throttle plates
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throttle plates
Well, all tests and checks have been done over the past 5 months on my cousins rx7 to diagnose why secondary turbo/boost wont hold 10psi. Primary holds boost strong at 10psi until about 4,500rpms when it falls to 0. Everything has been checked on the car and even a full hose job has been done. the problem still has not been resolved.
But we might have found the problem...
its something called "throttle plates". can anybody here give me an idea or experience with this part of the car. Anybody had run ins with it? we will not be able to check them until next week.
But we might have found the problem...
its something called "throttle plates". can anybody here give me an idea or experience with this part of the car. Anybody had run ins with it? we will not be able to check them until next week.
Originally Posted by rynberg
It sounds like a charge relief/charge control issue to me.
I agree.
As far as the plates:
Double Throttle Control
* This keeps a second set of Secondary throttle plates in the throttle body closed. If the Double Throttle control is not working properly, (i.e. secondary always closed) then maximum boost will be restricted to ~5 psi.
* This keeps a second set of Secondary throttle plates in the throttle body closed. If the Double Throttle control is not working properly, (i.e. secondary always closed) then maximum boost will be restricted to ~5 psi.
Since you are dropping down to 0 after secondary, that doesn't seem like your problem.
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From: Washington DC
i dont know, we are just lost. we checked everything on the car including the charge relief/charge control issue. still no fix. a friend has the same problem on his r1. he thinks its the throttle plates as well. he is going to check and see if that fixes his.
I Like Beer
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From: Vancouver Island Oceanside
Well, If you've checked everything (Did you check the health of the secondary turbo?) then you might need to try the non-sequential experiment. It shouldn't take too long to discover if you can keep some boost above 5000rpm.
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WWFSMD
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"Throttle plates" is an extremely generic description -- there are 3 plates in the throttle body, 2 DTCS plates, and one charge control plate. It isn't the DTCS (double throttle control system). I don't think you would get 10 psi below 4500 RPM if they were stuck shut. There is another throttle valve (with a plate! 
) in the y-pipe. I think the proper name is the charge control valve. If that mechanism is stuck or if the actuator and/or its control system is dead, you will lose boost after the 4500 RPM transition. The mechanism on mine became sloppy some time ago and would delay the transition in a strange way (not the same as your problem, but things can go wrong with the valve).
During the vacuum hose replacement job, were the hoses just replaced and reconnected as they were before, or were they reconnected according to a known-accurate (since the one on the hood is known to be inaccurate) diagram? If they were connected up wrong, and they were simply replaced with new hoses that are also connected wrong, whatever problem exists would not be fixed. I used a variety of diagrams when doing my vacuum hose job because I was having trouble with boost and figured if there was something wrong that I didn't want to repeat the misconnection with new hoses. The parts diagrams from the parts ordering microfiche are pretty handy, in addition to the more familiar one that has been colorized and worked over by many folks to make it easier to follow.
-Max
) in the y-pipe. I think the proper name is the charge control valve. If that mechanism is stuck or if the actuator and/or its control system is dead, you will lose boost after the 4500 RPM transition. The mechanism on mine became sloppy some time ago and would delay the transition in a strange way (not the same as your problem, but things can go wrong with the valve).During the vacuum hose replacement job, were the hoses just replaced and reconnected as they were before, or were they reconnected according to a known-accurate (since the one on the hood is known to be inaccurate) diagram? If they were connected up wrong, and they were simply replaced with new hoses that are also connected wrong, whatever problem exists would not be fixed. I used a variety of diagrams when doing my vacuum hose job because I was having trouble with boost and figured if there was something wrong that I didn't want to repeat the misconnection with new hoses. The parts diagrams from the parts ordering microfiche are pretty handy, in addition to the more familiar one that has been colorized and worked over by many folks to make it easier to follow.
-Max
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From: Washington DC
Originally Posted by maxcooper
"Throttle plates" is an extremely generic description -- there are 3 plates in the throttle body, 2 DTCS plates, and one charge control plate. It isn't the DTCS (double throttle control system). I don't think you would get 10 psi below 4500 RPM if they were stuck shut. There is another throttle valve (with a plate! ) in the y-pipe. I think the proper name is the charge control valve. If that mechanism is stuck or if the actuator and/or its control system is dead, you will lose boost after the 4500 RPM transition. The mechanism on mine became sloppy some time ago and would delay the transition in a strange way (not the same as your problem, but things can go wrong with the valve).
During the vacuum hose replacement job, were the hoses just replaced and reconnected as they were before, or were they reconnected according to a known-accurate (since the one on the hood is known to be inaccurate) diagram? If they were connected up wrong, and they were simply replaced with new hoses that are also connected wrong, whatever problem exists would not be fixed. I used a variety of diagrams when doing my vacuum hose job because I was having trouble with boost and figured if there was something wrong that I didn't want to repeat the misconnection with new hoses. The parts diagrams from the parts ordering microfiche are pretty handy, in addition to the more familiar one that has been colorized and worked over by many folks to make it easier to follow.
-Max
) in the y-pipe. I think the proper name is the charge control valve. If that mechanism is stuck or if the actuator and/or its control system is dead, you will lose boost after the 4500 RPM transition. The mechanism on mine became sloppy some time ago and would delay the transition in a strange way (not the same as your problem, but things can go wrong with the valve).During the vacuum hose replacement job, were the hoses just replaced and reconnected as they were before, or were they reconnected according to a known-accurate (since the one on the hood is known to be inaccurate) diagram? If they were connected up wrong, and they were simply replaced with new hoses that are also connected wrong, whatever problem exists would not be fixed. I used a variety of diagrams when doing my vacuum hose job because I was having trouble with boost and figured if there was something wrong that I didn't want to repeat the misconnection with new hoses. The parts diagrams from the parts ordering microfiche are pretty handy, in addition to the more familiar one that has been colorized and worked over by many folks to make it easier to follow.
-Max
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