I have a 91 RX7 convertible with an automatic. I bought it used and I got taken! The car is beautiful, almost mint condition but is for ever stalling out. Now I'm finding out that second gear is all but gone(I believe the previous owner would put it in second at lights with the foot on the brake and give it some gas to keep it from stalling out). A mechanic friend said this is a known problem with the 13b where the apex seal springs wear out after about 70k miles (mine has 96845) causing a loss of compression at low RPM's. From working with the car I'm leaning more towards a throttle body problem. When the car is started cold the idle is ~ 1500 RPM's. After it warms up and the automatic choke cuts out it will 'bounce' between ~ 450 and 1200, like it's searching for an idle and if you put it in gear without giving plenty of gas it will die. Also, as soon as you turn on the AC it dies, again unless you give it lots of gas.

Any help/suggestions is greatly appreciated!

 

I'm thinking a the BAC is the culpret, or TPS do a search for both and I'm sure you'll come up with a solution. As for the trans, I and almost everyone else here will highly recomend you do a 5 spd swap, you'll thank us after.

 

this sounds stupid..... but when i bought my fc, i had the same exact problem! i drove it like that for about 8 months... finally, i found what it was.... a vacuum line was pinched in between the throttle body and intake manifold! (it should run directly underneath the tb)... try seeing if you have a vacuum leak.... ??? sounds far fetched, i know.... but it is possible!!

 

That was my original plan but my mechanic friend that said he knew how to do it and would help moved away (and it turned out he didn’t know how to do it anyway). Since then I have not been able to find anyone that could tell me all the steps involved (maybe this is the site I should have been at all along?). But from what I have researched it doesn’t seem to be that easy. For one I have been checking for a cheap/wrecked donor car for some time now with no luck (I’ve seen plenty for $3000.00 plus). I say a donor car because I was told I have to cut the manual transmission mounts out of the host, I have to get the brain, the housing, engine harness, etc. If you or anyone else can help with places to get parts (and what parts are needed) and the process I’d love to hear from you. But before doing that I still need to make sure I have a good motor!

Thanks for responding!

Ted

 

Your mechanic friend sounds like he doesn't know anything. The springs do not wear out at 70K miles. My engine has well over 130,000 and still runs strong.

The stalling is probably caused by either a vac leek or the TPS or both. To earch for a vac leek just get the car to idle then spray carb cleaner (or water) around the TB and see what happens. If the idle changes any then you have a vac leek.

The TPS is a bit more involving and i can't remember exactly how to do it right now. Do a search for it.