my rx7 used to start up just fine but in the last week started to act up. I would have to hold the key in the start position longer and longer for it to start up and now it wont even start. So, the only way to start it is popping the clutch. My battery is fine and so is my alternator, what else can it be? Another problem that could possibly be related is whenever i come to a stop or let go of the throttle my battery voltage drops? Any ideas?
thanks

 

you might have lost compression. I hear that makes engines harder and harder to start as they get weaker. You might also need to clean the injectors.

 

What does the voltage drop to when you let off the accelerator? How does cranking sound, does it seem slower/weaker than usual?

 

when was the last time you changed your spark plugs and spark plug wires?

 

I have changed my spark plugs w/in the last year, as far as the wires though, who knows? As far as the voltage drop, that depends on my accessories. If I have my radio, heat, and lights (including fog lights) on then it will drop under 10. My radio will keep turning off. If i just have my fog lights on and that is it, then voltage will stay at about 12 or just under. It peaks at nearly 14 though when im driving.

 

The battery was tested at autozone and came up good. I also tested the alternator by disconnecting the positive terminal while the car is running and it continued to run. When I turn the key i can hear the engine rolling over, but doesnt roll over fast enough to start the damn thing. Like i said before, a week ago it started acting up and i would have the key turned in the start position for 5 seconds, a couple days later 10 sec. and so on to where now it wont start. Hopefully this can help you guys help me. thanks

 

Maybe the starter motor?

 

That is a great way to smoke out the regulator on a Alt. Pretty much guaranties that you wasted the integrated regulator, or at very least put it on the path towards death. You could do that old disconnect to test method back in the old days before integrated voltage regulators, but you can burn out alts or even whole electrical systems do that on a modern alt.

If at any point the voltage gauge on the dash is reading less than 12.6 volts then your alt is not producing sufficient voltage and amperage to even charge the battery.

So based on that, I say you had a bad alt, (which is even worse now) and possible bad engine grounds or alt connections.

As far as the hard starting, yeah at very least I would replace the plug wires.

 

From what he said, I'm guessing his hard starting is caused by his bad alt not charging enough. Though, replacing plug wires is always a good idea.