mesallem

Was driving my car on the high way and heard a loud pop come from the engine bay. 140,000 on the original engine. Intake, intercooler, m2 ecu and knight sport turbos installed. Afterwards engine sounded poorly under 3000 rpm, also smokes. This was a year ago, since then i stopped driving it and left it in the garage. Finally I have some time to look into it and I'm wondering if it is common to hear a pop from the engine when you blow an apex seal. Also, the car doesn't want to start anymore, could this be due too flooding? Will ATF work? My one problem is the pop and what it could be. IT was a very LOUD pop. Thanks.

Jay7 Nyc

iTrader: (3)

Where was the vacuum at after you heard the pop at idle? Stock motor should be around 18-15lbs of vac at idle. You can try pouring alil ATF into the LIM or marvel mystery oil.. Best bet is to get a compression test done either from a local mazda dealership or you can get a compression tester at sears for around 40bux.. With 140k on the original motor I will say that someone took good care of that motor up until then and I wouldnt doubt the motor went on you.. If you think its flooded remove the bottom plugs pull the egi relay and crank her for 3times 10secs each time, replace plugs with new ones and try cranking her make sure your battery is holding a good charge..

P.S: Just to be on the safe side, make sure that MAP sensor is connected right, its on your firewall on the driverside has a clip and lil silicone hose on the bottom make sure both the clip and hose are connected..

mesallem

What is the MAP sensor? Battery is good, just replaced it. After it happened, I pulled the ECU and went to get it checked out but didn't have time to. I'll run a compression test tomorrow. What numbers should I hope for with the sears compression tester?

2FAST7S

[QUOTE=mesallem]What is the MAP sensor? Battery is good, just replaced it. After it happened, I pulled the ECU and went to get it checked out but didn't have time to. I'll run a compression test tomorrow. What numbers should I hope for with the sears compression tester?[/QUOTE

its a black box about an inch long and three quarters of an inch wide with an electrical connector on the right side and a vaccum line going into the bottom of it. It senses the engine's airflow.

Before you go out and get the compression tester, just pull the egi fuse and one of the plugs. Have someone crank it and listen for 3 even swishes on each rotor. If you dont get 3 similar sounds youre missing an apex seal somewhere. A blown rotary will sometimes start and essentially run on 1 rotor but you can tell its blown cause it doesnt want to idle, makes little power and has a lot of loud backfires...thats if it starts. A few months ago we had a similar problem and we thought it was just flooded but it was indeed blown.
Good luck with it! and I really hope its not blown!!!then again street porting?? lol

Jay7 Nyc

iTrader: (3)

Sears compression test you want over 85PSI on both rotors.. Do a search on the forum for map sensor someone has to have a picture on here.. It is on your firewall its the only black little square box on your firewall that has a clip and small hose underneath on the driver side, hose is coming from the UIM..

BlueTII

There is a compression test "how-to" on our website at www.banzairacing.net , this is using a standard compression gauge.

If it has been sitting for a year your gas has degraded unless you added some stabilizer.

When engines blow they don't typically make a "pop" , they usually just start running really poorly. An actual "pop" is usually an intercooler coupler coming off under boost, but this would not account for your bad idle under 3k rpm.

Take the compression reading, while you are there change your plugs. Let us know what the readings are.

quicksilver_rx7

That's unbelieveable!!

Tim Benton

iTrader: (1)

actually, my first engine did make the pop noise, like a loud ballon when the apex seal let go. I think it was binding and when it finally let go, POW.

Tim

chinoflyer

iTrader: (1)

mine makes a pop sound when my intercooler coupler comes loose under boost. it was more like popped off the pipe. Just my 2 cents, but i am sure you already check that out, right???