No boost...The title says it all

[Heisenberg]

OK - I am going to start a thread - even though I'm sure there have been hundreds of "No Boost" threads. I can't seem to find any that fit my situation.

It all started with one day - normal car - next day - no boost.
Hmmm..

Looked for the obvious.
Lines off, hoses burst, whatever.

1 - I found the cheapy Autozone Rubber "90" I used to go from my MAP sensor to the hardline had a split in it.
Great! Problem solved right?
NOPE - I should be so lucky.
Still no boost

2 - My engine bay is quite well maintained, but what the heck - let's look at the silicone couplers and clamps etc.
I clean and rub on this stuff daily.
All clamps tight as hell.
Silicone couplers - fine
Everything was fine.

3 - Look at every single vacuum line, fitting, and end.
Everything is new silicone and tie wrapped or clamped

Vacuum check = 17 in - OK

4- Remove actuator rod end from downpipe integral wastegate arm -
Check wastegate arm -
A little squeaky -
PB Blaster and it moves freely.

5 - Rig up a blow gun set for 20 PSI and check actuator.
Now I'm finding things.
Air blowing like crazy from around the actuator nipple where my silicone line attaches - had no clamp or tie wrap. My bad.
Can't finish that since I notice how badly the aftermarket heater coolant line "S" hose was pressing up against the actuator vacuum (pressure) line.
So replace the oversized "S" hose with the proper one and it now has adequate clearance for the actuator line to not be molested.
Clamp the actuator line - repeat air blow gun test - actuator moves well. As it should.

6 - Now notice the actuator bracket wiggles.
The two bolts that are holding it to the turbo compressor body are all of about 1/2" long, and if you add the heavy 1/8" thickness for the actuator bracket, not hardly adequately long enough.
In fact, the lower bolt really was not biting and just spinning.
The turbo drain line is real #@#$(&#$ evil son of a ...if you know what I mean - by keeping me from being able to get that new, slightly longer, lower actuator bracket bolt in there.
I actually had to dent the drain line to be able to do so.
I could have and should have just taken it loose from the underside of the turbo - since that's so much fun.
But Super. Whatever. Done

Find some 3/4" 8mm stainless hex bolts and grind them to about 5/8" long since the turbo compressor threaded holes are blind and the 3/4" long ones bottomed out.
Whatever again - done.

7 - Ok - put it all back together last night - test drive - surely right?
Nope - no boost.

8- Tonight - it's wastegate / puck viewing time.

From what I see - it looks ok.
The puck is attached, and it appears to be ok.
In order to get the downpipe out of my way to look directly into the turbine chamber - I have to loosen the two nuts at the slip fit at the Cat in the AM
Then I will be able to hold a piece of plexi against it and test the puck seating.
But I do not think that is my problem.
I'll suppose I'll do it anyway.
Sort of stinks if that isn't my problem.

9 - At cold (rest) start - my turbine "seems" - how do I say - to be stuck.
A finger push usually requires a little back and forth to make the turbine spin.
Then is spins quite freely.
But there is very little or no end play, and very minimal side to side play
It just on occasion feels "like it is stuck"
**NOTE ** I was only worried about this since a while back I blew out a piece of header gasket and it wedged ever so gingerly in my turbine and I thought - well maybe again.
But at least until I get my downpipe out - the turbine side looks ok with using an inspection mirror.

10 - In my late night poking around - I again find the damned "NEW" replaced Autozone 90 rubber coupler at my MAP sensor to be split.
I use a 90 vs. the stock straight one. Well - at least I try to.
But split Again?
That's a bizarre coincidence.
Even though it's probably not the exact right size at the MAP side nipple - and they are cheap crap.
The reason is I need to find the exact size for the MAP sensor nipple - yet with the right size for my boost hard line.
I realize it might just be pure coincidence that the thing splits so quickly. (since they're cheap crap) - But is it?

11 - *** QUESTION ***
Does the MAP sensor serve any other purpose other than driving the LED Boost Bar graph?
Vortex Buicks say nope. That's it.
True?
Or - to put it another way - would last night's test drive with that broken rubber 90 at the MAP sensor have resulted in no boost?

12 - Currently finishing making a boost tester and will connect it with 20 PSI of shop air to my TA49 inlet bell.
And see if I have overlooked some stupid leak in my intake (Turbo to IC to TB)
No noticeable holes in the InterCooler (Stretch SLIC). I've looked closely at it and it seems A-Ok - Intact.
As I said above - the IC / UpPipe coupler hoses look fine.
But it's possible I haven't noticed a split - and hope the boost tester will prove that.
Do I really have to resort to taking my entire intake system apart and checking each and every component for a leak. I'm kinda of leaning toward no.

13 - *** QUESTION ***
Could I be overlooking a bad modulating solenoid valve?
I thought it would puke a Error Code but maybe only if it is not hooked up it does that.

This system isn't so complicated.
If the turbine spins the compressor, my wastegate and actuator are working, I should be developing boost pressure in my intake.
But - yeah - of course I'm not.

So any ideas would be appreciated.
Cuz I'm not seeing it right now.

This car is not thrashed and trashed - so my head tells me it is something simple.
Very simple.
I just can't find it.
I can't believe how much I'm taking loose and off in trying to hunt this problem.
Help?

 

[RmvBfrFlght]

11 - *** QUESTION ***
Does the MAP sensor serve any other purpose other than driving the LED Boost Bar graph?
Vortex Buicks say nope. That's it.
True?
Or - to put it another way - would last night's test drive with that broken rubber 90 at the MAP sensor have resulted in no boost?

On a stock TB the MAP sensor is only used for the LED boost gauge.

13 - *** QUESTION ***
Could I be overlooking a bad modulating solenoid valve?
I thought it would puke a Error Code but maybe only if it is not hooked up it does that.

If the solenoid stays shut it should at least boost to the spring pressure of the waste gate actuator. This is the same as if the boost pressure line was plumbed directly to the actuator.

RemoveBeforeFlight

 

[earlbrown]

First, I have to say good job on the troubleshooting!

My guess would be that the wastegate puck might have fell off. It's pretty easy to investigate, just pop the downpipe (or elbow) loose and see if you're making a good seal.

If that's not it, and the turbo is moving a good amount of air like normal, you'd have to have a hell of a dump to keep the pressure from hitting the boost gauge sending line. Something like a ruptured intercooler tank or compromised up-pipe.

 

[1fastcobra]

U said the the actuator moves freely. ( easy ) ?
Should be very firm and stiff to pull on
Also u said the turbo wheel gets stuck. !!
It should spin very easy. And be spinning and idel.
U may have a bad turbo and actuator. This will give u no boost

Posted from the TurboBuick.Com mobile app

 

[Heisenberg]

Thanks guys.

Puck? - Is on - Intact.

Actuator - stiff but nothing out of the ordinary

Agreed on the turbo producing boost without a waste gate. Which is why the problem is so hard to diagnosis.
I'm in the process of looking for a simple answer - i.e. the Intake system via a boost test.

 

[John Larkin]

Do you have an air compressor? Hit the turbine wheel with some air from a blow gun. It should spin easily. If not, you probably found the problem.

 

[Heisenberg]

Do you have an air compressor? Hit the turbine wheel with some air from a blow gun. It should spin easily. If not, you probably found the problem.

I do - What self respecting TR collector doesn't have a least one air compressor?
I can use a blow gun with a 6" extension and give it a blast of air on the turbine side.

I wonder what the AVG PSI is on the exhaust / turbine side of things?

But don't get me wrong - it spins pretty easily - with my finger.
I see nothing on either side with either the blades or shaft that leads me to believe I have a turbo problem per se'
It's that "at rest" "cold in the AM" where it seems to be a little "stuck" - and needs a little extra help with my finger. But that might just be normal.
That probably doesn't adequately describe it - but best I can muster.

 

[Heisenberg]

U said the the actuator moves freely. ( easy ) ?
Should be very firm and stiff to pull on
Also u said the turbo wheel gets stuck. !!
It should spin very easy. And be spinning and idel.
U may have a bad turbo and actuator. This will give u no boost

Posted from the TurboBuick.Com mobile app

Turbo Clam and I were talking tonight and tomorrow I'm going to rig up the cold air inlet pipe with the MAF connected - but removed off the inlet bell - just to try not to puke an EC
And fire the engine and see if the turbo spins.
Which it should.
And see what's what.

 

[Heisenberg]

First, I have to say good job on the troubleshooting!

My guess would be that the wastegate puck might have fell off. It's pretty easy to investigate, just pop the downpipe (or elbow) loose and see if you're making a good seal.

If that's not it, and the turbo is moving a good amount of air like normal, you'd have to have a hell of a dump to keep the pressure from hitting the boost gauge sending line. Something like a ruptured intercooler tank or compromised up-pipe.

As I said in my previous post - downpipe is loose and I can peek in.
Puck is intact and looks "OK"
Whatever "Ok" means for this particular style downpipe I have on my car. It has a little wobble joint - but to me - it looks fine.
Inside of turbine housing looks fine as well.
Nothing noticeable or weird looking.

Yeah - and for sure I do not see any sort of massive IC or up pipe breach.
That would be obvious and I'm not seeing it.
So - tomorrow I'm going to see if the ole turbo is spinning when I fire up the engine - with the cold air removed from the inlet bell.

I mean think this way.
One night - great boost.
Park it.
The next day - nada.
To me - that means something simple.

 

[Phoneguy]

I would bet that the "simple" is a new turbo in your future...

Bryan

 

[Heisenberg]

On a stock TB the MAP sensor is only used for the LED boost gauge.



If the solenoid stays shut it should at least boost to the spring pressure of the waste gate actuator. This is the same as if the boost pressure line was plumbed directly to the actuator.

RemoveBeforeFlight

Thanks for taking the time to answer those 2 questions directly.
Appreciated.

So - if the MAP sensor tells the ECM nothing - and is only used for the LED bar graph display
Then...
If the ECM tells the modulating valve to modulate - what tells the ECM to make those decisions?
Or to put it another way - what info or data does the ECM use - to decide to start modulating and venting off pressure from the actuator line - (to atmosphere - right?)

 

[Heisenberg]

I would bet that the "simple" is a new turbo in your future...

Bryan

You're cruel.

But that would suck - since I keep clean oil, there is hardly any play in the shaft, I don't beat the crap out of it - and I keep it really polished!

But I'm not sold yet. The thing spins decently easily with finger touch.
I'll find out in the AM when I puff it with air on the turbine side - and reconnect the downpipe and fire the engine.
Shoulda done that right away.
Duh!!!

 

[Phoneguy]

You're cruel.

But that would suck - since I keep clean oil, there is hardly any play in the shaft, I don't beat the crap out of it - and I keep it really polished!

Could be worse.......

Bryan

 

[earlbrown]

I hate to overstate the obvious but by 'no boost' is there any change it means 'no reading on the boost gauge'?

Does the car pull when you floor it? And what does the turbo whistle sound like during the pull?

 

[Chuck Leeper]

Haven't seen this mentioned: Run the a line directly from the compressor hsg to the w/g actuator.
A stock actuator should give you reasonable boost. [12-14?]. The HD actuator is going to show more... like 18#.
This eliminates the boost control solenoid, ecm control, etc.

 

[TurboDave]

I don't think a faulty solenoid can cause a "no boost" situation. Remember what it's function is: It's function is to raise and control boost over the base spring in the actuator. It does this by bleeding boost away from the actuator. The worst a faulty solenoid could do is not work at all, yielding base boost, or failing open and causing an overboost situation.
A faulty actuator could in theory cause a "no boost" situation if the spring broke allowing very little pressure to open it completely.

There just aren't that many things that can cause a complete "no boost" situation that wouldn't be immediately obvious.

I'm wondering if the boost gauge is not working or not hooked up????

 

[Heisenberg]

Thanks TurboDave and Chuck.

I value you two guys' opinions since I know you've been kicking around the TR world a while.

You guys want to hear an real outrage / knee slapper?

In the WE4 (the car without the boost) - I ..ahh.....(hate to say this)...don't actually have an aftermarket boost gauge.
I rely on the ...uggghh..factory LED bar graph.
Now before everyone starts laughing hysterically, I do have most of the parts (A-pillar pod, gauge, etc) - but was waiting to be able to do it all a the same time with Phantom II gauges.
And I can't find my damned Blue Nylon tubing that I wanted to use - (buried somewhere)
I am a freak when it comes to not doing some thing half-a$$ed and wanting to do it once - right the first time.

Ok - and I had a couple of old gauges with nasty old white nylon tubing that came out of cars I bought - and was getting ready to just slap a temporary one in even it had to dangle - or hang under the windshield wiper temporarily..
But so yesterday, I was browsing Horrible Freight, and saw in the auto section - Combo Vacuum / boost gauge kits
So I bought a Vacuum / Boost Gauge kit for $20.
The whole kit; gauge, tubing, fittings, for $20? If it works - that's a steal.
Now will it be accurate or last more than a day? - (considering Horrible Freight and their less than stellar Made in (Insert Third World Country here) quality - but it's going in this morning.

But to Earlbrown's questions -
1- No; I hear no whistle.
I feel no pushing my a$$ back in the seat action.
No tires squeeling.

2 - Yeah it pulls strong.
I was telling Turboclam that I was pretty impressed with the power of my motor - even without boost.
I felt as if I could run people even without the boost.
Well, not really - but ya know!
No - it pulls decent- but revs higher than normal, and runs out steam pretty quickly.
Sort of like a regular Regal, but with a good motor in it.

I'm hitting it right now in the garage.

I'll keep you posted.

Thanks for the support.

 

[Heisenberg]

I don't think a faulty solenoid can cause a "no boost" situation. Remember what it's function is: It's function is to raise and control boost over the base spring in the actuator. It does this by bleeding boost away from the actuator. The worst a faulty solenoid could do is not work at all, yielding base boost, or failing open and causing an overboost situation.
A faulty actuator could in theory cause a "no boost" situation if the spring broke allowing very little pressure to open it completely.

There just aren't that many things that can cause a complete "no boost" situation that wouldn't be immediately obvious.

I'm wondering if the boost gauge is not working or not hooked up????

Good info on the modulator solenoid Dave.
Thanks - as I suspected how it worked.

The actuator "seems" fine.
By hand pressure, by regulated 20 PSI from a air compressor.

I'm back it again today.
Stay tuned.

 

[Heisenberg]

Haven't seen this mentioned: Run the a line directly from the compressor hsg to the w/g actuator.
A stock actuator should give you reasonable boost. [12-14?]. The HD actuator is going to show more... like 18#.
This eliminates the boost control solenoid, ecm control, etc.

Good idea Chuck.
Thanks for chiming in.
I'll put in on my list of de-bugs if I find the basics like turbo spinning freely are ok this morning.

 

[Heisenberg]

I don't think a faulty solenoid can cause a "no boost" situation. Remember what it's function is: It's function is to raise and control boost over the base spring in the actuator. It does this by bleeding boost away from the actuator. The worst a faulty solenoid could do is not work at all, yielding base boost, or failing open and causing an overboost situation.
A faulty actuator could in theory cause a "no boost" situation if the spring broke allowing very little pressure to open it completely.

There just aren't that many things that can cause a complete "no boost" situation that wouldn't be immediately obvious.

I'm wondering if the boost gauge is not working or not hooked up????

Dave,

What about the answer to this question I had posited earlier?
Just for my own education.
Not that I think ithas any effect on my "no boost" situation.

So - if the MAP sensor tells the ECM nothing - and is only used for the LED bar graph display
Then...
If the ECM tells the modulating valve to modulate - what tells the ECM to make those decisions?
Or to put it another way - what info or data does the ECM use - to decide to start modulating and venting off pressure from the actuator line - (to atmosphere - right?)