7mgte not boosting?

[Push]

So I have issues with my car... Car would only boost after 3000-3500 rpm, it boosted well and pulled quite hard. A couple days after a decent pull, the car did not want to boost anymore... Strange... Factory boost gauge does not move at all, just stays under vacuum. A day goes by, and the car acts normal again and boosts just fine... Yet the next day, car does not want to boost at all again... Today I did a boost leak test, and found no leaks... Car runs and idles perfect, no misfiring or anything out of the ordinary. My afm is fine, and no check engine light or codes... I also did check the turbo, no bent fins, no oil burning, turbo still spins freely. I know I am missing something stupid, please enlighten me on what I could of missed, or what the problem might be. Thank you!

 

[Devin LeBlanc]

Its probably just the gauge or the sensor..

 

[Push]

It could be, but the car definitely is not boosting... It will get up to speed, but does not boost...

 

[hvyman]

Are you going off the gauge or going how the car feels?

How did you do the boost leak test?

Its kinda odd that you have boost one day and not another. There has to be a variable. Were the conditions all the same?

Edit: Does it just not go? Do you have codes?

 

[Push]

Yes, it is very weird... It goes up to speed slowly, but smoothly. Boost never comes no matter which gear or rpm... Weather conditions here have been cold in the 20's. I'm thinking maybe I missed a vacumm hose, or something stupid... I'm going to sleep on it and try to look at it again tomorrow...

 

[Push]

[video=youtube;9mGln72NRyc]http://www.youtube.com/watch?v=9mGln72NRyc[/video]
So drove the car tonight, in 5th gear with the pedal down the boost gauge actually registers but still no boost... Is it possible that I have a waste-gate issue? I really doubt I have a bad turbo, but I'm starting to think I do... No oil burning, no death whine, oil pressure is perfect, car runs with no hesitations or misfires. So really leaning toward either the waste-gate, or I hate to say it a bad turbo... I'm going to tear it apart on Tuesday and figure it out...

 

[hvyman]

Ok try making a video with no music and actually showing your problems on the gauges through all gears.

Is it that just when you go wot that you go no where? If so you have a boost leak.

Your descriptions are vague.

 

[Push]

Video I agree is meh... Car does not boost what so ever, doesn't matter which gear, or if its wot or slight throttle. The car still accelerates to speed, but acts like a n/a. I am going to try another boost leak test/tear down soon.

 

[hvyman]

Have you checked codes?

You really are missing all the basics here and giving crap for info.

 

[rayall01]

How about a sticking waste gate. Could do that if it intermittently stuck open. Just a what if, not based on it happening to me or anyone I know, but just throwing it out there.

 

[dmiller]

Do you have any cats? Mine was boosting fine then one day i couldn't even get 2 lbs at all. Come to find out i had a clogged cat. Then i hallowed out the cats and it boost fine now.

 

[89supra7mgte]

If the cats were plugged in most cases the car would run poorly boosted or not.... I would agree with the wastegate. pull the elbow off and if handy grab a vacuum/pressure pump and apply pressure and release see how the flap is working. wastegate opens on pressure. and i know from experience that they can get stuck open (my external one did) also check for any sever cracks around wastegate opening, i have heard of the ct26 gettin extremely hot and cracking around that area...... when cold crack is sealed when running and gets hot crack may expand acting like an open wg.

I know you did boost leak test but also check bypass valve... may also be causing an issue recirculating the boost back into accordion tube....

 

[Push]

So I figured it out... The Turbo that was on the car was not spinning!!!! It was not smoking or doing anything, the car drove and acted like an N/A... I took the accordian pipe off, and sure enough the turbo fins were seized and not moving... I put a new turbo and everything was fine and dandy after that!

 

[Pokey2301]

So what was the reason the turbo seized?

 

[Push]

Good question, it was boosting fine, no smoking and just pretty much failed. I have had turbos failed before by blowing smoke, death whine, etc... This one just died peacefully I guess lol...