a couple days ago i was racing this one guy, so i was driving my car pretty hard. And then it made a funny noise and now my car is alot quiter. And i have about half the power that i use to. What is wrong?

 

u may have lost an apex seal. it will be very hard to start and will rev slowly since it will practically running on only one rotor. remove leading plug from the rotor housings one at a time so u can listen for the compression from the front and rear rotors independently, should blow air with each revolution if the seals are still there. this is what happened to '83 12a I used to run in my 3, lost an apex seal on the rear rotor.

 

so how do you do it exactly, you take out the leading plug and how do you listen to it. Do you start the car. How do you turn the crank without starting it.

 

disconnect the coil wires and spin it with the starter.

 

oh ya

 

I had to do this a few days ago lol
I:
1) pulled outh both egi fuses form the main fuse box in engine bay, and put on fuel cut switch (I dunno if necessary)
2) pulled out leading plug out of one rotor, got someone to crank it over for a bit and listen for 3 even pulses of air and regular intervals between the pulses.'
3) replaced the leading plug and did same thing with other rotor and listened for pulses of air and compare the intensity of the two. If a seal is gone there will be a skip in the pattern, if low compression in one rotor, one will sound weaker.....

you can also compare with a piston compression tester if U have one, it probably wont give you accurate number regarding compression but you can use to compare the differences (if any) between the rotor's seals.

Also check for spark... I had the same thing.. no power --> slow revs and it turned out to be no spark on leading plugs

I hope I got this right~!!!! (anyone feel free to correct me lol)

 

thanks man

 

Yep sounds like an apex seal to me

 

I think a compression test at Mazda dealerships costs about $75 these days. Their test gives you 3 readings for each chamber.. one for each rotor face.

It's expensive, but it would diagnose any chamber problems.