Throttle Positioning Sensor
 

Hey guys, I recently have started having an idle problem to a certain degree, once the car gets somewhat she starts to struggle. What I mean by this is that at a stop sign/light she struggles from 300 rpm to a thousand, like the needle is on a trampoline its really annoying and my friend phillip martin who has an fd suggested that the only thing he can think of is the Throttle Positioning Sensor, anyone care to elaborate or if hes dead wrong which I doubt say it and back it up, also how much is this to get fixed or tuned. by the way its a 86' n/a (duh)
all the best
Stu

That does not sound like the TPS.... Sounds more like a vaccume leak or the MAF....

MAF? im a lil down on my acronyms been in Wein Osterrich for the past 6 months car terms went out the window while studying german

Mass Air Flow Sensor.

Could be a few things really. As for the Bypass Air Control Valve (BAC Valve), have you check It's operation? I'm assuming not. IMO, I'd familiarize myself with a a free download of the Factory Sevice Manual found at www.fc3s.org . You could also look Into a Haynes Manual.

*edit* Look here for a detailed description on the Bac Valve. scathcart explains It's purpose and function better than I do.:p: https://www.rx7club.com/showthread.p...ighlight=valve

thanks well done with the clear and concsise answer, I just got back from the mazda mechanic who I know and respect and he basically gave me the same shpeal, I have an apt at 8:15 thursday for it, so we shall see.
All the best
Stu