WanKeL FD RX-7

iTrader: (7)

Hi guys,

I had this problem twice in one month.

I arrive at the hotel in the parking lot and the engine began to run on one rotor. SHitty vacuum, engine shaking terribly, the car would barely move, smoking black like I blew an apex. I thought my engine was blow but after a few minutes it suddenly return to normal and I was able to get back from the states (carlisi meet) to canada with no problem.


Last night, starting the car, everything was ok. When I got that backwards, it did the same thing ... It was running really rough with black smoke in the rear and smoke coming from the exhaust manifold side in the engine bay. After a 10 min, it return back to normal once again and I have been able to go back to my house normally.

I wonder what it is ...

My spark plugs are new (9's), recent oil. The engine has about 15,000 KM. Vacuum -455 on idle at 850rpm.

Mods ;
downpipe
HF cat
catback
intakes
act clutch
11psi on sequential stock twins
power fc
avc-r
Greddy type rs bov

Someone has an idea, I'm really lost with this ...
Thanks,

Max

WanKeL FD RX-7

iTrader: (7)

https://www.rx7club.com/showthread.p...it+back+normal

looks similar to me (symptoms)

The first time I had my problem, the car was fully warmed up.

Yesterday night, the car was cold but I did'nt turn it off... So I don't think that's a flooded thing.

Max

phrost

iTrader: (14)

check your vacuum line to the map sensor (the one on the firewall behind the throttle body that says boost sensor on it)

WanKeL FD RX-7

iTrader: (7)

Thanks for your answer Jay. This is the first thing i checked and everything seems ok for the map sensor hose. Any other ideas?

WanKeL FD RX-7

iTrader: (7)

If this info can be helpful, the car has been tuned by steve kan with the old motor and the setup with new motor is the same.

I do have to change the clutch switch which I didn't have the time to do right now.

I'm boosting 11psi on the stock twins in sequential operation.

phrost

iTrader: (14)

Compression test engine, make sure you heat the engine to normal temp then pull plugs 15mins later and compression test. (put the car on jack stands first, to save time when u need to pull the plugs)
Inspect both leading spark plugs while you have them out, let us know of one rotor looks dirtier then the other.
How new are the spark plug wires? If you don't know order new OEM ones from Ray Crowe, or another mazda dealer...
Also, make sure all 4 spark plugs are getting consistent strong spark.

Hopefully the issue you are having is intermittent spark, most likely caused by bad spark plug wires or something else on the ignition side... But definitely compression test it.

WanKeL FD RX-7

iTrader: (7)

I will definately take the compression on it to be sure it's not the problem.

I do have some MSD spark plug wires on it since 2009. I think these spark plug wires have 9000 miles on them. Could they be done already?

Max

96fd3s

I think you have a crack in a vacuum line somewhere.

shmacklepap

iTrader: (15)

My car has been doing something similar for a while now, however only on start up's.

At first I thought it was a sticking injector, so I had them flow tested and cleaned. Results were good, before and after, put them in and still does the same thing.

I'm running "9's" as well, maybe it's an ignition problem?

WanKeL FD RX-7

iTrader: (7)

could the motor be toast?

Normally, if the motor was blown, it would run like crap all the time?

Mine runs pretty good except when i have this problem.

I'll check the vacuum lines of course.

Max