Rpeck

Okay, yesterday I passed smog on my rebuild motor, I have about 1000 miles on it now. I have a BNR stage 3 Hybrid Turbo .. I did not want to hit boost with my stock BOV, intake and all the stock stuff installed so I never really tried to boost during the first 1000 miles of my break in. But after passing smog yesterday I installed my 720cc primary injectors, I have 1000cc secondaries already installed, I installed my Turbo XS BOV, I installed my cone filter and new TID, I installed my performace chicp in my ECU .. I have all my after market gear on the car now except my Exshaust is still stock (getting that installed on Tuesday) I just finished putting everything back together and I have NO boost!!

I hop in the car it starts right up .. I get it nice and warm and start off at a slow pace .. I go about 10 miles and decide to open it up a little… I hit WOT and let it rev to about 5.5k, The stock boost guage went almost up to ~0~ but I never did get ANY positive pressure! What the hell could be going on? I tried the same thing in 3rd and 4th gear … it is not the guage I know .. cause I don’t hear, and certainly don’t feel the turbo at all! (this car is slower than my N/A at this point) I do not have my boost controller installed yet .. cause until I get another 1000 miles I don’t really want to go over stock boost levels. But I should at least get some positive boost … and at least! 4-6 PSI .. but I am getting nothing! What now? Help!

Thanks a lot,

Robert

GTR

iTrader: (6)

check your vaccum lines. when i installed my boost gauge like a year ago, i had the same problems. check your vaccums. probably just a loost vaccum.

Rpeck

I have double checked .. tripple checked and reinstalled everything 12 times over, there is nothign loose that i can tell .. what particulaar lines would cause me a problem? Plus .. it idles perfect .. and runs perfect .. infact it passes somg yesterday! if there was a vacuum line issue I would think I would have problems with it running right.

Help!

Rpeck

Okay, i just read about 40 posts with the word "boost" in the title ... nothing I saw seems to pertain to what I have going on

I'm about to tie a chain and a lead ball to my foot and jump in the deep end of my pool, this is killing me!

DaleClark

iTrader: (55)

Do you have those giant injectors tuned in at all? You're firehosing fuel into the car.

Do you know what kind of shape your exhaust is in?

Dale

Rpeck

The S-AFC is tuned... I'm getting no crazy smoke or anything .. I'm sure it not a fuel issue... I mean it runs through the RPM band after the secondaries kick in just fine (it runs JUST like my N/A) ... the car runs perfect! just no freakin possitive boost at all. Is there any electronics that could cause this? I tested the wastegate with my air compressor set at about 12 PSI .. it retracted perfectly .. and then recalled back in the closed position. I just got back from spending another $50 at the auto parst store fitting radiator hose to my intercooler... I replced all the intercooler hosing and got all new clamps, I am sure I don't have a intake leak around the IC. The exsaust is old but the CAT is new ... and like I said I passed a california smog check 2 with this car yesterday .. so I know the exsaust has to be in decent shape... and even if it was fugged up I sould get at least a # or 2 of boost.

I just got back from another test run .. and I have a full 3 inch cone TID intake, and the A-AFC only shows 22% air intake a full throttle in 4th gear at about 5.5k RPM that seems low... ??

I'm so bitter right now, I'm thinking of calling my insurance company tommorow, change to full coverage and push this damn thing in a lake.

Rpeck

BTW: the injectors worked perfectly with the 10 ohm 10 watt radio shack resistors.. .

RestoTII

have you tried possibly taking the filter off and running it, or taking the whole TID off and looking for some restrictions? Sounds kind of like what I'm trying to track down. I'm only boosting 5psi, but occasionally it'll hit around 10psi. Kind of odd, so Ithink it's just a restriction that's moving, and when it's out of the way, it sucks more air in. I could be WAY off with this, but that's what I'm going to try to look for anyways.

Scott 89t2

haha my 89 AFM sees 66-70%...

if the wastegate line was off, it would over boost, not underboost.

it would either have to be a huge leak between the turbo and engine. or the wastegate is stuck wide open. but you said you can see it move? or the new turbo is screwed... does it spin easy with the TID off?


I'd try putting the exhuast on if it's there and see what happens.

Rpeck

Well her eis a Pic of my intake setup .. its full 3 inch .. I really don't think ther eis any restrictions. I wish I had your problem 5 PSI is alot better than 0

Rpeck

Yas I am having the 3 IN full RB exsaust installe don tuesday .. I am having a shop do that, I'm not sure what might need wleding .. and I'm not a welder. I pulled the wastegate line and got the exact same thing .. I did see that wastegate bar move a good inch and a half or so when I used my air compressor to test it. I have chaged ALL the hoses fromt he turbo to the intake, and tightened every clamp with a ratchet. And ya the turbo spins perfect, nice and smooth .. and it feels really balenced, no play at all.

Scott 89t2

when they have your stock precat off, get them to spin the turbo from the other side as well. and make sure when that side is spining. it moves the front side....

Rpeck

Can that get loose, or break? or somthing .. cause I know it did spin from both sides before it was on the car.

Rpeck

If your telling my my turbo may be bad, I will **** purple bricks! Not to mention how unhappy I will be .. I spent ~$900 on it.

Cheers!

RPeck,

do you not sleep? how can you finish doing so many mods to your car in one day.

Rpeck

Haha, i work like a freak on Friday nite, Saturday, and Sundays.. I have to work Mon-Fri, I sleep about 5 Hrs a nite on weekends I catch up on weekdays about 6 Hrs a nite. But I won't sleep well tonight I'm bitter.

Not to mention my GF is ready to KILL me. This car has got her so pissed, but fug it .. if she can't accept my true love then she does'nt deserve my love.

But she is usally cool when she knows I'm really bitter about somthing - like this.

Rpeck

Okay, I am having some thoughts about this. ...

1. is there anything electrical that can cause you to not boost? I always thought it is basically all manual. The car originally had a twin scroll setup .. that has been disabled, I have tried running the car with the 'green' twin scroll plug installed and not installed, no change... but maybe I need to fool the ECU? I would think not, but I am tossing everything out at this point.

2. Can you visablly see the wastegate with the turbo mounted on the car? I made sure the rod moved, but I could not visably see the puck in its relation to the wastegate hole.

3. Is there any way to test for boost while at idle? I would like to see whats going on under the hood. I.E.. the BOV ETC., and test for some kind of a leak .. maybe my IC itself has a crack or somthing .. but I cant check these things while driving.

4. Can I eliminate my IC all together.. If I conect piping from my turbo to the intake .. strait though .. what will be the ramafacations of running the car without a IC .. just to eliminate this a a problem for sure.

5. Can the fuel ratio affect boost that much? If my S-AFC is way off, (I get no odd smoke or anything like that) will it cause me to get no boost?

6. What is the best way to decide if I got a DOA turbo? Is there any tell tale signs of a bad turbo? It spins fine from the front, and feels very balanced, kind of like spining a tire... it will continue to spin if the brearings are good... it feels like that, hard to explain.

7. Is there any 'mission critical' vacuum lines? Is there any lines that will cause total lack of boost? I have replaced ALL the vacuum lines on the car, and I have the pill in the boost sensor line. But I will tripple heck if there is particular lines that could be in question.

8. Fill in the blank ... this is all I can think of at the moment... but I am open for ANY ideas.


Thx Again,

Robert

hypntyz7

Anytime you get a bunch of mods done at one time and you hae problems you try to go back to bone stock and see what happens. I always make it a solid rule to get a baseline with stock parts first, so that i know everything is right, then I move on to mods, one by one. That way diagnosis is easy.

DO you have a FMIC by any chance? I once had a friend who put a big *** FMIC on his FC with stock turbo and exhaust and it dropped his boost form 6 to 1 with no vacuum leaks detectible anywhere.

Other than that, a turbo is purely mechanical. The only things that can affect it are airflow impedances before or after it, internal failures, or lubrication failures. IF the wastegate were stuck open, you can have slow spoolup and low overall boost but you should still see 4 or 5 if not more with your mods unless you ported the **** out of it

BEst thing to do is put back in the stock injectors(I tried 680's once and lost a lot of power at stock boost levels) set the afc correction to 0% across the board and see what you get in a closer to stock condition.

Rpeck

Well I had the same condition when it was FULLY stock (yesterday) .. I just did not hit the gas far enough to kick in the secondaries. but I had ~0~ boost up to about 3.7k RPM's. I tried to hit some boost just to see... and it never did. I assumed it was the upraged turbo with the stock stuff. Infact I made a post about it. All the sugestions were, "wait till you mod it" so i did, and I have the same thing.

Infact the smog tech comented on it, he asked "is your Turbo working?" I asked ... why? he said "cause I'm not sure if it will pass like this, I am having to give it alot of gas to get it to the dyno speeds" I told him, hold it steady around 3k .. keep your eye on my AF guage and make sure you test it in closed loop mode. It was a no pass no pay place .. he wanted his money as bad as I wanted the certificate. Lemme look for my other post about this ... before I changed anything. I will edit when I find it.

Rpeck

Okay this is it... My orignal post...

maybe it has helpfull info.

https://www.rx7club.com/forum/showth...hreadid=120353

Infact this is a great post to tell you all where I am comming from

hypntyz7

Well, you were given(IMO anyway) a bit of bad advice to mod your car first. IF you cant get stock boost levels out of a stock car(with upgraded turbo and chip of all things) there is a problem that needs to be dealt with long befor eyou ever try to do other stuff. Sure, theyre sort of right in the fact that the mods should give you more boost, but you shouldnt have to do all kinds of mods to try and reach stock boost levels.

You say you saw the wastegate rod move under test, which is good. Are you sure it is still connected to the actuator arm(rear of turbo)? Mine used to come off all the time, because the stupid little snapring clip fell off due to rust. I finally had to weld on a nut to hold the rod in place. Even with the wastegate stuck wide open(if the rod was off) you shoudl see some boost under WOT, it'd just take 3-4 seconds to build.

You asked if there is a way to "test" the turbo in the driveway, well, no. You can grab the throttle, open it for a second, then let it snap closed, which should build a bit of boost and make you blow off a fair amount of air. If you play around like htis you might find a hose off or something, such as the one on the back of the stock IC which is easy to miss. Still, you'd have a vacuum leak if this were the case.

It's pretty puzzling, really. Unless you have a big airflow restriction somewhere, the thing should be working like crazy. You didnt say what kind of upgrades were done on the turbo, if it is modified enough it can be slow to spool on low end, but you should still see something. Also, if you have any normal running problems such as lack of/irregular spark or fuel delivery it can cause lack of boost, but you say it runs smooth and perfect. Al;so note that even though you're about halfway through breakin, the new engine still isnt sealing really great yet adn thus has some compression blowby, power loss, and not quite full airflow yet, but you should still see 3-4psi minimum.

Go back and check all your turbo intake hoses, the BOV for being set too soft(it might be leaking out your boost if defective or set wrong, as some of them can be adjusted to blow off sooner or later), the IC could have a leak in it, or the exhaust could have a clog somewhere. Take the exhaust OFF and make a quick run. You should see 10psi minimum like this. IF you get no change, rule out exhaust restriction.
Just go at it one thing at a time, process of elimination. At this point it's gonna be hard for someone on this board to come up and say "hey this is what the problem is" without being in front of your car and putting their hands on it.

Rpeck

Okay, I have had enough Vodka to sink a small ship tonight.. my dissapointment is imeasureable. Hopefully somt posotive news in the morning ..

Thx,
Robert

Rpeck

Thanks Kevin for your thourogh response. I am not sure the actuator is on the WG puck, I asked above if I can see that without pulling it. But ya at WOT I get nothing even for extended periods of time.

If I hit the gas .. in neutral, or by cable under the hood. I get nothing as far as boost guage responce.. nothing at all. and my BOV is a Turbo XS type H, in other words its a 10-25 PSI spring in that BOV .. so i know its not going off early, plus no boost with the stock BOV ...

I have the hose on the back of the IC installed and hooked up tight I tripple checked that stuff. I have a screw type hose clamp and new hose on it.

My airflow should be sick! look at my intake, full 3 inch, no restrictions...

the only thing I can do is the "exsaust" thing you mentioned... but if I pull it and drive around here I libale to end up in jail ... and like I said .. cats not even clogged or I would not have passed smog yesterday... and even if it was stuffed with a log of **** and clogged.. I should get 'some' boost right?

Rpeck

I am at the point, I really do think I got a DOA turbo. Now... I'm not sure yet .. but everything I see so far, and everything I have tried is starting to point to that... or the Waste gate, and I did not do the wastegate either.

I have done everything on this car myself except 2 things ... the Turbo, and the Exauhst.

hypntyz7

You'd be damn surprised what a clogged exhaust can do for you. I have roughly doubled hp output on cars that had busted exhausts. Leaks, bent pipes, clogged or disentigrated cats, etc. can screw you quick. Prolly not the problem, but pull it off and make a midnight run anyway. ONe WOT run and the boost needle should peg, if not, it's not your problem.

As for the turbo, theyre really simple devices. 2 fans, one driven by exhaust flow, and a bearing in the center that requires oilflow. Give it airflow and oilflow and it just about has to work unless that bearing is fubar'd which would be unusual fom a reputable shop using new parts. Keep i mind stock turbo bearings can last 150k or more if cared for, so a new bearing isnt gonna be bad in my mind. But yeah, process of elimination, put the stock one back on :-0