91 rx7 450-750 inconsistent pulse + flickering lights
 

Hey I have a 91 rx7 that I am just trying to go through. I have already checked and searched but I need things narrows down. The car runs good I am just narrowing down problems. First off I have adjusted the tps and made new grounds (engine+frame & battery+frame). As far as the idle...if I try to adjust the air idle screw it will not raise. I can only lower the idle and the more I turn it out I can hear the pod filter getting louder sucking in air. (Because of the plate being so open?) So I adjusted it to where it doesn't make a difference so it is not open all the way. The car doesn't idle consistently though, when it is very hot and the clutch fan is at full load (I think) when I roll up to a light the idle will drop below 500 and then search for 750. When I hold the brake down it doesn't help. At this point it just searches between 500-750. I heard vaccum leaks cause a high inconsistent idle but mine is very low and doesn't do it all the time like when it isn't that hot out. As far as the flickering lights go...I replaced the battery and checked the alternator and it is putting out 74 amps. If you need any more info and things I have done please ask! Thanks!

welcome to the board. :)

it's probably a vacuum leak. for what it's worth, vacuum leaks can cause high, low or no idle depending on where the leak is and how big it is.

The BAC helps keep the idle at 750 rpm especially under load although there can be a lag between the idle dropping below 750 and it returning back to 750.

The initial set coupler should be jumpered when adjusting the idle and the idle should only be set when the engine is fully warmed and not partially.

Make sure the Green/Red TPS wire is set very close to 1 volt w/key to on after the car has been driven for 20 minutes or so.

Thanks for the responses guys, I did check for vac leaks and couldn't really find any. When I sprayed a little into the filter it stalled too. One observation that I made is that with the o2 sensor unplugged it doesn't make the slightest difference. If anything it is a little smoother with it unplugged. The wire going to the sensor is hacked up so I wanted to see if it would make a difference. Does this mean the o2 sensor is bad? What do you guys think? I can't find any information on it. Thanks