boost problem
 

on a turbo ii 87
I hear the turbo works, blow off valve is ok and waste gate is ok
but when i get into the revs the car is not generating any power from the turbo ( only a little bit can be felt )

only once it did boost properly from 5000 to 6000rpm

there is no intake and exhaust

how many miles are on the turbo?

Mine did the same thing. The engine was reving hard but it was building little boost. I did the TB mod and and removed the plates and then had serious boost issues. the plates were not opening up all the way.

what is a TB????

TB is either tuburculosis, Turbo Boy, or....throttle body. If its the throttle body then remove the intercooler. Look towards the front of the throttle body and at the front of the throttle body you'll see a rod with a spring over it and a small approx 5.5mm nut on the end. The nut will be facing you. Carefully remove the nut...then the spring, then the rod. Then get a ziptie and put it thru the hole where the rod was and tie it to the throttle body support frame (any part that does not move). That should hold your seconday outboard throttle plates to full open all the time Now go for a drive (don't forget to put the intercooler back on) and see if the boost is better.

Make sense??? Does to me anyway.

you can really wire your secondary plates open with no other adverse effects to the motor?

We are talking about the secondary double throttle.

It's job was to keep nimnulls from going wide open on a cold engine, and to slowly open after warmup.

The first secondary works directly, the double can stick shut.

you mean the plates that are supposed to be removed while doing the TB mod?

**you mean the plates that are supposed to be removed while doing the TB mod?**

Yes. What I described is not the throttle body mod.....what it WILL DO, is keep the number TWO secondary throttle valve full open all the time. The number ONE will still be closed and controlled by your foot.

The number two throttle valve is purposly made to open slower than the number one secondary throttle valve. The is done with a black colored cam and a damper. After a number of years these parts can become worn....as in worn out. That causes the number two to hang up and sometimes not even open. When that happens you don't get the full throttle opening desired and you starve your engine of air. That's what the above post by MONKEYONE suggested.

I suggested this method because.......it does not cost a dime. It takes maybe twenty to thirty minutes to do and you know in forty minutes whether or not that was your problem. If you do the throttle body mod...... well...see you in a couple of days when you might have finished it.....and then that might not have been the problem to begin with and you would have wasted time for nought.

YOu NEED to down load the fsm from the internet for free.

i have an actual FSM sitting here in front of me it came with my car...i was making sure i was totally clear before i went and did this on my precious car and i know what that wiring theses open isnt the "TB mod"...jeez icemark. ive already done the tb mod on a spare TB i have but i just wanted to see if your idea would help my car before i tried swapping the modded TB over to it. thanks man!

This jpg shows the linkage that I mentioned. It takes about fifteen to twenty minutes to remove and tie off. No throttle body removal required, only the intercooler.

If you remove this piece and tie off the linkage to full open it should give someone an idea if the throttle body mod is for them or not instead of doing the mod and then finding out it......was not worth the time.....and buggered up throttle body that no one in their right mind would pay full dollar for if they are buying your car.https://www.rx7club.com/forum/attach...postid=2749392

thanks guys this helped a lot

one more question
even when I open the throttle by hand and i see the secondary open as well shortly after, u say it could still be sticking internally?

It's supposed to open a touch later due to the black cam riding on the dashpot (damper). It's possible that its hanging up sometimes. Removal of the above spring/linkage and tying it full open should resolve any doubt whether or not its that set of throttle plates that is causing your problem.

If you tie it open and the problem does not go away....then press on to some other thing as the cause and consider this having been eliminated as the cause.

If it isn't that....then maybe the precat is clogged??? Or the main cat??? Or???????

i gutted both my cats the other day ...it was no fun. it does sound better and seems to stay a TAD cooler but not much at all.

oo ok but there is no exhaust on the car at all,

but I have checked the turbo, wastegate, and twin scroll, it is all working acording to specs,

but I do have some (little) bad idle as well, however there is no vacuum leaks that could be found nor is there an air leak

sure you arent hitting fuel cut with no exhaust ?

I WANT TO THANK ALL THE GUYS THAT RESPONDED TO THIS POST.
IT HELPED MY A LOT AND THE CAR IS RUNNING LIKE NEW AGAIN. IT WAS THE SECONDARY ON THE THROTTLE BODY.

ONCE AGAIN THANKS ALOT.

AND ONE MORE QUESTION IS THERE SUCH A THING AS RX7 MEETS ONCE A YEAR OR SO WHERE EVERYONE MEETS UP

i just removed my secondary linkage...much easier than a TB mod and it helped out alot...thanks HAILERS

I have the same problem on my rebuild...
I think i'll try this little trick to see if it helps at all

yeah you should try it man...i didnt have any big problems, but doing this trick seemed to help the responsiveness of my car and might have even add a HP or 2

all this time I was having boost problems no one mentioned this to me. I am going to try this later. Thanks.

hey hondahater where in louisiana are you from...i was born in Slidell!

lol, I know where slidell is I'm in lake charles! Nice to meet a fellow louisianan! :)

yeah its always a pleasure...good luck with your car, it seems that i can maybe build boost a LITTLE quicker it might just be in my head and it seems to run smoother after taking off that linkage. It was very simple to take off even though i did lose the spring that was on the linkage:)

lol, sounds like something I would do :) Anyways my car is at a friends right now putting on another turbo because I couldn't build boost with the old one however he said that the one that came off was bigger and better :( Anyways if it still doesn't boost with this other turbo I know it will be the secondary plates because that is the only thing I haven't done yet.

What is the DOWN side to removing/tying off those plates?

Hey I wired that open and had ahuge differance!

hey hate to open a dead thread but I was wondering where exactly is this linkage you have to take out? Can you see it from outside the thottle body or do you have to go inside it? THanks! Any pics would be great!

anyone?

hu? Are you making fun of me ??? don't get it... Anyways I would really love if someone could give me some details on this, thanks.

I put it on your other thread. What I'd do, since it's so easy to do, is not do it right now. Put the other turbo on and see how it does first. That might give you a clue about your old turbo. Then if that new one has the same boost problem, go remove the rod with the spring around it. It's just two small cotter keys that have to be removed along with removing the intercooler first. And one piece of safety wire or zip tie.

This way you won't be guessing about the old turbos condition.

It takes but thirty to forty minutes to remove that rod with intercooler and reinstall it and go for a ride verses taking the throttle body off and removing the throttle plates etc. That sounds like a all day job for the first time.

hey man again thanks for helpin' me out I apprectiate it very much!!! Only problem is that I don't see that rod at all... Strange I wonder if one of the previous owners took it out? Well if you go back to the link you provided I put a picture of my tb, THanks again!

Hey you know were to find me if you want to copy my throttle body mod! Its one of the first things I did to my car! So I really couldn't tell you what it feels like without it!:D

hey whats up man! haven't heard from you in a while how was your 4th? Well I finally got everything back together and took it for a test drive and at least now I got boost but not all that much and now I got a oil leak :( but anyways I should have it up and running soon. Anyways one weekend I would love to come by and take a look at the mod to see if maybe I'm just missing where this rod is going to the secondary throttle plates.

Not a problem! Im at school most of the day so just drop in!;)

MORE http://www.teamfc3s.org/forum/showth...785#post340785

Thanks for the diagram! If you where here I would buy you a beer :) Anyways I just looked and that linkage is gone! not there! guess the tb mod has been done? There is a pic at fc3s http://www.teamfc3s.org/forum/showt...0785#post340785