove like a baby the whole lunch hour!
Oh ya, my boost controller was set to wastegate so thats 5psi, it definately was stuck good! After work all seemed to be ok, kind of strange but I drove pretty slow for a bit in traffic before really gassing it.

 

Bad controller. Same thing happened to me but I over boosted to 20+lbs. Get a new controller and you should be ok

 

I got the new STS before turbo exhaust pipe. They changed the wast gate location on it. On the new one the wast gate was moved forward about 5 inch's and rotated 90 degrees toward the passenger side. It helps boost creep by letting the exhaust out of the wast gate exit to the atmosphere.. the old one would get some back pressure from turbulence in the after turbo exhaust pipe. Also condensation on the after pipe drips strait down in to the wast gate. Then it will freeze
I will take a picture of it if you want to see it.

 

I think I've seen the new pipe configuration, but please post it anyway!
Thinking that I have to get STS involved now because I can't deal with this issue all winter, thats about 4-5 months here.


8ALTNG, I think my controller is fine, its just the temp issues here I'm thinking.
I abasolutely do not have any issues when the temps are above freezing. My truck sits in the garage all nite where its a little warmer than outside and its always ok in the morning. My truck sits in the parking lot all day at work exposed to everything outside, the worst being 15-20 degree temps right now.
When I switch my controller I always hear the soledoid vale click, just like when I installed it months ago. You said yours overboosted to 20psi, I think mine would too if I kept my foot in it long enough.
Maybe STS has some more answers.

 

Some body posted a an email from STS on here not to long ago about this freezing problem. STS's idea to fix it was to remove the valve seat from the wastegate so it wouldn't fully close and flow some exhaust though it all the time, keeping the ice melted. They said you will loose a little spool time doing that, but it will keep it from over boosting in cold weather. Just a thought.

 

Thanks for reminding me of that. Its easy to do too.
I wish there was a manual bypass or some solenoid operated valve to open in case of emergency. I have an extra TiAL wasegate to mess with, maybe I can think something up.

 

New and old E 1 pipe

 

That is interesting. Any idea of what it sounds like? Are they using a different wastegate as well? Do they have a new exit pipe as well or just cap it off?

Thanks for the pic.

 

I think they vent to atmosphere and cap the old tail pipe hole. When I put a smaller A/R housing on my set up, the waste gate didn't line up with the return to the tail pipe. I had about a 1/4 or so gap between the WG and tail pipe and I ran it like that for a couple of weeks. It sounds quite a bit different. It's more of a loud hissing noise when it is open. I didn't like it to well, so I cut the return tube off and refitted it so I could connect the wastegate back up to the tail pipe.

 

Was the fitting on the tail pipe vented to the atmosphere as well as the waste gate at this time? I am wondering if it would sound any different if it was only the sound coming through the wastegate itself? I am sure it is probably a little noisy when the wastegate is open.

Thanks kb