Looking for anyone that understands and can help me troubleshoot my boost issue. I basically did the hose job and custom intake and since then I am only getting 5 lbs max boost on primary and no transition to the secondary turbo. I did replace solenoids while doing the hose job, I don't have the equipment or the know how to test the solenoids, the ones I replaced were turbo precontrol/ wastegate solenoid, charge control, charge relief solenoids all due to broken nipples. I suspected the intercooler pipes so I replaced them with the hard ones. I have the stock y-pipe and coupler. I thought it was a kinked hose under the upper intake manifold, I checked and found a pinched one, fixed it and still same issue. I am getting only 5 lbs max and sometimes my vacuum is 21 when cruising and letting off the throttle, otherwise it is 15 on the vac side. I had normal boost before I did the job, I just need to know where the problem could be coming from, I am chasing a problem somewhere, anyone think they know what is up? what sounds like the main cause of this problem, is this a normal sounding boost issue? I am stuck.

 

check your double throttle.. might be stickin

 

Check if you switched the connectors on the PC and WG solenoids.
Just switch them and see if it fixes it.

 

I did and no difference at all. Anyone that has anymore ideas please hit me with them. I wish I could understand exactly how everything works, I have diagrams and hose charts and it is hard as ****. I know it worked before I replaced those solenoids and I took extra care to make sure all the hoses were intact, I even used sprngs in the tight bends so no kinking would occur. I wish I could test the solenoids. I am about to order new solenoids and a new y-pipe(efini) and see what happens. so what do you guys think I have provided as much info as I can mention.

 

what would cause only five lbs boost max with no transition, is it due to the turbo control side? I need a little more insight on this, I know some of you guys are real good at explaining it, I have learned everything I know on here. thanx

 

...you only need an ohmmeter and a couple of lead wires to test the solenoids see f-191 in service manual....also go to juckyard and look in any 90ish Mazda for solenoids...they are all the exactly same.

 

...oh i forgot...re-check and double check that you have the hoses correct...make sure the one-way check valves are working and in the right direction and finally remember there are the restrictor pills at the boost control and pre-control actuators...you probably tossed these with your old lines...

 

Start by confirming that the restrictor pills are still present.

 

Take a good look at your check valves, and both the pressure/vacuum chambers. If you do not see any visible problems, then pressure test them using a mityvac or something similar. If you find no problems, test the Turbo Control Actuator solenoids (there are two of them)

-Rob

 

For you to be only getting 5psi <7psi on the primary turbo air flow must be venting somewhere (so this probably has nothing to do with the pills and or wastegate/precontrol solenoids). It sounds like youre losing primary boost maybe through the charge control portal being open, allowing flow out the charge relief valve. Maybe start by making sure the lines to the charge control actuator are getting the right signals.

 

Start here ---> http://www.autosportracetech.com/RX-...leshooting.htm

 

good stuff so far, I definately have the pills in there, I made sure of that when I did it the first time. I pulled each one off and replaced them one by one and made sure the ristrictors were straight, good thinking though. Ledfoot thanx for the tips. Aristo I think you might be on to something, maybe you can elaborate on what you were suggesting about the charge relief valve.

 

First off, if you tossed the wastegate lines with the pills you would only get 7psi of boost and the secondary would come on line. You are getting 5 psi which leads me to think that either your blow off valve might be leaking some pressure or one of your check valves are in the wrong way. Also I would triple check your hose job as it also sounds like you put the wrong hose on the wrong nipple causing the solinoids not to work properly.

R.K

 

Sonix, it looks like everyone agrees that your problem is likely on the intake side of things, possibly a leak somewhere. If you didnt connect the lines to the charge control actuator/solenoid/vacuum tank properly, the butterfly valve might be open during primary operation allowing flow to leak through the CRV. As a first step, if you dont have an obvious leak I would try either t-ing a boost gauge to the input on the charge control actuator and verifying it is getting the right signals, or just wiring the thing shut and seeing if you get more than 5 psi below 4500 rpms.

 

thanx guys this is what I have been waiting to hear. I will do evrything I can to check the CRV and check these other ideas. I agree, everything I have read leads me to believe it is either intake or turbo precontrol. Aristo is there specifically a place I can find a detailed write-up on testing the charge control actuator. I don't have an obvious leak so I am digging through the haystack. Anyone got more info on how to troubleshoot the system other than what has already been mentioned. the more the better.

 

by the way are the BOV and CRV interchangeable? I am wondering if not if they got switched when doing the intake. just a thought.

 

I agree with Aristo - if it were just a wastegate/precontrol issue, you'd still get up to ~7PSI.

I think the "CCV + CRV staying open" explanation makes sense; regardless of the CCV, if it were working correctly, the CRV would be open only until 4500RPM, after which it would close. So even if CCV isn't working correctly, you should be able to get past 5PSI by redline, if nothing else is wrong with the system. If CRV didn't close, then the explanation makes perfect sense. So it's likely that CCV is never getting vacuum, but then CRV must never be getting vacuum either.

I'd guess a vacuum leak upstream from both CRV and CCV solenoids (supply side). That's where I'd start looking...

 

very interesting info DigDug, anymore elaboration, cause I can't get more than 5 lbs no mattre what I do. what is the best way to check the CCV and CRV and make sure this is not the prob?

 

I will take as much "theory" from anyone who wants to give it, anyone with similiar problem and fixed it?

 

To test, t into the CCA input with a boost gauge and floor the car. Below 4500 rpms I think you should see the vacuum in the vacuum tank, and after 4500 rpms you should see about what your secondary boost level is. On the CRV, the input should see vacuum below 4500 rpms and the secondary boost level after 4500 rpms.

 

First off, you have to be 100% sure that you have NO leaks in any of the pressurized hoses. Check all of the 1" hosesm, the ABV (aka BOV) hose is known to harden and leak. Also, take off your coupler on your y-pipe to ensure that there are no leaks. Basically, check all of your pipes OUTSIDE of the car. Flex them a little to look for cracks or holes. This will eliminate most of the problems that can occur.

Having a MityVAC is VERY helpful. You can use it to test your check valves, ABV, CRV, solenoids, and actuators. You can use it to test your ABV and CRV per the FSM. Check your pressure chamber and vaccum chamber for leaks. Check that all of your check valves are not stuck or blown. After that, go on to the two the three actuators (turbo control, turbo pre-control, and wastegate). Make sure that the rods are on all of the corresponding gates. Also check the CCA to make sure it's not stuck open.

If all of that checks out, it's time to test each actuator with a hand pump per the specs. listed in the FSM. This is where a handpump really comes into play. If all the actuators turn out fine, then you really have something else that is wrong and will be a lot harder to troubleshoot (routing of your hoses/solenoid rack). Start with what I told you to check over before you pull off your UIM and test each solenoid.

Good luck with your quest for working sequentials. Once you reach the state of working sequentials, not only will you have learned all of the functions of the sequential system, but you will have also had a turbo system that is really, really fantastic.

Incase no one linked you: http://www.autosportracetech.com/RX-7/rx7stuff.htm (helped me out a lot)

I know it seems like a bit much to troubleshoot it all, but it's a lot better of a method than trying to find a solution, then "testing" each one after you "fix" something. If you need further help, feel free to message me on AIM. I'll be more than willing to help, if I am not busy with something.

 

Much thanx, this is comprehensive info, I will start by checking out a mighty vac and read on how to properly test everything and just do it and go from there. I am sure I will run into some problems, so if anyone has advice as the best way to go about doing this (easiest method) suggestion is welcome. WaLien I might be contacting you soon. thanx again.

 

Get a Mityvac Silverline Plus kit, not just any old Mityvac. It will test both pressure and vacuum at the flick of a switch. You can use it to tee into a line under the hood, then run that line into the car and take it for test drives to observe if each line in the system is feeding the proper pressure at the proper time.

Since you said you did a vac hose job, I suggest investigating if the lines are connected correctly. Sometimes the location of a hard line on the diagram looks different on the actual rats nest - you have to trace the line in the diagram and rats next to make sure it's the proper one. Very easy to get them crossed.

Dave

 

nice. anywhere suggested to pick up the M-Vac silverline plus kit? Sears? thanx Dave. I am soaking up this stuff and I will fix it somehow? I am determined to figure this **** out.

 

I agree with the Silverline. I got just the "regular" MityVac and it does not read pressure, only vaccum.