hey there. ive got a 1985 gsl-se with 158,000kms on it.

just recently i have been having some really weird idle problems.

whenever i start the car it will rev up the usual amount, then as it slows down to what should be the normal idle speed it will drop much too low (about 500 rpms or so) then if you give it a bit of gas it will shoot up to about 1500 or 2000rpms and rev like that until the car heats up. THEN after that when the engine is running at operating temp. the rpm will flucuate horribly. it will start at 750 or so rpms, and then drop to 500, then surge back up to 750 after a short time. i have been racking my brain, and the brains of everyone else i know but i CANNOT figure this out. i have been thinking fuel pump problems. but i cant be sure.

can anyone out there help me!?!? if you need more specifics or anything just ask and i can tell you. THANKS

 

Take off the BAC, clean and test. If that doesn't do it, start looking for vacuum leaks and check the tps.

 

most likely its the tps...i had the exact same problem except the revs ranged from 1000to 2500 until warmup....readjusted the tps and no more problems...that is till the rebuild, now i can get her to start

 

most likely its the tps...i had the exact same problem except the revs ranged from 1000to 2500 until warmup....readjusted the tps and no more problems...that is till the rebuild, now i cant get her to start

 

alright. for the first reply, i dont have a/c so i dont think that is going to be my problem, but ill give the TPS a go. thanks guys. any other opinions PLEASE feel free to answer.

 

BAC valve is the Bypass Air Control valve and it does affect the symptoms you listed.

 

i dont know if this is a symptom of the problem either, but ive been getting shitty as hell gas mileage aswell. so far ive driven 230kms and im at about a third of a tank. and during acceleration in first gear at about 3500rpm there is a little surge of energy it sorta feels like. i have a feeling it could be my fuel pump starting to go or something. anyone agree?

 

https://www.rx7club.com/1st-generation-specific-1979-1985-18/1st-gen-rx-7-faq-page-237777/

Scroll down about 1/3 of the page, there are a number of links to SE idle and surging problems.

 

holy cow! thats a alot of information. wow i bet that will solve my problem. haha daaaamn

 

Welcome to the forum.

 

thanks. hopefully i wont be around too much asking for help!

 

You might be suprised, it can be addictive. Informative too.

 

mines having the same problem, i know for sure its the TPS (tested it), replace.