low boost / loud spool / no boost leaks, wtf!

w1kk3d · Apr 1, 2005

(2g TSi AWD A/T - 16g, ported, 34mm wg, all hard IC piping, intake, type-s vented(yea yea), o2 dump, 2.5" dp to full 3" apexi n1, mbc, safc)

Ok, I'm at a loss already

Here's what is happening:

- Wants to die when first starting up in the morning, unless I raise the LowThrottle 1k setting to +10. I can lower it back to 0 when its been running for a minute or 2.

- Doesn't really want to go when boosting, loud spoolup, only hits a max of 10psi. It runs just fine when it's in vac.

- Did a boost leak test with a huge compressor, the boost gauge doesn't even move, and I can't hear *anything* leaking, not even from the mbc bleeder hole. No air coming out of the exhaust either. I know the tester works, because it found a TB leak on my brothers car just minutes afterward.

- The wastegate arm did not move on my car when doing leak test, opened on my brothers just fine. I can pull it open with my hand, but it takes alot of strength.

- Did a compression test, 190-185-180-185

- New spark plugs gapped at .28, then tried .32.

[misc.]

- 1 manifold stud snapped off in head, top right. Been like that for months.

- o2/dp gasket probably shot, i can feel exhaust putt-putt out of it while idling, but that also has been like that for quite a while.

- Keep getting P1500 code for Alternator Terminal Circuit... but I think it's because the ghetto rigged o2 dump tube (exhaust flex pipe clamped on for extension) is very close to alternator, and almost melted the wiring until i gobbed some copper rtv on it and it's held up fine. It charges fine, never dims, etc.

[Things left to look at]

- pressurize wg nipple directly to see if wg arm opens.
- check ecu?
- ???

ANY suggestions?

greenstreak · Apr 1, 2005

If your wastegate arm wasn't opening you would have uncontrollably high boost, not the opposite.

If you are seeing no reading on your boost gauge at all you must have a giant leak somewhere. Big enough that it isn't hissing out....it is just gushing out.

w1kk3d · Apr 1, 2005

greenstreak said:
If your wastegate arm wasn't opening you would have uncontrollably high boost, not the opposite.

If you are seeing no reading on your boost gauge at all you must have a giant leak somewhere. Big enough that it isn't hissing out....it is just gushing out.

well i meant stuck open...yanno, it's hard to explain when you can "open" it by hand, when it's really closed...or whatever

lol

If i did have a huge gushing leak...wouldn't I be able to hear it? I get nothin.

I'm going to try pressurizing the wastegate nipple and various other areas (smic/tb elbow) and putting the dump tube back on...fun fun!

DR.Spock · Apr 1, 2005

if you take the intercooler pipe of the throttle body and seal it then hook the boost leak tester up to the compressor and see if the air is leaking from the IC pipes. just work and test your whole intake systems in sections. it might help with locating where your losing pressure from.

Turbocharged · Apr 1, 2005

DR.Spock said:
if you take the intercooler pipe of the throttle body and seal it then hook the boost leak tester up to the compressor and see if the air is leaking from the IC pipes. just work and test your whole intake systems in sections. it might help with locating where your losing pressure from.

Thats exactly what you need to do. You OBVIOUSLY have a big boost leak.

w1kk3d · Apr 4, 2005

Welp, when I had the sidemount off I was trying to pull the licp from off the j-pipe to check the couplers, when I noticed this: [1.6mb]
http://www.wikked.com/talon2/thinkifoundtheboostleak.mpg
For those too lazy to d/l, I could move my j-pipe side to side... the
allen bolts were also turnable by hand! wtf...I tightened them both 2½
turns...oof. See, the licp fitment is *so* tight with the sidemount on,
that I didn't notice it the other day.

I couldn't change the fuel filter... who designed that shit?

I got the top fitting off easily, but the bottom one?

Impossible.
Even with the battery/tray/thing under the tray off, I got a wrench on the bottom fitting, blindly, and there's zero leverage at that point.
Ah well. It runs like a raped ape, I'm happy

btw, Seafoam + Restore = brand new car... wow.

Gringoloco · Apr 5, 2005

If your wastegate arm wasn't opening you would have uncontrollably high boost, not the opposite.

I thought if your wastegate wasnt opening you wont get any boost at all. Doesnt the wastegate have to open inorder for the car to build. Ive seen people run into problems with the wastegate not opening all the way so they couldnt build full boost. Dont take this the wrong way im just trying to learn here. But how if the wastegate is not opening would you get uncontrollable boost building, like running open wastegate (with no boost controller)? Im having a problem with my boost controller at the moment, its brand new. I have everything installed properly, but it doesnt hold a steady line of boost. I have backed the screw all the way out, and still over 20 psi it goes. I pulled the whole thing apart and everything looks good, but im thinking its a faulty controller. Im trying out one of my friends controllers off his car tomorrow to see if its the controller or something else. But when I saw your post it has me curious now.

diambo4life · Apr 5, 2005

Gringoloco said:
I thought if your wastegate wasnt opening you wont get any boost at all. Doesnt the wastegate have to open inorder for the car to build. Ive seen people run into problems with the wastegate not opening all the way so they couldnt build full boost. Dont take this the wrong way im just trying to learn here. But how if the wastegate is not opening would you get uncontrollable boost building, like running open wastegate (with no boost controller)? Im having a problem with my boost controller at the moment, its brand new. I have everything installed properly, but it doesnt hold a steady line of boost. I have backed the screw all the way out, and still over 20 psi it goes. I pulled the whole thing apart and everything looks good, but im thinking its a faulty controller. Im trying out one of my friends controllers off his car tomorrow to see if its the controller or something else. But when I saw your post it has me curious now.

The WG actuator opens the flapper door when it gets the appropriate boost signal. By opening the flapper door, exhaust gases bypass the turbine hence regulating boost pressure. If the WG actuator doesn't move at all (ie. flapper door remains shut,) all the exhaust gases will flow through the turbine wheel causing the car to build boost which will create more exhaust energy which will cause it to make more boost and the vicious cycle continues. It will just creep and creep till you let go off the gas pedal or pop the motor whichever comes first.

Your problem seems like a boost controller issue or faulty actuator if you have an IWG turbo.

Gringoloco · Apr 5, 2005

Your problem seems like a boost controller issue or faulty actuator if you have an IWG turbo.

My turbo has 200 miles on it. I hooked up the iwg nipple to a air tank and turned on the air, it doesnt move. I unbolted the 2 bolts holding the wastegate on and I can move the arm and the flapper open and shuts. Put the two bolts back on, and it doesnt move again. Does this mean the waste gate is bad? Man I swear if I have another broken part on a new piece, im getting so mad at this car right now

diambo4life · Apr 5, 2005

Hook up the IWG actuator hose directly to the intake manifold (boost signal source) with NO MBC and see what happens. If it holds boost fine (IWG actuator spring,) then the actuator is ok. If the boost creeps like crazy or doesn't hold the minimum boost as per the actuator spring, the actuator is most likely faulty.

91bluetalon · Apr 5, 2005

my friends car did the same thing. but made no noise at all. no spooling, nothing. i replaced the wastegate and all the normal sounds came back, spooling, intake,bov,etc. car still wasnt the same. checked for boost leaks and what do you know. every weld on the custom piping was leaking. so yea check for leaks. the tinyest leak will hurt the performance.

greenstreak · Apr 5, 2005

Gringoloco said:
My turbo has 200 miles on it. I hooked up the iwg nipple to a air tank and turned on the air, it doesnt move. I unbolted the 2 bolts holding the wastegate on and I can move the arm and the flapper open and shuts. Put the two bolts back on, and it doesnt move again. Does this mean the waste gate is bad? Man I swear if I have another broken part on a new piece, im getting so mad at this car right now

Diambo explained the wastegate operation correctly.

This to me sounds like a bad wastegate actuator. If you hit the actuator with over 15 psi and it didn't open the flapper it is bad.

greenstreak · Apr 5, 2005

91bluetalon said:
my friends car did the same thing. but made no noise at all. no spooling, nothing. i replaced the wastegate and all the normal sounds came back, spooling, intake,bov,etc. car still wasnt the same. checked for boost leaks and what do you know. every weld on the custom piping was leaking. so yea check for leaks. the tinyest leak will hurt the performance.

He has already found the problem. Look a few posts up.

low boost / loud spool / no boost leaks, wtf!

w1kk3d

greenstreak

w1kk3d

DR.Spock

Turbocharged

w1kk3d

Gringoloco

diambo4life

Gringoloco

diambo4life

91bluetalon

greenstreak

greenstreak

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