So i dont wanna post the same thing i did in the below thread. Im trouble shooting the gsl-se. if the car has not ran for a week or so. when u hook up a compression tester its still suppose to read something correct? My front rotor got 0 and my rear like 30. i believe my air flow meter was bad and caused this.

 

to get good compression, it has to be running right, if you have flooded it, compression will drop.

 

but would it drop to 0?

 

Why would being flooded have anything to do with compression, other than to maybe increase it, because there is fluid to help seal loose seals?

If you are testing compression the engine better not be running at all (afaik anyway).

I just compression tested a motor with a Mazda tester. I did the test both hot and cold. There was a small difference (about 0.5 kg/cm2=7psi), with cold being lower.

I also tested the motor hot with the throttle wide open and closed. In that case the compressions with closed throttle was about 1.4psi = 20psi less.

Mazda says test hot and at WOT. If the car doesn't run and you have to test it, cold won't make that much difference. If it is bad or marginal you will know it. Testing with the throttle closed will introduce a much bigger error.

Also the cranking speed makes a big difference. Mazda says you need to be at 250 rpm. There correction curve is from 200-300rpm. Basically that means that it has to be turning pretty fast on the starter, since you can't read 250rpm on the stock tach. If the battery is low and the engine isn't turning very fast, the results will be significantly affected.

And also it shouldn't show zero, especially if you are using a non-Mazda tester. Especially if it was running a couple of weeks before.

I didn't see our other post, so don't know what other info you gave there that will show that I am way out in the weeds on my response.

Carl

 

Oil is what helps seal the combustion chamber, not gas. Too much gas washes the oil away and will reduce compression. Its well known with these engines when they flood compression seems to drop. Its also why people use oil of some kind or ATF to help boost compression when trying to start a flooded rotary engine. Try it yourself in a piston engine, add some oil and voila, compression comes up, add gas and it drops back down.

As for dropping to zero, a bad MAF wouldnt cause that...

~T.J.

 

The Mazda RE tester has a mode where if your rpms didn't quite make 250, you can press and hold the No1/no2 button and it will calculate the compression @250. Just did two Fe1 engines in the last week at the shop with that tester. An awesome piece of hardware.

As for your compression issues my friend, i'd recheck after getting a can of Zoom power engine cleaner from your local Mazda dealer. Take out your sparkplugs, spray some of it into the ports directly , then turn the crank by hand and repeat several times. Then, reinstall your plugs, find a vacuum port on in intake, and with the help of a friend, spray that cleaner down into the engine with the throttle wide open with the engine cranking . Do it several times for about ten seconds each and repeat twice. Then let the vehicle sit for a few hours while it does it's magic. ( please note you have to disable the fuel and spark system in order to do this properly and generally the engine should be hot, but in your case you don't have much of a choice. lol)

I've used that cleaner many times on customer cars that had been flooded multiple times and that were carboned up. Makes a hell of a difference.

Outside of that, you need to make sure you have air, fuel and spark. basic checks for a no start. Good luck and let us know how it turns out.

 

WTF??

 

did the small atf trick yesterday and put n a new battery and its still a no go. my tach was bouncing all over the place for a few. i just dont know how both rotors could blow at the same time. its like its not even trying to catch to start up at all.

 

dude, it carbon locked, see it a few times, get the mazda stuff, flood the engine with it and see if do what is is going to do.......................free up the carbon. Spin it over with the plugs out. clear the engine. 20 seconds cranking does it. oil the plug holes(leading) with an oil can( hand pump) rotate the e shaft and do it again, both 1 and 2 it will take 2 e shaft revolution to coat every thing. put the plugs in and start it up.

It will smoke a lot, keep it at 2500 for a while. now that it is running, get some seafoam and do the seafoam treatment on it.. as for the tach all over the place mine did this when the battery was low when cranking

 

^ Snivley, I basicly said that already. lol.

 

well what explains he 0 compression on both rotors?

 

The validity of your test. what kinda tester did you use? I would find it hard to believe that you have Zero compression unless you removed both leading and trailing plugs. lol.

 

it showed that. but i have gotten it running. neighbors called the fire department lol. atf was everywhere. Car idles fine now and compression test showed 90 on both rotors. the problem is now as soon as i try to drive it.it starts bucking and hesitating big time. like i give it full throttle and it barely wants to take off

 

Fuel pressure, spark, timing, what's everything doing?

 

its all working from what i can see. im concentrating on the spark as of now. i will update if i can figure something out

 

ok so car is running. as soon as i try to give it full throttle even when its in neutral. it bogs out. i basically have to play with the pedal. its like its either getting not enough gas to stay running or takin it way to much gas. any ideas?