Limp Mode and FI
 

2011 NISMO with GTM Stage 1 SC w/custom tune

I have encountered limp mode 5 times over the span of about 3-4 months. I opened a thread in the tuning section a while back but did not get a lot of responses.

Has anyone else who is FI'ed gone into limp mode and what was the cause? I have an appointment this Friday with the shop to troubleshoot but I am asking for advice from the forum as well. My shop and I initially thought this was a clutch related issue, but now leaning towards an erratic MAF reading.

Limp Mode #1
This was on a 2nd to 3rd shift, full throttle, and instant limp mode, happened on a ramp entering the freeway. Pulled over and on a restart, the car was fine and I drove on.

Limp Mode #2
This was also a 2nd to 3rd shift, full throttle, passing a slow moving car, also happened on a ramp entering the freeway, limp mode instantly on the shift. Pulled over and after several restarts the car was fine.

Limp Mode #3
This was a 3rd to 4th shift, full throttle, merging onto a freeway. Pulled over and it took several restarts before the car would rev normally.

Limp Mode #4
My tuner was able to duplicate the problem last Friday while doing several different shift combinations and full throttle accelerations. He initially thought it was clutch related, but there is very little if any slip. He suspects something causing an erratic MAF reading or some other sensor.

Limp Mode #5
This one happened on the commute home today. I was full throttle in 4th at about 6.5k, the revs hit a wall and stopped. I was in limp mode. I pulled over and on a restart the car was fine all the rest of the way home. This is the first time I hit limp mode and was NOT shifting the gear box. This time happened under full throttle acceleration only.

I am NOT getting a CEL, but Cipher pulled this code:

-------- ECU --------

One code found!
**********
P006A

This code is MAF related. I am going to log the commute home tomorrow and hopefully get an entire log when it happens if I can duplicate it again.

I appreciate any ideas on a fix.

You should pull the maf sensors out and clean them with electrical cleaner and see what happens. Dirty maf sensor can do that

Simple Fix. Your tuner should be able to take care it. BTW, this code was taken care of on the original tune. Most likely it was left out when you got your custom tune done.

Sam

A p006A is:

"A difference exceeding the specified value develops between a value transmitted from the Manifold absolute pressure (MAP) sensor to ECM and an estimated intake pressure of intake manifold calculated by ECM based on Mass air flow sensor signal"

Sounds like it could be an issue with the MAF/MAP scaling. Are you using factory MAF sensors or the upgraded UpRev units? Are you utilizing a higher pressure MAP sensor?

If its not found in the tuning:
1) Harness or connectors
2) Mass air flow sensor
3) MAP sensor
4) Evap pressure sensor
5) Intake air leaks
6) Intake air temperature sensor

Make sure everything is snug in the intake tract. Also make sure the MAF sensor is installed in the correct orientation and is sealing properly to the intake pipe. Hope some of this info might help!

Thanks,
Alex Goodwin
AlexG@motionlabtuning.com

good info guys!

thought i'd add my 2 cents as well.....i did have a similar experience....no cel's and turning the car off and then back on would usually clear it. For me, it turned out that there was a "fix" for the tune related to the maf's. I'm sorry i don't have the details on the fix, but i believe you can get info from Uprev about it.

I have this issue every so often as well.

I know you can shut off the cel but it must being triggering a cel for a reason.

Sent from my SPH-D710 using Tapatalk 2

Yes, it is triggered for a reason. You are adding FI to your NA car. The two MAP/BARO sensors are very low range sensors and are designed to work off a very small voltage range. Adding boost will exceed that threshold and therefore it is inevitable for this code to get triggered since the boost makes the sensor go out of range. The only fix is to disable the code. The car will no longer go into limp mode once the code is disabled and there is no downside to disabling it.

Sam

Sounds like you need a better tuner. Take it to a reputable shop like Jotech or one of many others in our area. They should be able to help you out.

Jotech installed his SC and probably tuned it.:inoutroflpuke:

So then why is he asking for our opinions on how to fix it? Take it back to them! Has he changed something since they installed it and tuned it? If not, they should be willing/able to fix the problem.

(Oh and me and him met the other day at Jotech!) :-)

I had the MAP code also, Just have my tuner fix it, Exactly what Alex said, Should be a easy fix tho, Took my tuner 5 mins and a few pulls on the street to change it. :)

First, this thread was opened for information regarding how my car was performing. My intent was not to draw negative attention to anyone, especially any specific vendor or tuner.



As always, GTM and Sam are a great source of information. After adding FI, it is not like you can waltz into the dealer and get help. Sam sold me my kit over a year ago and still supports the product today. Those are good traits for a long term vendor IMO.

Alex, this is great information and I appreciated your tips. They were very helpful. FYI, I am on the factory MAF sensors and everything else checked out ok.

I have been going to Jotech since 1995. I have seen Kenny grow his business through at least 3 different locations. Kenny and his crew have always been great to me. They solved the problem today at no charge. Again, these are traits of a great long term relationship with a good shop and tuner.

Thanks for the responses. Perhaps this thread will help someone else in the future on a custom tune.

So what did the shop do? Was it disable the code or something else. I just got my car out of the shop and it keeps going into limp mode if I get on the gas.

are you getting the limp mode with CEL's or limp mode without?