ok, i have a 1989 GXL NA, it has 219369 miles on the stock engine. Strange issue. When i run the car initially it WILL NOT go over 6300 RPM. I will drive it to base and then.....if i shut the car off for 2-4 minutes and run it again, it will run perfectly fine all the way to red line. then after about a few minutes of running again it will intermittently go to red line and then gets back to the 6300 RPM wall.

I have rewired the injectors and tested them and all work.
(thats what i was told to do since they were corroded)
ALL main electrical and grounds have been re-done and cleaned.
the fuel pressure regulator was replaced about 15k miles ago

when it gets to the 6300-6500 RPM it sputters insanely (at full throttle) and will not move past it, if i half throttle it, it will go to red line. im thinking it could possibly be my air pump or (maybe) my pressure sensor???
i was thinking the ports might be stopped up with carbon but if that was true.....why would it be able to run well after ran, then shut off for a few minutes?

any other ideas on what could be the cause? i know there are more but im just drawing a blank.

 

Have you checked for codes?

https://www.rx7club.com/2nd-generati...ouble-1005343/

 

It sometimes will throw the engine light on when running but by the time i get to a stop it goes out. Ill try to see if i can pull a code tomorrow when my snitch neighbor isnt home

and thanks for the link, after reading that im sure one of my injectors went out.

 

vacuum leak could be causing the VDI to malfunction or your engine just may in fact have a 200K rotary killing miles on it.

 

I found that one of my vacuum hoses is oversized at my EGR valve......would that also impact my port actuators?

 

EGR? do s5 n/a california cars even have egr?

Even with the 6pi and vdi not functioning the car will get all the way up to redline, its just terribly slow. I am guessing vacuum leak, cat, or bad sensor(maf, h20, iat).

 

It sounds really stupid but I had the same experience on my 2nd RX7. Guess what? It was low on oil.....

 

Wow that's over 350,000 KMS on a 13B NA!
Impressed! Sorry I dont have any advice to offer though.
When do the extra ports normally open? How is this functionality tested?

 

My guess would be vacuum leak, but could be anything from TPS, air flow meter, O2 sensor, injectors, fuel filter, fuel pump, cat.

 

forgot to add oil metering pump.