Hi all, so my buddy just put a rebuilt N/A in his RX-7 and it cranks perfectly and sounds fine but takes awhile to fire. Once it fires, he has to keep revving it or it will die. We have checked BAC and TPS and more. Any ideas?

 

Now it won't crank at all..

 

If the starter does not turn over then check the Main fuse. If the wipers or turn signals work w/key to on then the fuse is good.

 

Yeah all the light work and everything. We changed the BAC and now it doesn't crank.

 

The lights are independent of the starting circuit and Main fuse. Just please focus on what was asked.

 

Sorry, meant lights as in turn signals.

 

If you're not sure, ask the forum instead of changing things blindly.
"and now it doesn't crank" ...you touched something and the fuse popped.
Check the Main fuse as said.

 

Does the car require the clutch pedal being depressed to start the car? And are you stating that the starter does not engage or it engages but does not start?

 

Well it was recommended on other threads so we assumed. The main fuse is fine.

 

Yes it requires the clutch in to start, and the starter is not engaging.

 

And this is an S4 ? I gather that the car has the factory alarm or not?

 

N/A and yes S4 and no he says it doesn't have a factory alarm

 

You'll find a Blue plug near the trailing coil and on one side of the plug will be a Black/Green wire, a Black/White wire and a thin Light Green wire. On the other side of the plug will be a U shaped jumper wire bridging the B/W and B/G wires to each other. W/key to start the B/G wire should have voltage and if it does then the voltage should pass to the B/W wire due to the presence of the jumper wire. The B/W wire then passes down to the starter solenoid to engage the starter. So, check for voltage on the B/G wire w/key to start and if that checks out then look for the voltage on the B/W wire.

EDIT: And the clutch needs to be depressed w/key to start.

 

Thank you for the help, we will try it.

 

If the B/G wire does not have power as suggested then you'll need to locate the Interlock Switch at the very top of the clutch. Don't confuse the switch towards the bottom of the clutch pedal as that is not the Interlock Switch which is used in starting the car. The Interlock Switch has but two wires, one Black/Red and the other Black/Green. W/key to start the B/R wire should have voltage (pedal does not need to be depressed here). If it does have power then w/the key to start and the clutch depressed the switch should pass voltage from B/R to B/G. If it does not then the switch is at fault. The two wires feeding the switch has a plug where a jumper wire can be used to bridge both of these wires and then the starter should properly turn over as designed.

 

Car cranks now. Now back to the question of why it won't idle lol

 

Did you adjust the idle screw?

 

If you have to fight the engine to keep it running you should check for vacuum leaks and the AFM to start with. The issue could also be contributed by problematic primary fuel injectors and improper fuel pressure.