20psi to 22psi caused boost to go away

[shadowdude]

How hard can it be to get a dodge shadow to run with out stupid constant weird problems....Well the new problem is this.car was 20psi..running fine,beside the earlier noise deal i posted.So at 20psi now it ran and boosted fine.Had to put a bleed in the with the grainger valve and tighten the GV all the way in to get 20psi.With out the bleed it would not go to 20psi.So yesterday i decided to go to 25 ...well got it to barely 22 and gave it 3 15 second WOT runs and then it felt like a hose came off, boost drops right off.Nope checked all the piping and nothing.So took vacuum line off waste gate can and it still will not boost at all,not even a pound.When i floor it it sounds like the turbo is spooling a bit cause i can hear the whistle if you will but at the same time it makes a sound like it is backing up in its pressure or pushing out some where.Thing of it is i took the pipe right off at the out let on the turbo and you can still here that odd sound ,like a half dead horn if that makes sense.The turbo is a still very new Enforcer 2 and i checked the shaft play and it spins great and is very tight,well play wise.So can a can go bad from increasing the boost? Even if the can is bad ,wouldn,t you still get some boost ? What the #%^&^%$ is wrong with this car?? so so close to selling it.Oh and the can is the bigger one of the turbo 2, like new and off a daytona 1989 shelby

[x.Gen]

make sure the clip didn't pop off the wastegate arm at the swingvalve.

[shadowdude]

Yep ,checked that it was on,then actually took the can right off to have a good look.I used my compressor set at 10psi and if i put a full 10 into the can momentarily, it moved and pushed out .I have to pull hard on the rod with some force ,so i would think it to be ok.To be honest i never saw a bad can so i am thinking if it takes that bit of force with me to pull it out it should be ok.Never a easy fix ,as always.Hey any one want to buy the car ??

[shackwrrr]

check your blow off valve to make sure that didnt mess up. If the vac line blew off it would not boost either that or the diaphram blew

[x.Gen]

hmmmm....stage I wheel? sell me that enforcer.

if you think you hear boost leaking, and there are no leaks on the cold side, check the bolts on the turbine at the flange. they are a real serious PIA to torque down while on the car. believe it or not, one loose bolt will eventually vibrate the others loose enough to cause the leak; this could also be caused by a warped flange surface.

[shadowdude]

If i sell ,it is the whole car as i am very tired of wrenching on it so even taking parts off would not be an option..sigh..hard to understand i guess but believe me it is a long story.Anyways ,yes i did check the v brackets and other on the turbo ,hell i even checked all bolts attached to it .Found none loose. What i dont get is why did it boost just fine at 20psi and just by a simple 2 psi increase it now wont boost at all ?

[x.Gen]

was only kidding about the enforcer...kinda

I meant the nuts (shouldn't have said bolts) on the turbine to manifold flange, just to be clear. should still produce boost if the puck is closed and there are no leaks before the turbo, even if you had no downpipe on it.

20 psi is enough to start throwing gremlins in your path, even with a nice parts list, the smallest thing can cause problems. if the wastegate actuator were "weak", you'd find out by shimming it. can't do more than throw out a couple common items without looking at it, and you can see how this stuff will make you want to give up (don't do that). stick with it, but keep your head cool. I've missed simple stuff just from being aggravated when wrenching, best thing I can tell you.

[shelbymonster]

reset you computer and try again

[shelbymonster]

did you tried to boost without the vac on the wg can ?

[shadowdude]

All is good x.gen ,i knew it was a light comment lol.I had to step away from the garage because i was getting pretty flip-pen mad and tools where starting to fly.Yes one doesn,t think clearly while like that.So you spoke of waste gate shimming ,and i thought the same as the next step tomorrow.Here is my thoughts.I am going to go tomorrow with out the can on the turbo ,get the swing valve close or locked shut with bail wire or something and very briefly try it once just to see if the boost shoots up.If this works which in hope it does then this would suggest the can is A: weak ,so i,l shim it or B: if it doesn,t work the swing valve puck is damaged and in that case i will have to drop the down pipe and look up in the turbo and see if it is ok.I am hoping for A because i can shim or replace the can easier then taking the turbo off and replacing the swing valve.I just want 25psi and i am done ,tens year later and ,as other can relate ,i am still fighting.Makes it some friggen hard some days.Thanks guys ,i will post tomorrow with results wish me luck.

[shadowdude]

did you tried to boost without the vac on the wg can ?

yes sir...still no boost

[shadowdude]

reset you computer and try again

Never tried that ,but what your theory behind that ? No meanness meant just actually curious and may learn to why that would possibly solve it...

[GLHSBRANT]

try regapping spark plugs to .028. higher boost pressure blows spark out.

[Jeff S]

Never tried that ,but what your theory behind that ? No meanness meant just actually curious and may learn to why that would possibly solve it...

Computer is still programmed to 20lbs of boost, if it notices something different(too much boost that may damage something) it may put itself into a form of turbo limp-mode to keep the turbo from getting damaged(not sure how it would do this, arent turbos all mechanical? I know NOTHING about turbos)...not sure if this is even a valid theory, but cars tend to do some crazy things.

and as x.Gen said, dont give up, and walk away if you get too frustrated...I know Ive fought with problems for 3 hours, get so frustrated I give up for the night, go back out the next day and BOOM, problem fixed in 5 minutes.

[x.Gen]

resetting the computer only works if you are using the solenoid to control boost - if you are using a g-valve, it is irrelevant (no computer control of wastegate).

make this easy on yourself and just jam a couple washers behind the wastegate actuator bracket, then crank it down. two should be enough on each side. if you're lucky you can do it with the actuator still attached at the puck arm. that will be a LOT easier than wrapping wire or whatever around it. this will do two things - raise the min boost level (no vac to actuator), and raise max boost (vac to actuator, g-valve or computer controlled). second, you won't have to do it twice if it works. most importantly, you won't get huge boost spike, detonation, and a cracked piston, etc.

you'll get a handle on it quicker this way, gotta keep thinking simple on this one.

[Jeff S]

resetting the computer only works if you are using the solenoid to control boost - if you are using a g-valve, it is irrelevant (no computer control of wastegate).

Thanks for the info, Im still learning about these cars...and theres a LOT to learn Ive seen by reading this forum

[Vigo]

I like the idea he already posted about wiring the wastegate puck arm in the closed position and seeing if it makes boost. If it doesnt boost that way, you either have a huge leak before the turbine or massive damage to one of the wheels.

[x.Gen]

I like the idea he already posted about wiring the wastegate puck arm in the closed position and seeing if it makes boost. If it doesnt boost that way, you either have a huge leak before the turbine or massive damage to one of the wheels.

admit it, you guys are trying to get him to blow it up. come on.

[butchsuppe]

Check to see if the turbo froze up.

[prepared]

Well, there is some good info here and there is some uh... less than good info here.

1.) It was boosting to 20 just fine.

2.) It suddenly stopped all boost

3.) There is no boost with the vacuum to the wastegate actuator unplugged.


There are ONLY two problems you could have:

1.) The turbo is not creating pressurized air

or

2.) The pressurized air is going somewhere.


Before you go wiring things shut or resetting computers ...

Pull the hoses off the cold side of the turbo. With the engine idling, is the turbo spinning? Use a mirror and flashlight if you have to do NOT stick your finger in there!

Have a friend brake boost it while you feel the outlet of the turbo. Is there air rushing out?

Remove ALL IC piping and reinstall it. Believe me. Many times I have had an IC hose disconnected and didn't see it.

After that, if all has checked out good so far and you still have no boost, you may have to drop the down pipe and see if the waste gate puck is still there.