weird overboost prob!

[ABLITZ]

ok i got ALL the vac lines off the wastegate and it overboosted .i know its overboostin cause it will cut out and buck.
wth could cause this?isnt supposed to only make 8#'s with the vac lines off??
TIA!


btw gonna go out and clean the air filter to see if it helps

 

[Coloty]

Not sure on this...........I know if I remove the hose on the wastegate solenoid that goes to the actuator I get lots of boost 22-23 lbs or so. If I leave that one on and disconnect the vac line from the solenoid to the compressor housing on the turbo I only get 8 lbs or so.

 

[ABLITZ]

i have both of those disconnected.gonna hook back up the one from the solenoid to the actuator and see what happens.thanks for the help/info!

 

[Coloty]

let me know for sure.......maybe my configuration is wrong?? Maybe I have them reversed or something. Who knows what I did one night in a half toasted state. I have a TE-44 with an upgraded actuator so it is not stock.

 

[smeagol]

If you have all of your vacuum lines off, otherwise what will actuate your wastegate? Nothing.

Keep all vacuum lines connected, unplug the electrical solenoid on top of the turbo. You should have base boost if you do this.

 

[Coloty]

Base boost is defined as what? 8 PSI or 14.7 PSI I have always wonder this question. I assume by disconneting the vac line from the solenoid to the actuator......no boost is bled off....thus more boost. Is this correct Brian?

 

[ABLITZ]

hooked up both lines and its workin .no more overboost...didnt know you could disconnect the electrical solenoid and get base boost.thank you all for the help!

 

[kwick6]

Base boost is defined as what? 8 PSI or 14.7 PSI I have always wonder this question. I assume by disconneting the vac line from the solenoid to the actuator......no boost is bled off....thus more boost. Is this correct Brian?

No, you will get more boost when the solenoid is "bleeding off the boost"
It is bleeding off so that not all the boost is sent to the actuator can. If you unplug the solenoid then all the boost will go to the can and you will find base boost.

Not sure what actuator you are using. I have a TE44 also, and mine is a 10psi base boost. Just unplug the solenoid and drive the truck, you will find out what the base boost is. I am in the process of upgrading my actuator because on warmer days I can only get about 12-13 psi with this actuator... thats using an ANS controller turned all the way up.

Later,
Scott

 

[AlaskaTy]

Let me get this clear...if you remove the vac line from the solenoid to the WG actuator you get more boost right? Are we talking more boost as in BAD boost (boost that'll cost you 2k in engine work) or is it GOOD boost that'll shave time off your ET.

Jason

 

[TurboTony]

The first type....

If you don't give the actuator a boost "signal" as in anything at all the spring in the actuator will hold the w/g closed forever. Thats a really bad thing BTW.

The purpose of the w/g solenoid is to bled a bit of this boost pressure that the actuator would normally see off to atmosphere. Thats how the ecm raises/lowers boost.

The boost "signal" that the actuator see's works against its spring to open the w/g itself. So if some of the signal is lost(bled off) the spring becomes effectively stronger and more boost is produced.

Make sense?

The point of all this is NEVER EVER DISCONNECT THE LINES FOR THE ACTUATOR


Tony

 

[AlaskaTy]

Holy crap! Thanks for the info Tony. It's good to know what you do to destroy an engine...and then stay the hell away from it.

Jason

 

[MR_MNZTR_SY]

ok, wait so overboosting causes early cut-out and jerking and bucking? i thought my wastegate was just kinda opening early cuz it was broke or something. btw, i can only hit like 8 psi. how can i test things withOUT destroying the motor and is the only solution to replace the actuator?

 

[GM TURBO]

Overboosting will set a code. Jerking and bucking is caused by ignition problems - if I were a betting man. 8# of boost could be knock reduced or could be a bad WG solenoid.

 

[MR_MNZTR_SY]

when its jerking and stuff, the tach seems to stay pretty smooth. ive only done it a few times, id prefer not to seriously damage anything. i have no codes, and i am kinda set on a bad wastegate solenoid. i also have this irritating miss that i just cannot get rid of. yes thats the ignition problem right there, but im leaning towards the fact that i have more than one problem :roll: