EDIT ITS A S5 91 coupe..
my first rx7 . suppose to have a rebuilt motor . it runs good start right up but after warming up the idle just starts jumping from 700-almost 100 . the car starts to warm up fine no problems but after its fully warmed up it jumps . i drove the car for 4hrs strait no problems at all just idle . NOW tonite i was revving to show my freind the exhaust system and when i look under the car the CAT WAS GLOWING RED . but it kept doing after that just sitting there , the car was normal temp too..
and last the car feels like it has no power after 6k until 8k at all . it doesnt cut out just no power . let me know wat to look for guys my first 7 its about time lol.

 

You might be running extremely rich, or your cats are starting to clog.

 

hmm...gas is alrright on it dont use too much

 

Our previously NA 90 had a clogged cat last year. They're 20 years old after all. The easy way to test is to simply take the exhaust off and go for a ride (it'll be brutally loud). If the 6-8k lug goes away, tada!

Boucing idles are common though so be sure to read the FAQ and go thru the 2nd Gen archives. Lots of good stuff. Chances are it is that the TPS is out of adjustment and/or that you have a small vacuum leak. You can read how we searched out our vacuum leak right here.

Good luck.

 

kid said he adjusted the tps , its only after the car warms up so im thinking bac vavle

 

any one esle?

 

Having just gone thru a similar process I think you'll find it is best to not guess but instead to go methodically thru the standard tests both in the "bad idle" faqs and then thru the FSM's diagnostics.

If the TPS is really right (and people find they have to test them over and over to get em right) then it is probably a vacuum leak. If you really think it is the BAC then unplug it and see what happens.

 

ok ima try that...if u know a link with all vacumm lines let me know

 

ok i disconencted it, it held idle with out jumping for a while then it started doing it again the bac vavle that is..so ima have to try another one

 

you might have leaking primary injector or stuck partially open, causing over fueling at idle.

 

edit guys i unpullged the tps...wow im a dumbass but yeah i did that the idle went normal then started doing it again...

 

ok i unplugged the bac vavle no diffrence still idles then the idle starts to jump again like some times it will idle perfect then most the times the idle jumps after warm up....dont know wat else to look for