7THSIGN

Im getting sick and tired of this car. No boost past 4500 said over and over again. Professionals could not diagnose this car and replaced nearly everything possible in order to hear no boost was still prevalent. The motor itself is in awsome condition, also is interior and exterior. My last step is installing a different set of the stock rx7 turbos that are in good condition. However checkin my stock turbos my secondary is not siezed up on the co-side so I dont see how this may fix the problem. Is my installing of new turbos have any chance of fixing my boost problem. The other thing i think it might be is the tca (turbo control actuator) but i hear its rare for them to go out around 71,000 miles. I just really need advice on if there is any chance i may feel boost at 4500 after installing them. I dont see how the turbos or wastegate that comes with it itself can cause that problem. Someone please help me this issue is depressing me and my money..

DCrosby

I had a bad / difficult to diagnose, turbo problem. I had troubble boosting consistantly past 4500, changed over to Non-Seq. to illiminate boost controll issues... to no avail... problem presisted.... it boosted 8 psi almost everywhere, but once it got past 4500, and it would get 10 Psi, sometimes, and then nosedive, then pickup, spike 11-12 psi, and then nosedive again....

Bottom Line, the Airpump, was going bad @ 55k+mi and was leaking C02 back into the intake tract and causing the mixture to get all deluted of Oxygen + Co2, and once the boost resumed normal pressure, the leak stopped and the mixture went back to normal, built boost, and got messed up again due to the rise in pressure, try this, buy some 3/4" Radiator hose Plugs, and try blocking the airpump, to see if that helps.

Just a warning, blocking the airpump, or messing with the operation is not legal, and can possibly clog your cat, if left like that....

-DC

scotty305

iTrader: (2)

I don't know the answer to your problem, but I felt compelled to respond and let you know that I don't know the answer. Good luck.

-s-

cabaynes

iTrader: (4)

not trying to be rude but there are soooooooo many threads on this same problem.

i just typed in "no boost past 4500" in the search here in the 3rd gen section and i got 67 threads... here are a few of their links:

https://www.rx7club.com/showthread.p...oost+past+4500
https://www.rx7club.com/showthread.p...oost+past+4500
https://www.rx7club.com/showthread.p...oost+past+4500
https://www.rx7club.com/showthread.p...oost+past+4500

cabaynes

iTrader: (4)

btw - it is NOT rare for the TCA (or any of the FD's electronics) to go out at 71,000 miles or even earlier. The amount of heat that builds up in that engine bay is enough to fry them after years of abuse. Don't rule out the TCA or solenoids or anything just because you think it's "rare" for them to go out.

vellj001

Here in Malta we take out the turbos and reservice them with very good results. Once they come back from they look brand new in form and results. It is usually done every time a rotary needs a rebuild.

They are taken to a local engineer who tests them first, If neccessary they are opened apart, all need parts are first manufactured at an enginerring section. Fianlly they are reassembled and put back brand new in our cars.

kuroi FD

just go manual boost controller and get another one for pre spool controller there like 3 bucks at homedepot

1LuckyGuy

i have the same problem it seems that when im boosting the cracks in my vacuum line will leak and the hose will cave in. i just ordered the vacuum hose upgrade kit from rx7 store, to see if that solves it. oh by the way the hose keeps mysecond turbo from spooling

jeremyb

Who were the "professionals"? Were they roatry specialists? MANY "professionals" for general auto misss things on a rotary twin turbo system.

As what stokedxiv said, using a search would work. ALSO making your topic name a LITTLE more specifc than "everyone please respond". Don't think of me as flaming you, just helping you out for future reference so you don't get this again.

As for your problem, there is a link in the FAQ sticky at the top of this sectin. Look for the twin turbo troubleshooting link(forgot what letter it's under). It will help you diagnose every damn soleniod and actuator relaiting to the twin turbo system. Also in http://www.scuderiaciriani.com/rx7/boost_problems.html , there is a HUUUUUUUUUUUUUGE article on steve wyeen fixing his "no boost after transition" problem about halfway down, then after him there is another guy(forgot his name =/), he also has a major write up about no sec. boost.

Jeremy

weaklink

I didn't read past the first line, but I'm responding as instructed. I have had ZERO boost problems since going single. Worth the money for that alone.

dgeesaman

iTrader: (7)

Steve Wynveen and Wael el-Dasher have the articles to read. Print them out, and maybe have a mechanically-enabled friend help to go through them.

Send your address to my email geesaman@newsguy.com and I'll send a spare TCA to you. If it works, you can keep it and send $40. It worked fine when I removed it to try another (I have a slightly too-low transition dip) that ended up not changing anything. I also have a spare mityvac set (upgraded to the metal one) that I'll sell for $35.

Forget what the professionals did - it's not hard to run through the procedures they have outlined. I did them in a few hours with minimal digging into the engine bay.

We have no idea if these shops have used an organized approach to troubleshooting this. Or if they knew what to look for. All you need is a mityvac or pressure/vaccuum gauge. (P/v gauge is like $30 including a tee fitting and rubber hose). Simply: if there is pressure and vacuum going into the TCA at the right time, the solenoids are working and there are no leaks.

I don't go to Fairfax often, but my brother lives down there. One of these days I need to visit him - I'd be glad to help. If you're ever coming near Harrisburg, we could work with it for a couple hours also - I have all the tools. Hell, for all the time/money it seems you've spent, you would be justified to drive up here just so we can work with it for an afternoon.

dgeesaman

iTrader: (7)

I sincerely doubt that replacing the turbos themselves would fix anything. It's the control system that will cause these problems. However, digging that deep into that side of the engine will make it much easier to find and test some of the lines in that area.

Dave

Klar

No boost in sec at all? Primary kicks 10 psi right, then dumps at the transition to 5? If so, swap your precontol and wastegate contol electical plugs. Happened to me when I did the vac job.

If it dumps all boost over 4500rpm then most likely your charge relief system is staying open.

Hope this helps.

AntiVenom7

Just go single.

DaleClark

iTrader: (55)

I'd do some more reading. Seems like pretty much every week someone has no boost on the secondary turbo - it's been well covered. The precontrol/wastegate control connectors getting swapped is a VERY common problem.

BTW, "just go single" is not an answer. There are many of us who LIKE the stock twins. The various problems are SO well documented that most any problem isn't tricky to fix.

Dale

dgeesaman

iTrader: (7)

I agree. "Just go single" kinda pisses me off. Some of us like the stock twins, some of us don't want to buy a PFC, injector, fuel pump and lines, manifold, turbo, intake piping, intercooler, and bov. That's not in everyone's upgrade path. Not to mention, eliminating the emissions that many states require.

Sure, an FD isn't a cheap car, but it's stupid to dump several thousand into a car with a failed $50 part. It's worth trying to find, IMO.

You said the pros installed new parts in places. Which ones?

Regarding the CRV, wouldn't venting it to atmosphere (disconnecting it from the airbox) be a good test? IIRC, the CRV only vents during prespool, so it should stop whistling at 4500.

Dave

Nghtstlkr7

try looking at your cat... i had a similar problem and it turned out that the cat was clogged.
try looking at the simple things first before jumping to the complex (and possibly expensive) systems.

adam c

iTrader: (2)

I'm not going to respond either.

7THSIGN

Thank you guys for all the replys it surely has brung my confidence back up in keeping the car. On going single I dont have the money and I know people with stock turbos that are running "fast" and fine. Here is what I have replaced, check valves, remove intake plenum and replace broken vaccum lines and valve, silicon hose, 3 way valve, rubber 90 elblow, hose, air, pcv one way, spark plugs, earthing cord, water sensor, wator sensor, and 10+ hours of work and computer diagnostics. Thank You guys again I will probably look to installing a actuator that someone is willing to send me I am also thinking the crv is a possible problem. The shop is Performance Buyers Club in manasses run by a owner named Pete who used to work for Autoauthority now bought by Porsche Pitstop.