What is this conector ?

[njbadboy]

I was washing my car today and when I opened the hood to wipe off the motor. I found a connector that was unplugged. I plugged it in to the other end but did not notice any difference. Who knows what this does? It has a red male plug into female plug and the vacuum hose that that is split into 3 and one end goes to the waste gate actuator. There is a little bracket that this connector is mounted to with a hole on one end that obviously should have a bolt that secures it some ware? There is a short vacuum hose that sticks out about 2 inches and it has a screw in the end. I will bring home my digital camera tomorrow and take a picture of it and post it here, but if anyone knows what this is and what it does I would appreciate it.

Thanks

Dave

 

[VadersV6]

Sounds like the wastegate solenoid. The top front valve cover bolt is a studded type, and the solenoid bracket gets dropped on that stud and then locked down with a nut. The computer cant control boost without it. But there are other ways to get the boost you want. Mine isnt plugged in, or actually even on the car. Some people get a code without it but I havent had any issues. I use a modified air pressure regulator to control my boost. You can also plumb the vacuum line going straight from the compressor to the wastegate diaphragm, and then use an adjustable wastegate arm to control boost. This is called "tuner" style, but spoolup is dog slow....I mean...SLOW!
If the wastegate arm is adjusted properly and you have the wastegate all hosed up correct with the wastegate solenoid plugged in, you will get the exact boost level that the computer tells it to get. With my setup, the turbo spools so much faster than with the solenoid controlling it, its ridiculous. Plus I hardly have to have any tension on the wastegate arm to get the boost I want. Tuner style, it takes ALOT of tension to get any useful boost on my car. Mine is only maybe 3 turns past the zero tension spot and I get 20psi like that.

 

[njbadboy]

Thanks Vader. My spool up is dog slow and burbles a bit and even sometimes sputters like an engine miss until the boost seems to blow it out to run clean. The motor seems way to unresponsive and it stumbles a lot. I remember these cars being more crisp and responsive. I thought maybe my thrasher chip is part to blame? I ordered a new EPROM chip from Eric @ TT . We will see after I get it and install it. Any thoughts on why this was disconnected? The car has an adjustable waste gate that is adjusted manually by threading the rod in or out. I remember my friends 86 T type had a bleeder type valve that bled off vacuum from the waste gate actuator to control the boost. I don’t remember how the throttle response was but mine sucks. It feels like a clogged vacuum that when the boost builds above 8 to 10 lbs it finally blows out all of the loaded up fuel to finally rush on surge of power but this feels so un smooth and brash. HELP

Dave

 

[VadersV6]

Thanks Vader. My spool up is dog slow and burbles a bit and even sometimes sputters like an engine miss until the boost seems to blow it out to run clean. The motor seems way to unresponsive and it stumbles a lot. I remember these cars being more crisp and responsive. I thought maybe my thrasher chip is part to blame? I ordered a new EPROM chip from Eric @ TT . We will see after I get it and install it. Any thoughts on why this was disconnected? The car has an adjustable waste gate that is adjusted manually by threading the rod in or out. I remember my friends 86 T type had a bleeder type valve that bled off vacuum from the waste gate actuator to control the boost. I don’t remember how the throttle response was but mine sucks. It feels like a clogged vacuum that when the boost builds above 8 to 10 lbs it finally blows out all of the loaded up fuel to finally rush on surge of power but this feels so un smooth and brash. HELP

Dave

The wastegate arm is only part of the adjustment. Something needs to bleed off air, whether it be an aftermarket bleeder of some type or the factory solenoid which is a computer controlled bleeder. How is your system plumbed up? Explain it in complete detail, starting from the hose coming off of the compressor.

 

[njbadboy]

Vader. After looking things over it seems like it is plumed bone stock. I do not know if the guy I bought the car from purposely unplugged the solenoid or it just came unplugged on its own but he installed aftermarket valve covers which are really sharp check out the slide show of my car and you can see the Buick black and brushed aluminum valve covers. Daves 87 GN
Any way if the solenoid mounted to the factory valve cover with a stud that would explain why it was not bolted to anything. That will be an easy fix. I can find a neat place to bolt it to. As far as adjusting the waste gate to produce more boost I am a big fan of using the bleed off type system over an adjustable arm. the adjustable arm method bleeds off exhaust pressure before the boost builds so there is much more lag and than when the boost comes on you cant really play with the throttle to control the boost real well. It seems to rush on almost full boost so it is slow to build and then when it comes in it rushes right to max boost pressure. Not very street friendly. I guess for the 1/4 mile it works OK but around town it is not very friendly. What I don’t know is will the computer control the boost with the solenoid connected or can you still bleed off vacuum with the solenoid connected. I am sure with the aftermarket chip it tells the computer to produce more boost so I don’t quite know why you would need to bleed off vacuum if the chip can tell the computer to produce a specified amount of boost pressure? Cant you either use 1 or the other? Why do you need to bleed off vacuum or use an adjustable waste gate rod if the computer can control the boost? Thanks for your help Vader.

 

[VadersV6]

A bleeder vs. a wastegate adjustment isnt really a comparison cause they work together. Ive tried a tight wastegate and a loose one with the pressure regulator and i prefer a loose wastegate because the bleeder is bleeding off so much air at low rpms that even though the wastegate tension is small, there isnt enough air in the system to really move it open until higher boost/airflow levels. Mine is only 3-4 turns past the closed puck position so there isnt alot of tension. Boost is easily controlled with the throttle but it is alot more sensitive than stock. i can get full boost with 2/3rds throttle but its still not like an on/off switch. It seems to slowly move the puck open below 1/2 throttle for quick spool, but then slams it open above 1/2 throttle, so I get no boost spiking or creep at all. If you want to hook the solenoid back up, do it, and turn the wastegate arm until you reach stock boost. From there on, write down how many turns of the arm it takes to get an extra 1psi. Garrett designed the turbos to get another 1 psi with each turn...or close to it. If it doesnt, there is another variable affecting it. But the factory solenoid boosts slow, and tuner style is even slower...alot slower on my car. The pressure regulator, set to bleed off alot of air at low rpms and less air at higher ones...not linear, (what mine does because its a very small regulator designed for controlling small amounts of airflow) with light wastegate arm tension gives really quick spooling for me, and I get about 2-3psi for every turn of the wastegate arm. I was messing with different setups for controlling boost, and Ive ended up really happy with what I have now.