Starting Issues 12A Turbo
 

Hello,

I've been having issues with starting my 1983 12A Turbo RX7. I have had it for over two months now, waiting for parts and replacing when I can. When I first bought the car, it started rough and ran but it had a really nasty backfire. Since then I've changed the fuel pump, fuel filter, igniters, spark plugs, spark plug wires, and most recently the injectors. Doing so did get rid of the backfire and it started running smooth, but now I really can't figure out what the issue might be as to why it wont start. Some days it would start, others it wont start. Attached is a video from it running yesterday. It was fine yesterday, so I don't understand why it would be any different. I haven't touched anything since yesterday. Any thoughts? Does anyone know any reputable shops that can help figure this out as well? I'm still trying to read up on what other causes of the issue could be, but I'm definitely lost at what else to look at.

Thanks for any help in advance!

I can't see your video. Is this an original Japanese turbo car, an English Elford turbo car or a home-made project?

Edit, just saw you were in Japan so I'll assume it's an original JDM car.

hi, it is an original Turbo Car

Dead battery or bad alternator?

Update:

brand new battery and tested the alternator. It is charging. So that’s good. Additionally I made a new ground wire to the battery because the old one was pretty worn.

I’ve got a spark plug tester and hooked that up along with a fuel pressure gauge. After managing getting the car started everything was running fine for a solid 7 minutes. Good strong spark and constant fuel. Everything sounding smooth and normal, no backfiring, and very responsive.

Moments after the car dies out of nowhere... spark was still strong and fuel still flowing. Thinking this is an ECU problem maybe not sending power to the injectors? Anyone have any thoughts?

perhaps a vacuum leak that is only evident when it comes off whatever version of a fast idle your computer has?

update 1-11-20

that might be the case. I’ve been checking vacuum hoses all week and replaced those that may have been cracked.

I did however, find something weird. I ended up disconnecting the fuel pump and the car started, without the fuel pump. It kept running until I guess all the fuel in the line was out.

So I plugged it in, wouldn’t start. Unplugged: It started and ran smooth, no unusual smells either. As soon as I gave power to the pump the car wanted to die.

That being said, I did a bit of testing because maybe the fuel pump wiring was not the right wire or something. So I make a jumper straight to the battery. Therefore it should be fine (for testing purposes).

Car still didn’t want to start as everything was connected. Took off the power to the pump, car started.

very very strange.