Hi everyone,
I'm new to RX-7's, as I have only owned mine for 4 weeks. 3 days ago my 7 did not want to make any boost from the primary turbo. It was reading 0 on my boost guage, and I could definetly feel it wasn't working. I didn't rev any higher to check for secondary boost in fear of wrecking something else. I should note before this happened, the car flooded while trying to start, and the check engine light came on briefly after driving. The previous owner had all the stock hoses replaced with silicon hoses, new turbos where installed 6 months ago, and a new TPS sensor was installed. I've been reading a lot of posts and have figured the problem should be with some type of solenoid valve, actuator, a blown off hose, or clogged pre-cat. I don't think it should be the pre-cat though, as it has been drilled out. Another problem I've had before this, is around 5000 rpm's (after the secondary kicks in?), the car doesn't want to make anymore power, and will not rev past 6000 rpm. I have read it could be the MAP sensor or any of the previous mentioned parts failure. The idle sometimes runs a bit low when the car is warm, around 500-600 rpm (is this normal?) If anyone knows which of the many solenoids, actuators, etc. that may be defective, I would appreciate any info you could give. Also, is it safe to drive it with no boost? Thanks.

 

First thing, if you saw the "Check Engine" light come on, pull the codes to see what it was:

http://www.scuderiaciriani.com/rx7/engine_codes.html

Next, here's a guide to troubleshooting the turbos:

http://www.autosportracetech.com/RX-...leshooting.htm

As far as driving it with a boost problem, it's not necessarily a good idea. If there is a leak and the turbos are still trying to make 10 PSI of boost (and never making it because the boost pressure reading is down stream of the leak), then you'll be overworking your turbos which is not a great idea.

 

My thoughts: If its not making ANY boost on the primary, it's probably a large gaping hole in an intercooler coupling, or one of the y-pipe couplings. There isn't much that controls the primary turbo, so it's tough for anything to fail. If your primary isn't working however, it's damn near impossible to get the secondary to function properly. I'd say first work on fixing the primary, and see if the seconday fixes itself with it.

About the idle, as long as it's idling your in better shape than most other FD owners

I agree with Mahjik about the driving it with a boost problem. I'd think you can drive it, just don't push it, the turbos don't need to be worked that hard. And keep in mind that if there is a large hole in an IC coupling, the engine will be sucking in unfiltered air through that hole. i.e., get it fixed pronto, and only drive it if you have to.

 

Hi guys,
Thanks for the replies. I've checked every coupler suggested for leaks/cracks but unfortunetly found nothing wrong. I am fearing the worst, that my primary turbo is broken. When I tried revving the engine (in neutral), no air was coming out the y-pipe. There should be right, or do I have to put into gear? Is there any other problem it could be (open wastegate?) because these are new turbos, and not even 3000 miles on them.

 

boost issues are hard to diagnose...

if you are mechanically inclined, go to that link that mahjik sent you and start reading. and search here for various means of dianosing and fixing boost issues.

otherwise, find yourself a good rotary specialist in your area. go to the regional forums here and ask around.

 

Problem fixed! Car runs flawlessly. The c-clip, that holds the turbo control actuator rod to the turbo control valve fell off. That's odd though, I thought that valve was only for the secondary turbo. Guess not, but my 7 works now and I'm happy. Thanks guys for reading/posting. :-)