stock 93 rx7 33,000 miles when u get on the throttle the car goes to 10 psi but then at 4500 rpms the car drops to about 7 and then slowly drops passes 5 never going back to 10 psi. i am not real sure what to do i have only had the car a month. any suggestions???

 

This is usually caused by a vacuum line coming off of the "Charge Control
Solenoid". The lines sometimes pop off while under boost. The solenoid
in question is located under the upper intake plenum. Look in your
shop manual on page F-10, the solenoid is item F. If a vacuum line has
come off here, trim off the end of the line where it has become loose,
and re-attach it to the solenoid. It is helpful to use wire-ties or
a dab of sealant to keep them from coming off again in the future.
Motorcycle shops also sell small, wire clamps

 

i get that same boost patern in first gear and dont know why. but, all my other gears have perfect secondary. hope you find that leaky boost.

 

i went through and tightened all the hoses to the air charge valve and all the other hoses i could see on the passenger side. can something go wrong inside the charge control solenoid itself?? are there anymore hoses goin to the secondary turbo that might be coming loose? again i dont wanna dig to deep in the engine yet, i dont know enough about it. thnx

 

Has the car had this boost pattern since you got it?

I have the same problem that I'm tracking down. Basically I have a 13-5-5 pattern. I was fixing some things and when I put the upper intake manifold, throttle body, etc, back on I got this pattern.

I know it's something I did, just trying to figure out what is the hard part. I've got everything back off today and I'm looking into it. I'll post back if I get it fixed and hopefully the solution will work for you.

 

everybody please check the main cat, and if you still have it check the pre cat out. if they are bad it will cause low boost on the second turbo. i had a bad cat and my boost was 12-6-6 if you dont already have a dp get one. greatly extends the life of the turbos and keeps much heat out of the engine bay. if you already have one check the main cat as it may be clogged.

 

That's not my problem. I have a high-flo cat (only a year old) and my boost pattern was fine until *I* worked on the car.

 

yea it may not be yours then but check it anyway. i got a high flo cat and it was only 6 months old and went out, you know more about your car then i do though, good luck

 

i havent been into the engine any and as far as i know the first owner hasnt either. i am going by a buddies exhaust place tomorrow to c if he can get a downpipe. any suggestions??? for temporary what do u think about gutting the pre-cat if u can?

 

did this problem just start?
are there pills in the wastegate lines? [usually they will affect the *entire* boost pattern.

it could be the soleniod in question though. or, it could be as simple as the coupler hose that is off of the Y pipe and joins the splitter. i have seen this boost pattern on 3 fd's and all 3 had a fokked up IC or routed piping coupler......

shameless plug for RIKKI........

JUST GO NONSEQ. IT WILL ALLEVIATE HEADACHES.

it wirked for me....i like it....

 

also, as i forgot to add, and not too insult, bu tyou should redo the vacuum hoses as well. it is a must. And unless you or the other owner has had it done, it is most likely not done. the low mileage on that car screams stock hoses. and being original and from 93, it most likely rotted out and ready to break. you really won't notice until it begins to crumble when you replace it.

also check the check valves.....

 

i would recomend getting a real downpipe. any rx7 shop can get one and they all are about the same. i wouldnt recomend gutting the precat. it is worth the weight savings to put on a dp and gutting is actually kinda hard. but definaltly get rid of the precat, they are nothing but trouble. have the exhaust place check the main cat out also, but get the precat first, since that is what i am betting on is bad, and the dp has all the benifits, you will not use your radio for a week i swear, you will jsut listen to the turbos spool, coolest sound on earth.

 

If you have a boost gauge, tee into the lines going to the CCA and CRA. It is important to know if they are getting the proper signal. If you don't have a boost gauge, then get a cheap auto parts store gauge.