limepro

iTrader: (2)

My car is non sequential, cat back exhaust, stock ecu, stock intercooler, upgraded radiator, pettit intakes, street ported and a few hundred miles on my rebuild and all emissions delete with block off plates.

I have a couple problems, first it is getting very little to no boost and when I let off the gas I get a woo sound. I read on here before about it but it was with sequential and have not been able to find that thread again. I am replacing all my hard pipe gaskets and the y pipe o ring to make sure there is no boost leak there and testing everything else. I am getting around 4psi then it is bleeding off to 0 rather quickly.

If someone could point me in the right direction for what is causing this sound it would be appreciated, I remember reading that people had it when they had boost problems and it helped fix it.

If there is any other information the gurus on here could give it would be greatly appreciated. I am keeping it at low boost, no pills or boost controller at 7 psi even after this is fixed until I can really get in there and upgrade some more but would like to know it is at least running correctly before digging into it further.

If any other information is needed let me know, I hate being vague, I just have no other clue how to explain the sound.

okevin

iTrader: (1)

sounds like that

(before i ripped my stocks out)

limepro

iTrader: (2)

Yes that woo sound, someone else got it right by saying it sounds like ric flair under the hood, still no fix though.

okevin

iTrader: (1)

yeah im not sure, back then i wasn't able to find an answer but i posted that video on here maybe someone can point you in the right direction now that they have something to work from

limepro

iTrader: (2)

I need to pull the all the piping because I still have the stock intercooler pipes and I know they crack. Might just switch them to hard pipes.

Happy Meal

iTrader: (21)

Ric Flair WOOOOOOO! - YouTube

turbojeff

iTrader: (30)

No need to just go replacing stuff. Sounds like a boost leak, the first hose to look at is the one coming off the y pipe, then the rest until you find it. Make sure the Bov is hooked up right. I think you eliminated the CRV right? Did you cap all the holes tight?

Stock ECU, stock cats? Will have lots of lag with that setup but you should get full boost up in the rpm range.

SA3R

I think the WOOOOO is because its excited to be an RX-7.

Seriously though, it sounds like a boost leak to me. I had a similar noise when my Y pipe coupler popped off a while back. I hope its just a boost leak.

limepro

iTrader: (2)

Full open exhaust with stock ecu, hence why no pills running off wastegate. The turbo and everything were off recently and the reason why i am replacing the o-ring and gaskets it needs it. Once i get it boosting correctly i can upgrade other stuff.but i don't want to just mask the problem with new parts.

limepro

iTrader: (2)

replaced all gaskets and o rings and still loosing boost and that annoying woo sound. I used the rotary resurrection website to check everything but I must be missing something. I even finished deleting all of the unused solenoids as per their website. I must be missing a cap off somewhere, going to take the uim off again and recheck everything but I ran out of light for the day.

I need to try and find the thread on the woo sound but with the solenoids gone it can't be one of them.

limepro

iTrader: (2)

I just realized I may not have capped off the open nipple on the wastegate actuator, would this cause the sound and low boost?

DaleClark

iTrader: (55)

How is your blowoff valve hooked up? Are you using the stock one?

When you get that sound after letting off the throttle it could be compressor surge.

Dale

limepro

iTrader: (2)

hks, large hose from the large hole on the y-pipe and small hose from passenger side front nipple.

codywelshrx7

iTrader: (14)

I had a similar problem ended up being the check valves i would check those out.

limepro

iTrader: (2)

There is only 2 and one is the viton from dale clark the other is for the map sensor that I did not change, could that check valve even cause that?

Enthalpy

iTrader: (10)

^ wrong. You should only have 1 check valve if you kept the purge control system. NO check valves if you deleted it.

The "check valve" to the MAP sensor actually has a filter, replacing this with a check valve that does not have a filter is a bad idea. Not accusing you of it, just making sure people who read this know that.

I think cody was too lazy to read the OP, and assumed you were still sequential. Either that or he's willfully ignorant of what "non-sequential" and "emissions delete" means.

In these technical/troubleshooting threads, it would REALLY help if people could read the whole damn thing and understand the terms used before posting useless CRAP. That way, a helpful thread is not muddled up. /rant


In any case, here are my thoughts:

If you didn't cap off the nipple on the wastegate actuator, the pressure signal from the turbos would leak out through the opening - the wastegate would "see" a lower pressure than is actually being produced. So, it would not open as easily - you would be spiking. Could cause some weird sounds and boost issues (happened to me before, slight tear in a vacuum cap). EDIT: The vacuum cap was actually on one of the nipples connected to the primary compressor housing. Caused slow response and lower boost than expected for me.

You mentioned a couple things:
- Stock ecu
- Full NS
- Full emissions delete
- Stock IC and IC hoses

Assuming that you did the non-sequential conversion correctly, my money is on a boost leak (as stated before) or the stock ECU not being happy about something being missing. Very likely both.

Running non-sequential twins with a full exhaust on the stock ecu is like giving the rotary gods two middle fingers. I'd stay below 4k RPM until you can introduce some exhaust restriction, port your wastegate, or buy a standalone ECU. Preferably the last 2.

limepro

iTrader: (2)

Yes the stock filter is on the map sensor, all emissions are deleted, I correctly deleted all solenoids with 330ohm 1/2 volt resistors and have no check engine lights.

I didn't cap off the wastegate actuator and was still not getting boost spikes, in 1st gear I get no boost at all, in 2nd+ I get right around 5psi and it will slowly bleed off to 0. I took off all of the IC piping and pressure tested them and they held. The woo sound seems to be coming from the drivers side so I have more to go through tomorrow.

I have tomorrow off so will pulling the uim off again and making sure all of the connections are good and everything is tight and in the correct places. Flaco from on here is the one who did my rebuild, I am sure he did it correct and hate to second guess him I just can not figure this out.

Guess it is time to buy that pfc, wastegate was ported and I am trying to keep the boost at 7psi but first I need to get there.

Enthalpy

iTrader: (10)

I think you need to pressure test the system as a whole, instead of all parts individually.

I still think you have a boost leak. Charge control actuator may also not be removed from the Y-pipe (or may not be wired open). Could also be that the Turbo Control gate was not wired/welded open.

If the car idles fine and the RPMS come down without the car almost dying, then you do not have a problem after the throttle plates. The only things that should be connected to the UIM would be the MAP sensor, line for FPR (stock or aftermarket), PCV, boost gauge, ISC, and BOV. You've already said the BOV was routed correctly, so there is nothing on the UIM that would be causing your problem.

A working NS set-up will not be able to maintain 7psi. It will creep to 11psi minimum after about 4k RPM, if your wastegate was well ported.

limepro

iTrader: (2)

Thank you for the info, i will check everything tomorrow and check back. I plan on upgrading ecu in the next couple weeks, as i drive the car maybe one a week i should be ok til then.

NoPis10

iTrader: (29)

I would stay OFF the boost until you break the motor in....You said it only has a few hundred miles and the proper way to break it in is to stay off boost.... I know it's hard but have patience so the motor will last....

I have 700 miles on my motor right now and I will NOT boost it till it sees at least 1500 miles.... Thats the way I have always broken in my motors and it's worked for me so far....

I would also have the guy who did the rebuild fix the issue....You paid him for a rebuild so everything should be 100% once you get it back....if not then his job is NOT complete.

Enthalpy

iTrader: (10)

Forgot to mention Air temp sensor Still irrelevant, but felt necessary to add for completeness.

Regarding your ECU choice, if you will be self tuning then the PFC is a great starting point with a lot of support on the forum. You'll need the commander and the datalogit to go with it. But there are many better options out there like AEM, Haltech, Link, etc. which have higher logging rates, closed loop boost control, multi-dimensional fuel correction tables, all for not much more money. Do a lot of research before making a choice. I learned a lot about tuning with my PFC, but now, I wish I had something more fully featured just so I can get a smoother tune.

If you will be getting it tuned, just get what your tuner prefers.

limepro

iTrader: (2)

Fixed it, I did boost twice, no more until break in is finished, gonna go on a nice long highway drive today. I went through everything under the uim, every hose, connection and cap off and nothing was wrong. I put it up on ramps and crawled under and saw that my turbo actuator was closed instead of open. Switched that and completely changed the exhaust sound.

I had to boost twice because the first time one of the intercooler connections blew off when it hit 7 psi, fixed that and 2nd time it hit 8psi and stayed there.

Now I feel better about doing more upgrades...unless my wife makes me sell it now that it is "working".

Enthalpy

iTrader: (10)

Glad to hear you fixed it. Told you the problem wouldn't be with the UIM. :P