Limp mode causes???
06-30-2021, 10:38 AM
#26
Alright, yah I had it brought to the dealer for them to pull the code since our scanner wouldn't.
I will update everyone when I hear back.
Before I brought it over to the dealer, I did try disconnecting the OMP electrical connector and starting it. It was still doing the same thing, I cleaned the connector and put electrical connector grease same on it l. No change.
Thanks for the help.
I will update everyone when I hear back.
Before I brought it over to the dealer, I did try disconnecting the OMP electrical connector and starting it. It was still doing the same thing, I cleaned the connector and put electrical connector grease same on it l. No change.
Thanks for the help.
06-30-2021, 07:13 PM
#27
as Dan stated, the rise to max RPM indicates a runaway throttle and the DBW system would default into limp mode as a safety strategy precaution.
if it was the OMP it would generally require repositioning the external sensor or full replacement rather than just cleaning the sensor electrical plug.
if it was the OMP it would generally require repositioning the external sensor or full replacement rather than just cleaning the sensor electrical plug.
06-30-2021, 08:39 PM
#28
as Dan stated, the rise to max RPM indicates a runaway throttle and the DBW system would default into limp mode as a safety strategy precaution.
if it was the OMP it would generally require repositioning the external sensor or full replacement rather than just cleaning the sensor electrical plug.
if it was the OMP it would generally require repositioning the external sensor or full replacement rather than just cleaning the sensor electrical plug.
I was just explaining that when you first start the car you can rev it normally thru the whole rpm range, as in the car behaves normally for a few seconds before the ecu throws it into limp mode.
Mazda called me back though and they are waiting to have a rotary technician pull the code and diagnose it next week. Their regular techs were unable.
Last edited by Rx8me_; 06-30-2021 at 08:45 PM.
07-03-2021, 05:07 PM
#29
the misunderstanding is that I wouldn’t have expected anyone to intentionally be rev’ing their Renesis engine to 10k immediately after start up
but then again; noob … 😑
.
When I fire the car up it will rev to 10k rpm for a second or two. Then the computer throws it into limp mode and it won't rev past 5k rpm.
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07-03-2021, 05:53 PM
#30
Thanks anyways though.
What a community
07-04-2021, 12:28 PM
#31
Reset the ECU....
Start car..... see if it revs ok when it starts.
If it stops responding after about 10 sec it is going into limp mode.
Most likely reason is the MOP switch. If it is the actual pump it will throw a code.
Usually the DBW throttle will throw a code as well.
Easiest fix is a used MOP swapped in. A new one is serious cash and they don't usually fail.
If you are willing to play around you can move the switch adjustment point a bit at a time and reset and see if it starts working correctly. I have done that quite a few times on different cars and it will work if you are persistent. Only other reason for it is damage to the wiring... or plug. Check that out while you are in there
Start car..... see if it revs ok when it starts.
If it stops responding after about 10 sec it is going into limp mode.
Most likely reason is the MOP switch. If it is the actual pump it will throw a code.
Usually the DBW throttle will throw a code as well.
Easiest fix is a used MOP swapped in. A new one is serious cash and they don't usually fail.
If you are willing to play around you can move the switch adjustment point a bit at a time and reset and see if it starts working correctly. I have done that quite a few times on different cars and it will work if you are persistent. Only other reason for it is damage to the wiring... or plug. Check that out while you are in there
07-04-2021, 04:28 PM
#33
Reset the ECU....
Start car..... see if it revs ok when it starts.
If it stops responding after about 10 sec it is going into limp mode.
Most likely reason is the MOP switch. If it is the actual pump it will throw a code.
Usually the DBW throttle will throw a code as well.
Easiest fix is a used MOP swapped in. A new one is serious cash and they don't usually fail.
If you are willing to play around you can move the switch adjustment point a bit at a time and reset and see if it starts working correctly. I have done that quite a few times on different cars and it will work if you are persistent. Only other reason for it is damage to the wiring... or plug. Check that out while you are in there
Start car..... see if it revs ok when it starts.
If it stops responding after about 10 sec it is going into limp mode.
Most likely reason is the MOP switch. If it is the actual pump it will throw a code.
Usually the DBW throttle will throw a code as well.
Easiest fix is a used MOP swapped in. A new one is serious cash and they don't usually fail.
If you are willing to play around you can move the switch adjustment point a bit at a time and reset and see if it starts working correctly. I have done that quite a few times on different cars and it will work if you are persistent. Only other reason for it is damage to the wiring... or plug. Check that out while you are in there
Thanks, I believe it is the MOP then; is there anyway to tell if a used MOP switch/MOP unit is in working condition?
I have browsed around and found that they are in the $1500.xx range; which I'm willing to pay.
I was offered a used complete MOP with lines on the forum for $125; but I also don't want to waste my time waiting on a used one and finding out it's no good and having to buy a new one anyways.
Anything to look for or any input when looking at a used MOP?
Rx8's are not that common in my area finding a parts car is difficult.
07-06-2021, 02:27 PM
#34
Reset the ECU....
Start car..... see if it revs ok when it starts.
If it stops responding after about 10 sec it is going into limp mode.
Most likely reason is the MOP switch. If it is the actual pump it will throw a code.
Usually the DBW throttle will throw a code as well.
Easiest fix is a used MOP swapped in. A new one is serious cash and they don't usually fail.
If you are willing to play around you can move the switch adjustment point a bit at a time and reset and see if it starts working correctly. I have done that quite a few times on different cars and it will work if you are persistent. Only other reason for it is damage to the wiring... or plug. Check that out while you are in there
Start car..... see if it revs ok when it starts.
If it stops responding after about 10 sec it is going into limp mode.
Most likely reason is the MOP switch. If it is the actual pump it will throw a code.
Usually the DBW throttle will throw a code as well.
Easiest fix is a used MOP swapped in. A new one is serious cash and they don't usually fail.
If you are willing to play around you can move the switch adjustment point a bit at a time and reset and see if it starts working correctly. I have done that quite a few times on different cars and it will work if you are persistent. Only other reason for it is damage to the wiring... or plug. Check that out while you are in there
I still receive the same results.
Thanks, I appreciate your input and time.
Would anyone have a used Good Working Condition OMP? Or be able to point me in the direction to someone?
Best Regards
07-23-2021, 04:20 PM
#35
Confirmed MOP failure
Reset the ECU....
Start car..... see if it revs ok when it starts.
If it stops responding after about 10 sec it is going into limp mode.
Most likely reason is the MOP switch. If it is the actual pump it will throw a code.
Usually the DBW throttle will throw a code as well.
Easiest fix is a used MOP swapped in. A new one is serious cash and they don't usually fail.
If you are willing to play around you can move the switch adjustment point a bit at a time and reset and see if it starts working correctly. I have done that quite a few times on different cars and it will work if you are persistent. Only other reason for it is damage to the wiring... or plug. Check that out while you are in there
Start car..... see if it revs ok when it starts.
If it stops responding after about 10 sec it is going into limp mode.
Most likely reason is the MOP switch. If it is the actual pump it will throw a code.
Usually the DBW throttle will throw a code as well.
Easiest fix is a used MOP swapped in. A new one is serious cash and they don't usually fail.
If you are willing to play around you can move the switch adjustment point a bit at a time and reset and see if it starts working correctly. I have done that quite a few times on different cars and it will work if you are persistent. Only other reason for it is damage to the wiring... or plug. Check that out while you are in there
Hey, I just wanted to give everyone an update; finally recieved the car back after having Mazda Scan the CEL (took them a whole damn month) ☠️
CEL= P1688 Metering Oil Pump Stepping Motor #4 Control Circuit Failure.
I picked up a used S1 MOP along with a SOHN adapter Kit. Hopefully have her back up and running soon.
Thanks 😊
08-29-2021, 05:53 PM
#38
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Limp mode
it’s barely getting up to 30 mph and engine sounds a bit quieter when revving it’ll go to 4K max it’s like the air pump valve is stuck shut but sounds like bad omp or throttle body cause no matter how much gas it’ll move at the same speed
08-29-2021, 06:09 PM
#39
Connect the battery again, then start it again but as soon as it starts press the gas to see if it revs past 4k. It should rev past 4k for a second or so, until the ecu talks to the Oil Metering Pump. Then the ecu will throw it into limp mode with the rev limiter approximately 4k.
New MOP is $1600.xx USD
09-16-2021, 05:46 PM
#40
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A different kind of limp mode? Not omp???
Sorry for the new post. I have been refering to the forums for some time on how to fix my rx8. Lets start at the begining. Got the car and i changed out the coil packs spark plugs and wires.
The car then threw codes telling me the air pump was malfunctioning and not operating so i deleted the air pump and deleted the cat. I am in montana where i can get away with it.
Then the car threw a code for the transmission torque converter was stuck open. I changed the fluids.
Now and again during all of this the car will go into limp mode after driving it and running it for a while, when i stop and try to start again it is in limp mode. I have to wait 20minuites ish before i can start it again and it will no longer be in limp mode.
Resetting the ecu does not help. Disconnecting the battery does not help. I took the censor off the omp and it wasnt stuck at all. Cleaned it anyways but the issue persists.
I am not sure if changing the fluids on the tranny has helped at all as i have not been able to check if it threw the code again.
In short i am no longer sure what is causing the limp mode or how to fix it. When searching the forums there is allot of arguing and pointless info that normally is unrelated to the origional topic. Please help me, i love this car and am trying crazy hard to get it running right.
The car then threw codes telling me the air pump was malfunctioning and not operating so i deleted the air pump and deleted the cat. I am in montana where i can get away with it.
Then the car threw a code for the transmission torque converter was stuck open. I changed the fluids.
Now and again during all of this the car will go into limp mode after driving it and running it for a while, when i stop and try to start again it is in limp mode. I have to wait 20minuites ish before i can start it again and it will no longer be in limp mode.
Resetting the ecu does not help. Disconnecting the battery does not help. I took the censor off the omp and it wasnt stuck at all. Cleaned it anyways but the issue persists.
I am not sure if changing the fluids on the tranny has helped at all as i have not been able to check if it threw the code again.
In short i am no longer sure what is causing the limp mode or how to fix it. When searching the forums there is allot of arguing and pointless info that normally is unrelated to the origional topic. Please help me, i love this car and am trying crazy hard to get it running right.
09-16-2021, 06:57 PM
#41
How did you set the position sensor on the MOP? If it is the wrong place you will get limp mode. Have you tried changing the position and resetting ECU to see if that helps? You might need to try it multiple times.
To confirm if it is in limp mode.. reset the ECU and the throttle should work for 5-10 seconds before it stops working. If it doesn't do that you likely have another issue
To confirm if it is in limp mode.. reset the ECU and the throttle should work for 5-10 seconds before it stops working. If it doesn't do that you likely have another issue
09-16-2021, 07:03 PM
#42
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How did you set the position sensor on the MOP? If it is the wrong place you will get limp mode. Have you tried changing the position and resetting ECU to see if that helps? You might need to try it multiple times.
To confirm if it is in limp mode.. reset the ECU and the throttle should work for 5-10 seconds before it stops working. If it doesn't do that you likely have another issue
To confirm if it is in limp mode.. reset the ECU and the throttle should work for 5-10 seconds before it stops working. If it doesn't do that you likely have another issue
I just closed it and set it back 10 degrees.( 10 degrees open) Resetting the ecu rn and waiting for it to completely cool before trying again.
09-16-2021, 08:13 PM
#43
When you pit the switch back on did you set the switch in an active position? The switch should have some rotation when it is installed. It shouldn't be passive when you set it back up.
It's been so long since I did one... but carefully turn the blade on the pump so it stops and then put on the switch with a bit of rotation and center it. Then to get it working slowly turn it a few degrees either way and reset ecu and see if it works.
Problem is I can't remember if it was clockwise or counter clockwise that i turned the pump before I put the switch on. I think it was clockwise... but ??
It's been so long since I did one... but carefully turn the blade on the pump so it stops and then put on the switch with a bit of rotation and center it. Then to get it working slowly turn it a few degrees either way and reset ecu and see if it works.
Problem is I can't remember if it was clockwise or counter clockwise that i turned the pump before I put the switch on. I think it was clockwise... but ??
09-16-2021, 08:32 PM
#44
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Ok did not know the pump blade needed turning.
from what i understand clockwise closes the pump and counter closes it.
So to clarify 1 i need to turn the pump blade closed. 2 then seat the sensor. 3 reset ecu and try to run the car. Then if it goes into limp mode after 5-10 seconds turn the sensor a few degrees towards open and start step 3 again?
Thank you for your help. If this info was already out there it is burried in the internet.
from what i understand clockwise closes the pump and counter closes it.
So to clarify 1 i need to turn the pump blade closed. 2 then seat the sensor. 3 reset ecu and try to run the car. Then if it goes into limp mode after 5-10 seconds turn the sensor a few degrees towards open and start step 3 again?
Thank you for your help. If this info was already out there it is burried in the internet.
09-16-2021, 09:49 PM
#46
I have it posted on here somewhere; I always found starting full CCW (looking directly at the OMP sensor) and the rotating bit by bit in the CW direction worked best as far as activating it went. Mine adjusted from the factory was a lot closer to the full CCW position than CW. Whether there's any advantage/disadvantage to the actual position I'm not sure of.
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Last edited by TeamRX8; 09-16-2021 at 09:53 PM.
09-17-2021, 08:06 PM
#47
Weekend Warrior
Similar experience as Team on my old engine. OMP was happiest just a few degrees back from full CCW. Did a few thousand km fine like this before old tired engine let go and was replaced.
I made sure to keep old OMP without adjusting it at all just in case i need it later on. These cost big $$ to replace.
I made sure to keep old OMP without adjusting it at all just in case i need it later on. These cost big $$ to replace.
09-19-2021, 12:29 AM
#48
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This is by far the dumbest part i have ever encountered. Why does it move when it needs to be in one particular position, and why is it under the damn car. I love the rotary and this car but damn.
Ok now that i got that out. I have been all over the board with this sensor. I have been at it a few days moving it a little bit at a time to no relief.
i started by turning the **** to the left (counter clockwise) and then placing the sensor on then moving it a little bit at a time. Is there something im doing wrong this sucks lol.
Ok now that i got that out. I have been all over the board with this sensor. I have been at it a few days moving it a little bit at a time to no relief.
i started by turning the **** to the left (counter clockwise) and then placing the sensor on then moving it a little bit at a time. Is there something im doing wrong this sucks lol.
09-22-2021, 12:44 AM
#49
it moves because it needs to be adjustable to some degree, but generally speaking that typically only occurs if the MOP was removed and reinstalled
It could just be bad which that sensor itself is not replaceable, or it might just be something else, especially if it has an auto trans. It will probably take a professional 10 mode OBD2 device to determine the issue.
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It could just be bad which that sensor itself is not replaceable, or it might just be something else, especially if it has an auto trans. It will probably take a professional 10 mode OBD2 device to determine the issue.
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