first off i have a 30min ride to work in the morning. so on the way in this morning everything was fine for the first half of the ride boost was were it should be. then about 20min or so into my ride i started noticing that in all gears i was boosting 6psi and no more. My pattern was 6-5-6 in all gears.


Can a clogged down pipe be the culpert, it seems to happen only when the car has be driven for a long time(20-30min). It will not go passed 6psi on the boost gauge.

Please i need some good feed back here.

The car has 86,000 miles on it and 8,500 on the rebuild has the orginal down pipe and mid pipe.

thanks for the help guys.

 

Do you mean pre-cat and cat?

 

yes sorry

 

Check the wastegate actuator. Sounds like the wastegate isn't functioning since you are limited to 6-7 PSI (which is the lowest the wastegate will allow as long as there aren't any other problems).

 

checked that this afternoon that is functioning ok as far as i can tell. This only happens when there is an excessive amount heat build up.

 

i don't think it would be a clogged cat/pre-cat as this would tend to effect the upper rpm area.

it sounds as though boost is being controlled off the wastegate and precontrol actuator spring pressures only. which means the wastegate and turbo pre-control solenoids may not be working. see if you get any error codes in these areas, otherwise check the plugs to the solenoids

 

or because you state it happens with heat, it could be the front turbo inlet collapsing under vacuum

look throught this:
http://www.autosportracetech.com/RX-...leshooting.htm

 

if you punch it does it jump to 10 but immediatly drop back to 6?......im having a similar problem but i belive my main cat is clogged. btw, get rid of that stock pre cat.

 

controll solenoid. if it's fine hot but goes to ~6 psi the solenoid is prob not functional when hot. how did you check it?

 

Remove the solenoid, do the check while it's cold; then put it in the oven and test it again after it heats up.

 

/\ i agree that is a good way i was wondering how he checked it

 

Sounds like the TC solenoid.

Remove the UIM. Under it is what the manual called a T/C (turbo control) solenoid. Due to its location, this sucker stops working when the engine is hot.

Buy a new one. Wrap it in heat shielding.

 

rx7???rx7#1,
Please keep us posted im having the smae problems

-Cody

 

i am going through a similar problem, and poman maybe onto something
https://www.rx7club.com/showthread.p...79#post3212979

the Turbo Control Actuator is run by 2 soleniods; 1 that supplies vacuum and another that applies a pressure to activate the actuator. the pressure and vacuum should only be activated by the solenoids after 4500rpm. you can test it just as i did (where i found the vacuum solenoid not working)

 

this picture may help to find solenoids and hoses

http://www.zeroglabs.com/rx7/images/...oses.color.jpg

 

thanks for the info guys

yesterday when i was lookin around i noticed a vacuum leak in the center of the engine under the uim. i sprayed carb cleaner there and the car stumbled. it also sounds like a hissin noise. the car has the orginal vacuum lines in it. what do u guys think could this the problem.

 

sorry the problem didn't happen today at all. This seems to be very intermitent.