Got CEL P2122 , how to repair or replace
 

P2122 APP sensor No.1 circuit low input ON 1 CCM ´ (See DTC
P2122 )

My car has been giving be starting problems, when cold it starts awesome, but with a little throttle problems, I have to keep it at 3000 rpms for at least 10 seconds so it stabbles normal at 1000 rpms,

I have replaced with Mazda the following ( all parts are brand new ) :

OEM 4 ignition coils - $130
OEM 4 spark plugs - $60
OEM 4 wire plugs - $70
OEM Starter - $128
OEM Battery - $115
OEM Cat - $833
OEM O2 Sensor - $63
OEM 3 Valve Sensors - $240

I took it recently to a Mecanic who's worked with rotary engines and also has worked on my car with tranny and a few other mods, and he advised that my primary or secondary fuel injectors are clogged and needed to be replaced, as you can see I have spent christmas with this issue and will really hate to keep spending if the problem is not solved , so if anyone has experienced P2122 and knows exactly whats the deal I'd appreciate the help guys... BTW reflash by mazda was done also...

Thanks

That code is for the Accelerator Pedal Position sensor.
PCM monitors input voltage from the APP sensor while the car is running.
If the input voltage is less than 0.3V, the PCM determines that the APP sensor input voltage is low.

Possible causes:

• APP sensor malfunction
• Connector or terminal malfunction
• Open circuit in wire harness

thanks Jon, how hard is it to replace ? and what part number am I searching for, believe me I'm a google fan and seem to not find any information of how to replace or repair this issue....

I already mentioned what the causes for that code is, you now have to troubleshoot from here.
Check the connector at the accelerator pedal.
If you want to rule out the pedal assembly, ask a local RX8 buddy to swap for his and see if it works (better than spending money on a pedal just to find out its not that).
Start checking continuity between the connector at the terminal and the PCM.

awesome Jon, thanks again will get back and post how the swap went... hope this gets solved ....

Good luck... hopefully this isn't one of those problems where a CEL is generated as a result of something completely different.
Wouldn't be the first time that's happened... this is why I recommend swapping parts before spending money.

Did anyone ever figure out this problem? I just got the same code, car won't rev over 3k. no power, it's in limp mode. I've ordered a new pedal assy but did someone find another problem in the wiring harness out else where?

Posted From RX8Club.com Android App

Hey I know this is an old post but I have the same p2122 code. Can you share your solution?

Hey! Did anyone get this done? :/ Mine is giving p2122 & p2127 ... I already tested some of the wires from the pedal. The letter D is grounding (It says to check D for a possible short to ground) I took everything apart All the wires But what I found is that the ground is coming from the PCM (4Y) I would appreciate If someone help. This is driving me crazy It’s my daily and have no money for a mechanic now :) Thanks!

​​​​​

https://cimg8.ibsrv.net/gimg/www.rx8...de7965c717.png
Here’s a screenshot from the Engine Diagnostic & Control

Currently in the same spot

Binsin ... check well every code (in case you have more than one) Just make sure there’s continuity in between the cables from the pedal position sensor to the ECU or PCM ... important (oil light might be a problem) If the oil pressure is low or the sensor is faulty the car might get into limp mode Well At least mine did ... not because of the light but something with the oil Metering pump. When almost giving up I took It off (the omp) and changed the stepper motor It had on It. After that no more issues The oil light illuminates sometimes but I think It’s the sensor in the oil pan | oil level is 👍... Hope that helps 🙏🙏🙏 good luck with that ... let me know If I can help