Wastegate solenoid?

[87TTypeKid]

I was doing a bit of reading the other day in that book "The Power-Pac Buick: Performance and Restoration Tips", and something caught my attention. They were talking about a street chip available with many of the same functions as the TurboTweak 93 octane chip I have installed already. Of the things they mentioned, I recall them saying that "the chip increases boost to 17 psi". I am aware that mine is set up for 16-17 as well. Is this supposed to be an automatic change? I was always under the impression any boost adjustment had to be done with a controller or the actuator rod.

This being said, the one component I could theoretically see handling this function is the wastegate solenoid on the passenger side valve cover that the boost lines from the turbo are attached to. What does this part do? My guess is that since one end is covered by a little filter sock that its function is to regulate how much boost pressure the wastegate actuator sees. Is this true? Why is there a plug going into it?

And, if this is infact supposed to regulate boost, I doubt that mine is. Assuming the chip adjusts this automatically, I am still at 13 psi. I tried bombing around with it unplugged, and switching the vacuum ports, but none of this altered my results. Any insight? Thanks.

 

[mikestertwo]

The solenoid does control boost if everything is functioning and hooked up correctly. The solenoid bleeds off pressure that opens the wastegate there by increasing boost. You adjust the wastegate accuator by plugging the line going to the solenoid then adjust the rod on the accuator until you get about 11lbs. of boost, then unplug the line and hook to the solenoid as normal. The computer sends a variable duty cycle signal to the solenoid to control boost.

 

[87TTypeKid]

Ok, so this being the case, how can I check what is going on with it? My guess is that if its not working (boost hasn't changed), it is either a) stuck closed, or b) stuck open...if it was stuck open, I'd be overboosting. If it was closed, I dont even know what that would do. Disconnecting it didn't affect boost at all...I still only had 12.5-13 psi.

Id rather not use a manual controller, mainly because they are somewhat unreliable from certain stories I've heard.

Where can I go from here?

 

[turbojd]

Are you sure that the wastegate hose is hooked up correctly with the restrictor in the plastic (Y) the straight hose going to the compressor housing? Check and see if the hoses are dry rotted and leaking too.

 

[mikestertwo]

If it was stuck open you would have low boost, stuck closed and it will over boost. Disconnect the actuator from the wastegate and see if the wastegate moves freely. Then check the length of the actuator rod. To start, it should be about 1/8 inch short in reaching the pin on the wastegate arm. Check all your hoses for cracks, make sure they are plumbed correctly and make sure the hose is on the correct port on the solenoid.

 

[83ttypecooled]

low boost

Hi,
Since your problem seems to mirror the difficulties I experienced with my low boosting TTA, I will give you what turned out to be my solutions. First, and foremost, my turbo hoses were reversed; the Y has an orifice in it, or should. If your Y does not, then you are going to have low boost. My hoses were also backwards, For a proper diagram, go to GNTTYPE.org . Last, but not least, I replaced the boost solenoid. At $25, you can't go wrong with that insurance. End result? All the 16.5 pounds of boost the car was designed to deliver, and it runs VERY strong. Good luck!

 

[Quick6'n'-K.C.]

On your factory solenoid, make sure the vent to atmosphere tit is open, and doesnt have a cap on it...

Here is a picture of how the y is supposed to go.

 

[Lee_Burough]

I didn't notice any appreciable change in boost with the Thrasher chip (one of the chips with 'added boost') either. The only time I recorded a change in boost was by changing the wastegate rod length and using a manual boost controller.

Get a chip with the right programming (that means a modern chip), a manual boost controller, and a Heavy duty wastegate, and you'll be set to go.

Added: Here is another picture about the "Y" fitting:

 

[garrett]

In the picture offered by Bryan, the "Bleeder" he is refering to is the wastegate selenoid? And then a vacuum line runs from the selenoid to the vacuum block? Is this a correct interpretation?

 

[Quick6'n'-K.C.]

In the picture offered by Bryan, the "Bleeder" he is refering to is the wastegate selenoid? And then a vacuum line runs from the selenoid to the vacuum block? Is this a correct interpretation?

Correct, Bleeder is what i meant by either manual bleeder, or the factory bleeder (wastegate solenoid)

The vacuum line runs from the wastegate solenoid to that y fitting.

From the factory, there is a 90° elbow fitting that will reduce the hose size from the 7/32 down to 1/8th inch.

I have parts layed out and can take pictures if you want.
BW

 

[garrett]

That would be helpful to alot of us, thanks.

 

[scottyb]

If it was stuck open you would have low boost, stuck closed and it will over boost.

Other way around. Open would overboost.

 

[mikestertwo]

I was referring to the wastegate, not the solenoid.

 

[87TTypeKid]

Thanks for all of the input, everyone! I came to find out the solenoid was working properly, and I just had the two vacuum lines reversed on the turbo. I didn't realize one port had the restrictor, so when I switched it, the boost went right up to 16-17 psi where its supposed to be with the chip!

The car got ungodly quick...i like this.

Sorry for those running 10s-11s....I used to have an IROC-Z that went 14.60, so a car thats over a second quicker feels really fast to me.

 

[jm87GN]

Overboosting

I am having trouble with overboosting. I have a HD actuator and a Boost Command boost controller, however there seems to be no effect whether you adjust the rod all the way out or play with the boost controller. Can someone help me out? I was not the person who did the installation so, I am not so sure what may be wrong.

I have attached a picture of the "Y" and the vacuum hoses that go to the actuator and the compressor housing. However the end that is supposed to go to the selenoid is blocked off with a screw and wire tie. What effect does this have? I am lost Also, what does the selenoid look like? Anyone have a pic?

 

[Quick6'n'-K.C.]

The solenoid appears to be located right below your left hand there, that red wire attached to the red double male connector plugs into the solenoid.

The hose in your hand, that is supposed to plug into this....

This is the solenoid.

For the boost commander to work, it must have a hose from the Y fitting..

I cant see below your hand, is there anything plugged into the red connector?
BW

 

[Quick6'n'-K.C.]

PS

Once you get the hose connected correctly.

Turn the key on and dont start the car, you need to varify the controller works.

Make sure the controller is ON, then turn the dial up to about 3/4 floor the car and the red light should illuminate, and you SHOULD hear a BUZZ under the hood..
That would be the solenoid humming and letting you know that its working.

If it doesnt work, turn the knob all the way up and see if you can get the solenoid to buzz.
Once you get the controller to work, turn the dial back down to 1/2 or less and see where the boost is at.

I have that controller in my daily driver...

BW

 

[jm87GN]

I took the bolt out of the end of the vacum line and attached it to the wastegate selenoid. However I do not see that any vacuum lines come from the boost controller. How does the boost controller tap into the "Y" fitting? All I see coming from the boost controller are electrical wires.

Anyhow, I did turn the boost controller 3/4 and floored the gas. The red light did illuminate, but the selenoid did not buzz at all. I then turned the boost controller all the way up, and the light came on again, however again no buzz. I then decided to back it all the way down and try. That's when I heard the buzz. It buzzed until I went to half way. Right before half way the buzz goes away. Is something wrong?

 

[Quick6'n'-K.C.]

I havent had to mess with my controller for awhile, so my memory must be off.

The controller is wired into the ECM, so it appears to be working if you were able to hear the solenoid buzz.
I was thinking it had to be turned past 12 oclock...

The boost commander controls that little solenoid to control boost.

I would make sure the boost is low, how low of boost are you looking for?

BW

 

[jm87GN]

I would be comfortable wit stock boost at this point. Or even 16-18. I just took it out for a test spin with the Boost commander on, and it did absolutely nothing.

The boost was climbing up in the neighborhood of 25# And the knob was barely past 1/4 turn..