On the '90 GXL I picked up recently I noticed that the hose that goes to the air pump is missing? Will that affect my idle much when I turn the engine on and just let it sit? Im trying to get to the heart of the issue on this RX-7 Becuase most times when I crank it up it doesnt have a problem starting, it has a hard time staying running. After about 3-5 seconds it cuts off. On the times that the motor does not shut off the idle is so weak it's almost a whisper! But besides that hose missing the only other thing odd I noticed about the engine bay was the missing TPS and the A/C Compressor was removed and one of the A/C lines was mangled on the end.

 

the rubber hose? no, not really, all i have on it is a small air filter/breather because i took out the factory air box. didnt cause me any problems. So I doubt that is the root. But you do need a TPS. lol

 

Cool, gonna get that at least tomorrow. I just have to figure out how to properly install the thing the right way!

 

The hose b/t the airfilter assy and the airpump cannot effect the engine running.

The TPS missing will cause a bad idle. A bad/erratic idle if memory serves.

Get a TPS, set it per the FSM, then set the idle speed per the FSM.

 

I havent had a chance yet to do the proper adjustments yet, BUT I installed it so far and now the car will rev over 2K and the check engine light didnt come on after a fwe cranks. BUT it still wont hold an idle on its very well. The first couples times I cranked it up it died when I let off the gas and after the third time it stayed running but the idle was deathly quiet, and weak. Sound like Im on the right track perhaps though? I gotta bust out my FSM and get this stuff adjusted properly. I pray this car's motor is good. Black on Black leather S5's are tough to find in one piece around here.

 

A real low idle might indicate that the BAC isn't connected up or has an open wire or???? Usually if the ECU sees idle speed below 750 rpm or so, it'll drive the BAC to up the rpms by injecting more air into the intake.

It sounds like a combination of a BAC not working AND an incorrectly set idle speed. Timing should be checked before setting the idle just to be on the safe side.