WASTEGATE SOLENOID question

bc1025_TurboGN

New Member
Joined
Sep 24, 2005
I looked at the wastegate selenoid and saw that only one of the lines (the outside) was connected. The other was wide open. I saw on Kirban's they sell a filter for that line.

So I plugged the line with a cap and am now able to adj my boost no problem. Never could before. The weird thing is when I went racing saturday it just didn't seem to pull. The best I ran was a 14.066 at 94.68 mph.


It looked as if I was pulling 18lbs of boost and set at postion 4 on my Ultra Chip (22 Deg Ign timing)

I'm going to make a wild assumption here and guess that I shouldn't have plugged that line, but only restricted it.

I could never get the boost below 23 lbs before that and was afraid I would blow something up. The boost adjustment didn't do a thing (inside car)

Thanks for any help, my mechanical knowledge is limited to very basics and understanding.

BC
 
I could never get the boost below 23 lbs before that and was afraid I would blow something up. The boost adjustment didn't do a thing (inside car)

BC

That port on the solenoid is suppose to be open. It controls boost by venting pressure going to the wastegate actuator. Are you using the stock setup or are you using some other boost control?
 
The selenoid is stock, the wastgate itself I'm not sure. It is adjustable that much I know. There is also a rotory adj inside the car.

Did I screw up by plugging it?
 
It won't hurt anything, you just won't be able to build a lot of boost. It sounds like you may not have your wastegate actuator adjusted correctly. What you should do is plug the vent line on the solenoid, then adjust your wastegate actuator so you can only make about 11 pounds of boost at WOT, then remove the plug on the vent port of the wastegate solenoid. Now the chip should be able to control your boost. It sounds like you are running a thumbwheel chip (multiple programs). Who's chip is it?
 
Thanks so much, great information. You are correct, it is the thumbwheel. It's the Caspar Ultra chip. I'm going to do what you suggest tomorrow. I will post the results. Thanks again
 
One question about the actuator. When adjusting it, do you turn the rod so that it gets shorter (inward towards motor) or turn to make it longer (towards the fender) I know this sounds basic, I'm just learning this technical stuff alittle everyday.

Thanks Mikester
 
If you want less boost, you make the rod longer. If you want more boost, you make it shorter. Rule of thumb, 1 full turn equals about 1 lb. of boost.
 
The little plastic tee in the wastegate lines has a restrictor in it. The restrictor plus the wastegate solenoid are used to the drop the pressure in the line going into the wastegate actuator.

Example, if you are running 20 psi boost, then you have 20 psi in the line going to the tee. The wastegate solenoid lets a little air out of the hoses, so the actuator might only see 10 or 15 psi. That makes the actuator move less, which lets the boost stay up there at the higher pressure.

When you blocked the port on the wastegate solenoid you kept it from bleeding air out of that hose, so the actuator sees the full pressure that the turbo is making. That pushes the actuator open more, which then results in a lower boost level.

Hope that's clear...

When you make the rod longer it essentially means the wastegate will open more for a given amount of pressure applied to it. More open = lower boost. If you are trying to run more boost, you then have 2 ways to do it. You can shorten the rod, so the wastegate won't open as far. You can also have the wastegate solenoid pulse more, which lets more air out of the line, which drops the pressure the actuator sees, which then won't push open as far. But to do that you've got to do some chip reprogramming...

And of course there are other ways to do it, but I won't muddy the waters any more than they already are.

Hope that helps

John
 
Do you have a scan tool? I noticed you said the car felt flat. This could be do to detonation and without a scan tool you won't know. Until you pop a head gasket that is. I guess what I'm saying is if you do great. If you don't then you should turn down the boost and get one. james
 
No I don't have a scan tool. I would like to, but I can't afford one right now. I'm saving for Alky Injection and a larger intercooler. I have to be very thrifty with my spending. I'm having a real hard time convining my ol lady to let me keep this car.

Thanks for all the help
 
Well, I hate to be the bearer of bad news, but if you try to mod the engine and run higher performance levels without some way to make sure everything is right then odds are you won't have a running car for very long.

I know all about saving for parts but you've got to have you ducks in a row. If it was me I'd get a scan tool. Tune the car and then get alky, and maybe some injectors and a chip with the money you would have spent on the intercooler and just mod the intercooler with a dutt neck.

Do some reading before making mod decisions. Pay attention to the guys with fast cars. Lot's of guys have gone fast with almost nothing but a scan tool. Lot's of guys with big parts going slow for what they have.

I don't mean to preach but these cars rock and I'd hate to see you have a bad experience and never really get to enjoy it first. HTH james
 
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