# limp mode



## artk (May 7, 2020)

I have a 2010 Altima that has gone into limp mode...I have replaced the MAF and the THROTTLE POSITION SENSOR I am also having a whining noise while its in limp mode any ideal on what could be causing this problem??? its a 2.5l


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## rogoman (Dec 16, 2004)

artk said:


> I have a 2010 Altima that has gone into limp mode...I have replaced the MAF and the THROTTLE POSITION SENSOR I am also having a whining noise while its in limp mode any ideal on what could be causing this problem??? its a 2.5l


One of the first things to do is perform an ECU code readout with a portable scan tool to see if any fault codes are set. The tool can be purchased at most auto parts stores or online at Amazon.com. Post the actual codes here on the forum so that we may be able to help you further. If there is one or more fault codes set, they can help point to the malfunction.


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## smj999smj (Jan 1, 2006)

Did you do the relearn procedure when you replaced the TPS?


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## artk (May 7, 2020)

smj999smj said:


> Did you do the relearn procedure when you replaced the TPS?


no I did not im not sure how to do that.


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## artk (May 7, 2020)

rogoman said:


> One of the first things to do is perform an ECU code readout with a portable scan tool to see if any fault codes are set. The tool can be purchased at most auto parts stores or online at Amazon.com. Post the actual codes here on the forum so that we may be able to help you further. If there is one or more fault codes set, they can help point to the malfunction.


I am getting codes P0420,P1002,P2122 and P2127


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## artk (May 7, 2020)

but the MAF has been changed and the TPS


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## artk (May 7, 2020)

artk said:


> I am getting codes P0420,P0102,P2122 and P2127


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## rogoman (Dec 16, 2004)

artk said:


> I have a 2010 Altima that has gone into limp mode...I have replaced the MAF and the THROTTLE POSITION SENSOR I am also having a whining noise while its in limp mode any ideal on what could be causing this problem??? its a 2.5l. I am getting codes P0420,P0102,P2122 and P2127


The Throttle position sensor is now part of the Electric throttle control actuator. Why did you replace the MAF and the Electric throttle control actuator? If the engine went into limp mode after you replaced the two said components, then those components may be faulty; are they OEM or aftermarket. When replacing sensors, always use Nissan OEM parts from a Nissan dealer; aftermarket electronic items generally are not reliable, don't last long, and many times are DOA.

For your info on the fault codes:
P0102 - An excessively low voltage from the MAF sensor is sent to ECM. Possible cause: Harness or connectors, intake air leaks, bad MAF.
P0420 - A three way catalyst problem. Possible cause: Bad three way catalyst (manifold), bad MAF, exhaust pipe leak, intake system vacuum leak, fuel injector leaks, fouled spark plug(s).
P2122 - Accelerator pedal position sensor 1 circuit low input. Possible cause: Harness or connectors, bad accelerator pedal position sensor.
P2127 - Accelerator pedal position sensor 2 circuit low input. Possible cause: Harness or connectors, bad accelerator pedal position sensor.


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## artk (May 7, 2020)

rogoman said:


> The Throttle position sensor is now part of the Electric throttle control actuator. Why did you replace the MAF and the Electric throttle control actuator? If the engine went into limp mode after you replaced the two said components, then those components may be faulty; are they OEM or aftermarket. When replacing sensors, always use Nissan OEM parts from a Nissan dealer; aftermarket electronic items generally are not reliable, don't last long, and many times are DOA.


i got the parts from the dealership and I replaced them after it went into limp mode not before I was trying to trouble shoot the problem
\


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## rogoman (Dec 16, 2004)

artk said:


> i got the parts from the dealership and I replaced them after it went into limp mode not before I was trying to trouble shoot the problem
> \


Check the engine harness grounding points for any oxidation and looseness. Check the charging system. A properly working charging system puts out about 13.2 to 15.0 volts, but this is a general spec, and the factory service manual should be referenced for the correct charging system voltage specifications for a particular vehicle. A battery should have a static charge of 12.2-12.6 volts. If a battery is not good, the charging system may not be able to charge properly. When a charging system is not charging, or overcharging, a lot of "strange" things can occur. It's not uncommon to see a multiple of stored trouble codes in the ECM memory. So, whenever a car is setting a multiple of trouble codes, idling funny or stalling, or anything out of the "norm," test the charging system before you start pulling hairs!

Try to fix the P0102 problem first; it might be causing the P0420.


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## smj999smj (Jan 1, 2006)

Any time you replace the throttle actuator, you have to do a relearn procedure. Start with that first. When you replace the MAF, you have to perform and idle air volume relearn. Today's cars are different; you can't just bolt on parts and go, anymore! Try these links:









Nissan Electronic Throttle Body Idle and Volume Relearn Procedure


Congratulations on installing your brand-new spectra premium electronic throttle body. In this video, we’ll be going through the required relearn instructions for your vehicle. But before we do that, there’s a few things we need to look at.



www.knowyourparts.com










Nissan Altima 2007-2012 Service Manual: Idle air volume learning - Basic inspection - Engine control system QR25DE for california







www.nialtima.com


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