I was racing my 84 GS with a mostly stock 12A (except headers and exhaust) rx-7 the other day (I took a 2000 Eclipse off the line). When I got home and got out of my rx to open the garage it sounded like it was idling low. I looked at the tach and it was down around 550 or so rpm's. The next day it was again idling low as I drove it about 15 miles and on the way back it was begining to stuter a little when I would take off from a stop light, but not too bad, barely noticeable. Well, the next day it was definetely worse and as I drove it back home there was a definite problem with accelerating and idling, although it revs up fine once it's past the 2,000 rpm or so mark. I checked the fuel pump, plug wires, spark plugs, air filter, but it seems like it is something more in depth. I then checked the timing, which I had never done before but I assume I did it right. The timing mark was about 1" and a quarter away from the pin and I couldn't even advance the distributor to half way to where it wanted to be. But when I did advane it that way the idle started to come up. What could this be? Should I check the compression? Would the compression indicate a blown apex seal? I really appreciate any help I could get right now as I am in a huge dilema without a car for school and work. Thankyou.

 

Seems like I've read this elsewhere, but do the compression check next.

 

thats proble from me... ive sent about 10 threats tring to work out what the hell is is going on ??? ive got very much the same problem with the stutering when the car idles but ones i take off it is fine and there seems to be no power loss.. ive checked just about everything. i'm thinking it is electrical now but im not sure where to start

 

check for intake manifold leak.... use carb cleaner or brake clean.... poor idle and hesitation.... sounds like intake leak...check the rubber hose below the brake booster line on the intake manifold, near the back of the intake .... that hose is close to the exhaust , it gets really hot and cracks alot.... also check the shudder valve that could be bad too

 

check the ignition coils,
on the inside they maybe corroded

cant think of anything else right now but i will tell you that just checking the spark plugs and wires sometimes is not good enough,

just replace the stuff "mainly the plugs and dizzy cap and rotor"

set your old stuff aside and if it is not the problem the you can put your old stuff back on and set the new stuff aside and use it when you need it

 

I had an idle proplem on an "85" 12A. Turned out to be the corrigated metal hose that carries heat from the exhaust manifold to the air cleaner was disconnected.

 

He has a header, it would be disconnected.

 

Could've given your tired cap n' rotor the last ride of it's life. Try taking timing at the plugs for consistancy.

Stretched out the tiny kink in your throttle cable you did'nt know was there?

Could've even tweaked your throttle shaft a bit when you stomped her...Not everyones pedal stop setting is up to snuff.

None of these things are to worry over. Get the compression test done. This is the definitive test for apex damage. Nothing else will tell you for sure.

 

had a bad problem that seemed like what your having, try changing out the ignitors. Thats my $0.02