speeddemon7

Basically ive had this problem for a little while now.What weird is that if I gun it the car is slow to start moving.Very little torque untill I get too about 4000rpms where things feel a bit better. It almost feels like the primary turbo is spooling but it isnt making any power and then the second turbo kicks in and I feel the car pull better. Heres the part that I dont get.
If the secondary turbo needs 8 psi too kick in then why am I feeling a transition and then more power ? Because I havent seen past 7 psi in quite a while. So technically My second turbo shouldnt be kicking in.This much I know.
Does anyone have a clue as to what causes this kind of problem?
So far im suspicious of the following,

Main cat- could be clogged
I know the pressure chamber check valve is bad
Perhaps a air leak coming from the acv,
Bad primary turbo? not sure how likely this is

Hopefully someone can give me a good clue as to what this could be.
Thanx

speeddemon7

mmmmm bump

iluvmy3rdgen

Have you checked and re-checked all you intercooler pipes and couplers?

dgeesaman

iTrader: (7)

There are a couple of mistakes that can lead to 7s on the boost. I can't remember if it's switched connectors on the precontrol and wastegate solenoids, or the missing restrictor pills. Hose leak is still possible also, but you said you checked that.I guess a clogged cat could do it, but usually it won't show on the low end. Also, check the blow off valve (ACV) - if that's bleeding too low you could get the same problem. Come to think of it, make sure your CRV and ACV aren't switched.

You can look it up at the turbo troubleshooting site in the newbie sticky thread.

If you already checked that, I'd take my boost gauge and start teeing into the various places in the control system to see that the solenoids are feeding the actuators the right inputs.

The turbo generally doesn't just go 'bad' and affect boost patterns. Boost patterns are a matter of the exhaust doors and charge valves not controlling the flow properly.

Dave

areXseven

iTrader: (1)

Check for a bad (leaking) BOV or loose bov hose connection.

wrankin

Check your wastegate solenoid and lines first. It sounds like your wastegate is not getting vac to hold it closed and is just flapping open at the spring tension of 7psi.

Do a search, it's a common problem.

Good luck,

-bill

speeddemon7

Doesnt the greddy profec become the wastegate solenoid? and the stock wastegate solenoid is in essence eliminated? if so Perhaps the boost controller is fucked and or one of the lines is screwed.
I also thought that the turbos being bad was fairly unlikely.I still hear them spooling up just fine. Just no power.
The exhaust note has also been slightly louder which tells me that one of the exhaust portals is staying open.
So now im thinking either wastegate,pre control and or turbo control actuators and their controll systems.
But like I stated earlier the boost controller is in charge of wastegate actuation.What are the odds that my boost controller went bad? Has anyone heard anything regarding the greddy profec b spec 2's just dieing all of a sudden?

iluvmy3rdgen

A few people on here complain about the Greddy solenoids going bad. When you installed it did you cap off the line going to the wastegate where the stock solenoid went and put the greddy solenoid in between the turbo and the wastegate? I had a few boost issues before, one was the BOV popping off the y-pipe and the other was bursting one stock IC hose or connector after another.

iluvmy3rdgen

The blow off valve is actually totally differen from the acv. The CRV and BOV could be switched (vacumn hoses controlling them) but the ACV is actually completely operated by three plugs.

speeddemon7

right now im thinking the greddy is at fault.Ill have to tear the car apart once again to get to the bottom of this bullshit.
In any case one things for certain.More money outta my pocket.

WaLieN

Not necessarily, it could be something as simple as a loose hose. If you use the search with my SN and "turbo" you'll see that my problem (erratic boost in one gear, no boost in another) was solved by connecting a hose that went to the hardlines to the TCA (behind the air pump).

It sounds to me that it could be one of two things. Are you actually making a peak of 7psi and are you making the 6psi at 3000rpm? Well, if it's spooling up slowly, then it could be the turbo pre-control actuator or solenoid. But, you should disregard that until later as the pre-control only controls the gate the allows a little exhaust gas to flow into the secondary turbo to pre-spool it. That mainly effects the speed at which the primary spools and the transition/dip.

//side note: a handheld vaccum pump is a nice thing to have, as you can only create so much vaccum/pressure with your lungs.

First off, make sure all of your vaccum hoses are in order. Check with a good vaccum diagram to make sure ALL of your hoses are in order. Something as simple as a loose hose can mess things up. Also, check your other hoses like your 1" hose that comes off of the y-pipe for leaks. A dry/brittle hose will not seal well, and may cause a leak. This step also includes the check valves.

Second, check your wastegate and tc solenoid which are mounted on your UIM. Use the FSM for the procedure (under the intake section).

Third, check the pressure chamber and make sure that you can hold ~10psi for about a minute or two. Then do the same but with ~25in/hg on the vaccum chamber (behind your ps pump). Without proper vaccum/pressure, your actuators will not function correctly.

Fourth, check the abv (aka -- bov) and the crv with the specifications found on the FSM. These can be leaking off too early, causing low boost.

Fifth, check to see if all your actuators are functioning correctly. Use a hand operated vaccum to ensure they they are operating at the desired vaccum/pressure. Again, the FSM has the numbers they need to meet.

If all of that doesn't check out, you will have to start looking under the UIM for other problems. Testing the solenoids on the solenoid rack under the UIM can be pretty rough and time consuming. Sometimes, the solenoids don't operate correctly at higher temperatures, but work just fine at room temperature. A good way to check for this is to bake them a little before you test them. Another problem is that they may not be able to work at higher pressures (+12PSI), but you shouldn't worry about this.

I'm pretty tired right now (just got back from JGTC/D1 weekend), so I'm sorry if any of this is confusing. If you have any further questions, feel free to IM me on AIM. I know it can be frustrating when such a complex system is not working. You may feel as if you will never find the solution to your problem. You may also feel like the Mazda engineers are a bunch of idiots. You may also feel as if non-sequential is the way to go. But you know what? You will find your solution. Mazda engineers were not complete idiots (the sequential system is a very amazing/precise system once you learn more about it). And non-sequential is not the way to go (once you feel how quick the sequentials can spool up with the right tuning, you'll never want to go non-seq). Just stick with it and you'll find your solution.


I believe in you, and so does Tony Robbins.

dgeesaman

iTrader: (7)

Sorry about that, I meant ABV (Air Bypass Valve) which = BOV. The ACV is just part of the secondary air system which has little to do with boost control.

So it oughtta read:
----------
There are a couple of mistakes that can lead to 7s on the boost. I can't remember if it's switched connectors on the precontrol and wastegate solenoids, or the missing restrictor pills. Hose leak is still possible also, but you said you checked that.I guess a clogged cat could do it, but usually it won't show on the low end. Also, check the blow off valve (ABV) - if that's bleeding too low you could get the same problem. Come to think of it, make sure your CRV and ABV aren't switched.

You can look it up at the turbo troubleshooting site in the newbie sticky thread.

If you already checked that, I'd take my boost gauge and start teeing into the various places in the control system to see that the solenoids are feeding the actuators the right inputs.

The turbo generally doesn't just go 'bad' and affect boost patterns. Boost patterns are a matter of the exhaust doors and charge valves not controlling the flow properly.

Dave
---------

dgeesaman

iTrader: (7)

The only vacuum pump you should consider is the mityvac silverline series. It does both pressure and vacuum with minimal fuss and has sufficient range to do all the required tests for this car. Buy it online for as little as $60.

Dave

iluvmy3rdgen

I totally agree, http://www.costplustools.com/store/s...oduct_id=46537

speeddemon7

I have a mitivac that does pressure and vacuum.So this inst an issue.
You said to make sure that the pressure chamber and vacuum chambers hold pressure and vacuum.I already checked for this.Theyre both fine.Heres what I did find though.
The pressure check valve is leaking.So I would think that vacuum is leaking back into the pressure tank. Or something like that. I think im going to replace the check valve and see what changes if anything at all.
One things for certain.I had the car run correctly for two days and I loved it.Thats the only reason why Im on this long quest to have a fully sequential setup that works.Because when it does work its awesome.

dgeesaman

iTrader: (7)

Yep, it's probably a good idea to replace both of the green/black ones.

Dave

WaLieN

I agree. Call up Ray Crowe at Malloy Mazda and have him ship you the 3 check valves. Chances are, your's are probably either leaking or really lazy by now.

speeddemon7

what do you mean by really lazy?

WaLieN

It might be sort of lazy in the fact that it takes a lot of motivation (pressure or vaccum) for it to open up. Basically, the break pressure (pressure at which the valve opens) has increased with age, thus being more "lazy".

You did mention that the check valve was leaking anyways, so you might as well replace it. A lot of people go with alternative check valves. Unless you can get them for free, don't bother. The Mazda ones lasted this long, so you know they are worth their sort-of-steep price tag.

djseven

iTrader: (56)

May not help much but I sold a profec B Spec II to RotaryRessurection. It worked fine for a couple weeks and then just died. The Boost Controller was only a couple months old. Just my input.

speeddemon7

I suppose theyre alright.Although I have seen heavy duty ones for about 10 bucks.I forgot who posted pics of them.I guess ill have to see what Ray is gonna charge me for some check valves and we can go from there.

WaLieN

The thing about the metal ones are that they are rather large, which would cause them to be rather difficult to fit in.

speeddemon7

yeah. thats whats making me lean towards the mazda oem ones.but if the metal ones were smaller i would gio for the heavy duty ones.less to worry about.

iluvmy3rdgen

Yeah some did post the brass check valves from www.mcmastercar.com and they are bullet proof, but huge. Mazda oem ones will be sufficient for another so many thousands of miles. Call Ray at Malloy.

kevinvr6

iTrader: (1)

turbo diagnostic page

http://www.autosportracetech.com/RX-7/rx7stuff.htm