OneBadRx7

Hey guys I need your help here, this might get kinda long, sorry. Not too long ago I started having boost problems, I was only hitting 5psi on the primary, a slight dip to 4.5 on the transition then back to 5psi so I decided I was going to take off my UIM to examine a possible blown off hose. Well when I got the TB off I looked around and decided I didnt feel comfortable taking the UIM off so I put everything back together. I did however disable the double throttle by removing the hose and pluging it up, but I did not cap up the nipple on the double throttle actuator yet. I also do have the "home depot" style boost controller and I thought that might be a possible problem area so I removed the needle valve and connected the hose straight through(no pill mind you) and still had the same boost of 5psi. Can anyone help me?? If you need more info please ask because I would like to get this solved by the time I go to Chicago next weekend so PLEASE HELP ME!! I am sure this has happened to plenty of you out there so someone has some ideas, I REALLY appreciate any help and tips anyone can provide, thanks,

OneBadRx7

Oh and at idle I am getting a vacuum of 20, in case anyone needed this info as well, thanks!!

7-sins

Sounds like the TCA isn't opening fast enough, maybe bad TCA?

mjw

iTrader: (1)

I would check all your intercooler hoses very closely. I had a boost problem two weeks ago, I would peak at 7psi on both turbos.. turned out to be a tear in one of the couplers. I was still getting a vacuum of 19 and it idled fine, the leak only opened up when I was on boost.. I could hear it.

Matt
93 SSM

al900rr

Do you hear weird noises when you let off at 5psi. I had the same problems when my turbo actuator solenoid went bad. I think if it was the couplers he would get weird boosts patterns and not a consistent 5lbs. Listen for leaks and where they come from. Could also be a problem with your secondary. Take off the intake on the secondary turbo from the bottom of the car and see if the secondary spins at all.

poss

iTrader: (5)

since you are not getting boost on either turbo and you are running a fairly consistent boost, i would suspect a boost leak, and not the control system. check all of the intake hoses between the turbos and the throttle body. do you still have the stock crossover/y-pipe? that is a prime candidate as well as the intercooler hoses. good luck

Rated R1

If you re supposed to have a restrictor pill in the hose you will never make more than 7 pounds of boost. If you do not get at least ~8-9 lbs of boost the secondary turbo will not come online. So check on that. Also check the check valve that runs to the pressure chamber. Derek Vanditmars has an excellent site to check out if these do not help your problems.

http://home.iSTAR.ca/~dvandit/turbocharger.htm

Yenven

Is the pill one way or does it matter what way u put it in?
IF it does what is the right way.

OneBadRx7

Whats the TCA, so far you all have given me alot of options to look into and I really appreciate it guys, anyone else want to throw in their 2 cents??

Thanks,

spyfish007

Don't forget to check for a bad BOV .....

7-sins

That is also a good point, I had the Air Bypass Valve go bad on me. The TCA is Turbo Control Actuator, it basicly controls how much exhaust flow the 2nd turbo gets. The pain with this acutator is it has two sides (vacuum/pressure) to make it open fast enough. I am thinking maybe one side is bad or the control system for that side is hurting.

OneBadRx7

Alright guys here is an update. I went to A-Spec Tuning's grand opening, they looked at my boost problems, said they supposedly ruled out any bad check valves or solenoids. They pulled the manifold off and they were going to do a full hose job but then they said they noticed that the Charge Control Actuator was bad, said the valve wasnt opening and moving as freely as it should. I am getting transition and I can feel the secondary come online so I know the secondary is ok. I got another CCA and was going to install that but I wanted to see if you guys agreed that this could be my problem?? If this isnt up I am about to just give up, they said they heard no leaks and the couplers all looked good but I am having a second opinion next week, we will see what happens. Anyone have any input on this, I WOULD REALLY appreciate what ever you got, thanks,

Steve

OneBadRx7

oh and what would the symptoms be of a bad BOV?? what would cause it to go bad?

PaulyDee

Well if the Charge control Valve is bad then you have a big drop in secondary boost. The charge control allows secondary boost to come on line. If it fails then it will prevent the primary or secondary to work right. So it is possible thatit could be causing the problem.

As for the BOV, the best way to verify is to detatch the airbox side of the hose, and drive, and see if you here it venting under boost, you should just hear a woosh, when you let off the throttle.



Paul

OneBadRx7

I do have my BOV vented into the atmosphere, I can still hear the woosh but its not as loud as it used to be. Probably because I am not boosting as high though huh. Well I hope it is my CCA. Unless its my TCA, which does what exactly??

Tom93R1

iTrader: (2)

You said that you removed the home depot boost controller and reconnected the hose straight through with no restrictor pill? That could easily be your problem unless your car had the restrictor built into the nipple instead of the pill in the hose. With the hose free flowing you get lower boost. The more you restrict that hose the more your boost goes up. Put the pill in or the needle valve back in and crank it most of the way down (start about 1 turn out from completely closed).

OneBadRx7

I already did exactly what you said, just opened it up one turn and I get the same exact results, only 5psi.

Steve

OneBadRx7

^PLEASE HELP, ANY OTHER ADVICE or is everything pretty well covered??^

OneBadRx7

OK OK, now what the heck is the PCV valve??? Please tell me so I can see if it rattles!!! Thanks,

Steve

OneBadRx7

Oh and I dont know if the home depot gizmo is working but I do know it worked for like a week or so, so I kinda ruled that out of the problem by now.

Rotary93

Steve,

Try closing the HD valve and taking boost up slowly....See if it goes over 5 psi with the valve closed...

But be careful not to take it over your desired amount...just let off...if you go to high you can pop your motor...

Sounds like you have a boost leak somewhere.....Hit me up on AOL IM

stevenoz

iTrader: (27)

First of all forget about your TCA. This is not your problem. Since you are getting 5 lbs on primary...transition....then 5 on secondary you can rule out the TCA. Two things that happen when this is bad is either is doesnt open ( no exhaust flow to secondary turbo which means it won't spin ) or the diaphram is bad which means it will leak down ( meaning you will get normal boost with the primary..secondary comes on and then boost slowly drops because the gate closes off the exhaust flow ).

Have you checked your couplings??? This is the most obvious and you havent said whether you have or not. You can't just look at them... take them off and bend them back and forth to check for splits. Like they said above the first one to check is where the two turbos unite.

Get a vacuum/pressure pump and disconnect the vacuum line to the Air Bypass Valve and also the Charge Relief Valve. Make sure you can't blow through these until you start applying vacuum. Also disconnect the line going to the Charge Control Valve and apply vacuum to it and see it the actuator rod moves and stays until you let off the vacuum. The rod should be out when the car is not running and when you start it it should suck in.

One more easy thing you can do is eliminate the wastegate. Pull off one end of the short hose that comes out of the primary turbo that attaches to the wastegate. Do a second gear run starting at low revs and see if you build boost...just be ready to let off.

technonovice

According to the chart Turbo Control doesn't start until 4500 rpms.

technonovice

http://www.rx-7tt.freeservers.com/rx7stuff.htm

New and Improved site.

OneBadRx7

Well another update, had the new charge control actuator put on and well same thing as before only 5psi so I guess its back to the ol' drawing board. I still have a few of your guys suggestions to try but I need to know what you are talking about, like whats the PCV valve and HD valve?? I still need to check a couple of the couplers on the y-pipe but all the others are ok. Guess I will have the boost control solenoid rechecked and other actuators and such,

Steve