If any body knows about this problem or/and has experienced it, knowledge is much appreciated.

My 93 rx7 run great, no problems starting, no leakes, nothing. the only problem are the turbos. Some times they work some times they don't. When they do work (usually after the car has really warmed up) they read about 10-12 psi through out the rpm range. But sometimes there will be no boost at all. I can hear the turbos spooling but there is no (turbo) acceleration or boost reading on the boost gauge. And some times the gause will read 0 boost and at around 4000 to 6000 rpm the boost comes out of nowhere and hits hard and normal. My mechanic was suggesting something about a specific valve to the turbo units. Does any one else have any suggestions. Turbos are two years old remanufactured and have about 20000 miles on them

 

I would check the turbo control solinoids. I had the same problem. If they heat up, cool down they might not make proper contact due to expansion and contraction. It wouldn't be the turbos as they are new. I would look in to the solinoids first. They are hard to trouble shoot as you check them when the car is cool and then when it warms up then it doesn't work. Just replace both of them and save yourself the troubles down the road. Or just convert to nonsequential. Hope this helps.

R.K.

 

The obvious thing to check is to be sure your wastegate is not getting stuck open. It could be caused by a bad actuator or (more likely) in the exhaust manifold itself.

 

Sounds like either the charge relief valve is stuck or an actuator isn't opening. If the charge relief valve gets stuck open, you can spool all you want and get no boost. Or if the actuator to the wastegate flap is not working consistently, causing the wastegate to get stuck open; again no boost. I doubt that a heat-soaked solenoid is the root cause; more like a busted solenoid ... but you never know, this is an RX-7. The previous post is right though ... you ought to replace them, if you haven't already. Good luck.

 

Question about that last... The charge relief stuck open would eliminate secondary boost and primary boost over 4500 rpm, right? The charge control would also have to stick open to bleed primary boost under 4500 rpm, right? Just trying to educate ME on sequential ops.

 

Yeah, that's correct. I also forgot about the charge relief chamber ... it may not be called that ... if it cracks, you can also leak boost from there as well.