what you need to do is use your compression tester and press the release button on it because you need 3 readings from each rotor unlike a piston motor. You dont want it to stay on the first reading it gets. put it in the top plug of each rotor. Take out the fuel pump relay in the thin footlong case. then have someone try to start the car with the throttle floored all the way and watch the gauge. you want to have almost the same reading 3 times. I am not sure that you have a blown motor but it does sound like it. Either that or your cats clogged or an injector is stuck open. I dunno just do the compression test and you can work from there. sadly this diagnosing what broke is usually very easy, preventing it is tough

 

Ya a very easy way on doing this, is remove ALL your plubming and release the tension on all the belts, to the point where you can turn the crank by hand. Then have someone turn it slowly as it goes by each rotor face to check each face's compression. I did this and works perfectly.

 

ok, i will try that. I actually just bought an HKS downpipe. I was planning on buying the performance items (ie. fuel system upgrade, turbo's, y-pipe, fmic, etc.), and having the motor rebuilt then putting everything back in at once. How much does a rebuild w/a street port usually cost?

 

A reman is 2200 so add w/e porting to that and thats it.

 

is it cheaper to just have mine rebuilt?

 

If a coolant seal is shot or an apex seal is blown then thats what you pretty much have to do.

 

well, i mean as opposed to buying a reman, would having the motor rebuilt w/a street port be cheaper than buying a reman and having it street ported?

 

Rebuilding your current one would be a whole lot cheaper. But that assumes that all your internals are reusable. If your rotor housings, rotors, etc are out of spec you'll need to purchase those.

KD Rotary in PA (where I had my rebuild done) recommends just buying a reman to start with. They say most of the time enough of the internals of the motor need to be replaced that it's easier to get stuff that you know is in spec, as it would be with the reman.

 

ok, well i think i'm going to research some pricing and just replace/rebuild my motor anyways since it has 102k on it.

 

ya...i had the exact same prob...
got a reman shipped for 2500...duno what a rebuild costs...but hey....
replace some gaskets, checked turbos, silicone hoses, etc and shes almost done

 

well, I have a wholesale account with Mazda, so I will call them Monday and find out how much I can get the reman's for.