TrboSpdAnt

iTrader: (5)

OP: Just out of curiosity, what mods are you running? I'm interested in looking at your map, just for comparison purpose.

RX7_FD3S_JDM

mods are exhaust inc decat (no manifold/down pipe), intake, intercooler and power FC.

Ive also just converted it to the "poor mans" non sequential.

But as Im locked out I cant choose the non sequential setting on the commander.

How do i unlock it so that I can choose that setting?

The reason I ask is because im not getting any boost since doing the poor man non-seq conversion and I believe it has something to do with the wastegate actuator which IIRC is controlled by the ECU when both turbo's are charged? see quote below.

When both Turbochargers are in operation, the Wastegate is actively controlled by the ECU to allow exhaust to be bypassed around both of the Turbochargers to allow control of boost pressure.

arghx

iTrader: (3)

I do not trust the stock ECU on an engine with a catless exhaust. This is because the stock ECU mapping is configured for more exhaust restriction (poorer flow) and it may not have the proper fueling and spark to be safe. The wastegate mapping is also not configured for such a free flowing exhaust. Catless exhausts can also overwhelm the wastegate and cause dangerous overboost regardless of what boost control method you are using. You really need to port the wastegate to be safe, or introduce more restriction to the exhaust.

Somebody locked the Commander from adjustment. Since you have a JDM car I presume, it could have been tuned at an Apex'i authorized shop in Japan and they locked it. An FC-Datalogit box will allow you to disable the lock through a laptop interface. You really should have one of these boxes anyway, as it is the only viable way to load and save maps.

The wastegate solenoid bleeds air from the pneumatic wastegate actuator so that boost may rise from the spring-regulated pressure of about 7psi. If your boost pressure is below 7psi you have something else going on that is not directly related to the wastegate solenoid. It's hard to say what that is right now. There is a trick to controlling boost with the Power FC on non sequential and single turbo setups. It requires a Datalogit to access the settings required. That's a side issue though: you could convert to a cheap manual boost controller, but that is not going make you go from 0 boost back to stock levels.

I suggest you purchase a Datalogit. But based on what you have said so far, turning off "sequential turbo control" isn't going to solve your problem. It sounds like you have more fundamental issue like a split hose or cracked exhaust manifold. Search through the 3rd generation section about all the basics of troubleshooting boost leaks on the stock twins.

RX7_FD3S_JDM

Thanks for the speedy reply . Just some more info about the car so you can build a better image of whats going on..

The reason I decided to go non-sequential was because I wasn't getting secondary boost. Primary was working perfectly fine, but when it came to 3500-4500 it would just go flat as a pancake

So now I've gone non-seq (thinking it would ~kinda~ solve the problem) and I have NO boost, I beleive that it's the exact same problem as before.

My prediction is that the wastegate actuator is bust and the flap is either stuck open/shut.

Do you think that could cause the above symptoms/problems?



Thanks again.

arghx

iTrader: (3)

If the wastegate were stuck shut, you would have uncontrolled spiking. If it were stuck open completely, it is possible that it would build very little boost.

RX7_FD3S_JDM

So if it were stuck open, primary boost would work fine? I guess I need to check the actuator? I know I need to check the rod's movement etc but I can't see it for the life of me.

Please could you take a picture of where abouts in the engine bay i should be looking. I have the CAD images but its not the same.

thanks

arghx

iTrader: (3)

The wastegate diverts exhaust away from the primary turbo's exhaust side. If it were stuck open, you would have a lot of trouble building boost whether you are sequential or non sequential--but there are other things that can cause low boost.

You have to take some stuff off to get to it, and you might need to access it from below.

RX7_FD3S_JDM

Spot on

My wastegate is well and truely seized!

arghx

iTrader: (3)

How do you know it's siezed?

RX7_FD3S_JDM

I've taken a few bits off to try to move the rod/arm back&fourth but its not moving.

Any ideas?

arghx

iTrader: (3)

it's hard to say without the car in front of me. The wastegate is spring loaded shut and will only open if you supply a steady 7+ psi into the actuator.

Banzai-Racing

iTrader: (11)

Supply pressurized air and see if it moves, the typical failure would be closed causing overboosting, I do not see any chance for the actuator to fail in the open position.

RX7_FD3S_JDM

Just out of interest, is it safe to run these two open?



Just wondering if they NEED to go onto the intake pipe or if they can get air from anywhere?

Thanks

RX7_FD3S_JDM

So this is the engine. as said above, I did the pikey (poor mans) non sequential mod thinking it would solve my boost problem but i still have problems. in fact im getting no boost now. And another thing ive noticed is that i can feel one intake sucking in the air but the other one not nearly as much. It being non sequential, shouldnt they both be pulling the same?

ItsFun

iTrader: (25)

Have you verified that your turbo actuator is functioning. My bolt came loose once and i had a no boost problem. The actuator is on the manifold right by the engine. Check it out, slap some grease on the rod and go for a test drive, if the grease doesnt move then its not working
This is best accessed from under the car

TrboSpdAnt

iTrader: (5)

Idyllically, they would pull the same, given a couple of variables:

TID length and diameter have a bit to do with it, but you may need to verify that the 'flapper-door' is either open, all the way, removed, or welded properly.

Additionally, check to make sure that the bolt that was mentioned, above, is in place and secure.

Try adjusting the setting(s) to your WG. Duty-cycle may be way too low, resulting in boostlessness.

RX7_FD3S_JDM

All fixed and working as non sequential

Thanks to everyone who took the time to reply to this thread



All i need to do now is to try and get full boost @ 3500 rpm instead of 4200(ish) rpm

ItsFun

iTrader: (25)

What was the problem