I have a 1987 RX7 and I just put a engine from another RX and It started right up. The only thing is it dosent stay on.

It starts up and runs at high idle for a few seconds and then goes to drop to low idle and just fades out.

I tryed to hold the gas pedal to prevent it from fading and it idles irratically (RPM bouncing all over the place, from 1200rpm ot 2000rpm) it cant maintain steady idle anywhere under 2000RPM.

If anyone has any ideas about how to fix this notorious fade out please tell me, I appreciate any help.

thanx
Nick

 

Sounds like a vaccume leak. Check all the hoses, and gaskets.

 

make sure your tps is connected and working.

B

 

I vote vacuum leak.

 

I'll 3rd that...

 

Thanks guys for your advice, I'll check it first thing in the morning !