I just bought an '84 RX-7, 12A, 5 speed. I don't know if it's an SA, FB, or WTF? cause I haven't figured out this vin number business. The car has a little miss at idle but runs well throughout the rest of the powerband. It needs a piece or two of the exhaust (you can hear the ticking and the exhaust is loud). Would the exhaust leak cause the miss, or does it need new plugs/wires or carb work? It's been sitting for about two years. Could it also be this carbon buildup all you rotary folks talk about?

Sorry for the noob questions. I have a '78 Chevy Nova with a big block/4 speed and these fun little japanese things aren't my area of expertise.

Kev

 

Welcome to the club.

You have a FB, FB=81-85 SA=79-80. Im sure others will ring in to help you with your other questions so have fun with your new Rx. You can try simply using some carb cleaner but your carb still might need to be adjusted.

And the few peices missing on the exaust could also be the cause. But what pieces do you think you are missing? Is the exaust stock?

Good Luck

 

Welcome to the forum.

First thing you need to do is a full tune up. Plugs, wires, oil, fuel filter, cap and rotor, etc. If it's been sitting for two years, the last thing you want to do is trust whoever owned it before. After you give it a good tune up, if it's still missing a bit, the guys around here can steer you in the right direction.

 

I believe the pipe coming down to the cat is rotted out, but no way to confirm until I get the car in the air. The whole car is bone stock.

Kev

 

If you don't have emissions testing in your area, check out the FAQ section for instructions on how to remove the "rat's nest". This will eliminate the tube that goes to the cat.

When you are picking up your supplies for the tuneup, grab a can of Seafoam and dump it into your gas tank. I try to do this periodically with about 1/8 - 1/4 tank of gas to clean the motor out and free up the apex seals. Smooths the idle out a bit too.

Welcome to the forum, and good luck with your new obsession.

 

HA!! Obsession is an understatement. Its more like a sickness! AND I LOVE IT! (Begins deep evil laugh)...............................

Oh and welcome to the forum. You will ike it here.

 

I second the rats nest removal, as you may have the old shutter valve problem which affects both idle and surges at constant throttle. Rats nest will remove the problem altogether, either way its an easy fix.

Welcome to the dark side.....

 

Link

https://www.rx7club.com/showthread.p...=shutter+valve

 

It backfires on WOT shifts. The tach isn't working either. Where is the connection for the tach at? It's on the distributor on my Chevy's, no idea on the rotary's.

Do the FB's have points? I see double external coils along the fender well with wires over to the distributor. It does run pretty good though. Drives straight and rips hard in 1st and 2nd.

Kev

 

With the back firing and tach not working, it sounds like your trailing ignition took a dump. The tach signal is pulled off the trailing side of the ignition. It is a bullet style, single wire connector at the dizzy. With the engine running, trace a trailing, top, plug wire back to it's coil, pull the wire off and see if you are getting spark.

Backfiring and flames are common on a rotary with the cats and emissions removed.