syman

Hi,my name is Symon im having an 2004 mazda rx8 manual 6 speed(Living in Canada) 2004 with 135000km,engine was replaced at 100000km with sparks plugs and coil pack,i had this car since 120000km with no issue,2 day early,i whent home,park car,one hour after,start my car,check engine occure an when i try to drive my car,it couldnt get above 5000rpm and absolutely no power from engine(hard to get above 60km per hour).No choice to park it. I have an aftermarket OBD2 fault code reader,no fault stored(check engine always on).To make sure the tester fonction properly,
i unplug throttle and read code,now getting fault for throttle,so i know my machine does read fault.)I clear fault,start car again,was able
to run engine good for the first gas pedal press,after getting again on failsafe mode with check engine light on.when i do i diagnostic request on sensors i notice when the car come in the safety mode,throttle not opening more than 18% at full gas pedal pressed.I also notice there is condensation in my engine oil dipstick,so i replaced engine oil(no trace of water in old engine oil and no trace of engine oil in coolant expension bottle,also coolant level always at same level,no coolant consumption.)erase fault again,check engine still there and protection mode active.I gave it up.Yesterday,no problem,i drove my car for a 45 km. trip without any issue with good power,so i tought the problem might by caused by the condensation in engine oil.Today,check engine came back at first start and power restriction mode occure.
Im prety sure its not a mechanical problem but more and electrical problem.
Can someone had this issue and help me with that problem please.
Thanks in advance for your advice.
Symon and my email adress is symon.mercier@live.com

dannobre

iTrader: (3)

Likely the MOP position switch needs a tweek It is the most common reason for limp mode

syman

Good morning Dannobre,sorry about my ignorance but what its the MOP
position switch and where it is.
Thanks again for your reply.
Symon

dannobre

iTrader: (3)

Metering oil pump

There are quite a few threads on this already so have a look around. It is the pump that injects oil into the rotor housings for lubrication. If the PCM doesn't like what it sees when it does the self test at startup it goes into safe mode

zoom44

if you have a check engine light then it will have stored a code. if your reader does not see a code it is not CAN compatible/ compliant. get the check engine light read and find the code

when ever i see a code after starting I think evap leak. one that sends you to limp mode would be a large leak like a failed vac pump not just the gas gap

dannobre

iTrader: (3)

Good snag ....my reading comprehension was low at that time

syman

Hi Zoom44,thank for trying to help me ,my OBD2 reader its CAN compatible and it does read fault,as describe above,when i create a fault by unplugging throttle valve or mass airflow,i get fault code for these sensor unplug and the engine running differently after,i think more its a particular fault that can only be read by Mazda scan tool.
Im havent work before on renesis wankle engine but i do know on piston engine,DMTL fault,evaporation,leak...dont make engine fall in engine protection mode.
I unplug the omp (or mop?)sensor and the engine its having same issue and
im still aint able to see fault.So i think im in the right direction.
Do there is a way to bypass it(cross wire,install a resistance...)
Thanks again for your help.
Symon.

zoom44

If you have a check engine light illuminated on the dash then there are only two reasons your scanner cant read the code- your scanner isnt fully compliant OR your PCM needs replaced

dannobre

iTrader: (3)

No way to fool it..the PCM expects a very specific response to the startup check. Mark the sensor position and Just turn the position sensor carefully a bit and try it again...if it doesn't work try the other direction a bit.....you should reset the PCM in between each try. Often this will work. Otherwise try and get a used pump from someone The sticker shock on a new pump is very harsh ( about 1K )

syman

Thanks again,when i will have time i will try to move the OMP.
Symon.

syman

HI guy.
I decide to wait to check for the check engine to make sure im looking at the right thing.Finally with the fifth scan i try i found fault;
-p1688 metering oil pump stepping motor /4 control circuit status ff(value above theshold)
abd
-u0073 can communication bus fault status ff
With these fault now what do you thing about moving adjustment of the mop
sensor.
Any advice.
Thanks in advance.
Symon