Too lean

wolfcyn · 07-19-2016, 07:34 PM

so i was at my local parking garage with a few buddies last week. as we were getting ready to leave, i noticed my check engine light came on. so being my cautious self, i took it to auto zone and got the free check up thing. turns out my car is running too lean in cylinder back 1 and 2. only mods i have on the car is a stillen gen 3 long tube intake, and a muffler delete. car has about 13,000 miles on it. any advice?

another thing is my RPM during idle changed from 500ish to 1000ish so when i come to a complete stop, my car will jolt forward which isnt the most comfortable feeling
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jrb55gh · 07-19-2016, 07:46 PM

I understand from many posts on this forum that the Gen 3's lean the mixture. That is the reason they increase performance when installed by themselves. That with the muffler delete may lean it beyond what the ecu views as normal. Thus your lean code for both banks. A tune would fix probably the problem.

Just curious what the more experienced experts on the forum will say.

SOUTHZZ · 07-19-2016, 08:43 PM

Need a tune.
With those mods,car is running too lean

DEpointfive0 · 07-19-2016, 08:54 PM

Did you disconnect the negative terminal during install?
Are your MAFs clean?

wolfcyn · 07-19-2016, 10:25 PM

Quote:

Originally Posted by DEpointfive0

Did you disconnect the negative terminal during install?
Are your MAFs clean?

yes i disconnected the negative terminal of the battery during the install. not sure about the MAF sensor. not sure how they would get dirty. ill clean them off and see if that helps

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SouthArk370Z · 07-20-2016, 08:02 AM

The rule-of-thumb is:
If you change only intake side OR only exhaust side, you don't need a tune.
If you change both intake side AND exhaust side, you need a tune.

MAFs probably aren't the problem but they are very easy to R&R. One of the first things to look at when engine is running rough.

DEpointfive0 · 07-20-2016, 02:04 PM

Quote:

Originally Posted by wolfcyn

yes i disconnected the negative terminal of the battery during the install. not sure about the MAF sensor. not sure how they would get dirty. ill clean them off and see if that helps

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Disconnect the negative terminal again, and when you plug it back, drive a bit not crazy to let the computer relearn

wolfcyn · 07-29-2016, 06:09 PM

update!! disconnected my battery and a few day later, i guess my ecu became familiar with it and my engine light went off

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xdragus · 08-07-2016, 07:52 PM

Hi piggy backing on this thread. Would I need a tune if I got the stillen g3 intake and Fast intentions HFC non resonated?

seymore4 · 08-07-2016, 08:01 PM

Quote:

Originally Posted by xdragus

Hi piggy backing on this thread. Would I need a tune if I got the stillen g3 intake and Fast intentions HFC non resonated?

It would be a good idea

SouthArk370Z · 08-07-2016, 08:15 PM

Quote:

Originally Posted by xdragus

Hi piggy backing on this thread. Would I need a tune if I got the stillen g3 intake and Fast intentions HFC non resonated?

Intake mods only - no tune needed.
Exhaust mods only - no tune needed.
Intake + exhaust mods - tune needed.

Wheels3309 · 08-07-2016, 08:55 PM

Quote:

Originally Posted by SouthArk370Z

Intake mods only - no tune needed.
Exhaust mods only - no tune needed.
Intake + exhaust mods - tune needed.

This makes sense to me

07-19-2016, 07:34 PM	#1 (permalink)
wolfcyn Base Member Join Date: Dec 2015 Location: Mississippi Posts: 67 Drives: 2016 Nissan 370z 7AT Rep Power: 9	Too lean so i was at my local parking garage with a few buddies last week. as we were getting ready to leave, i noticed my check engine light came on. so being my cautious self, i took it to auto zone and got the free check up thing. turns out my car is running too lean in cylinder back 1 and 2. only mods i have on the car is a stillen gen 3 long tube intake, and a muffler delete. car has about 13,000 miles on it. any advice? another thing is my RPM during idle changed from 500ish to 1000ish so when i come to a complete stop, my car will jolt forward which isnt the most comfortable feeling Sent from my iPhone using Tapatalk Last edited by wolfcyn; 07-19-2016 at 07:50 PM.

07-19-2016, 07:46 PM	#2 (permalink)
jrb55gh Base Member Join Date: Mar 2013 Location: DFW Texas Posts: 149 Drives: '13 370z black 7AT Rep Power: 12	I understand from many posts on this forum that the Gen 3's lean the mixture. That is the reason they increase performance when installed by themselves. That with the muffler delete may lean it beyond what the ecu views as normal. Thus your lean code for both banks. A tune would fix probably the problem. Just curious what the more experienced experts on the forum will say. __________________ Ecutek \| DIY HR350 upper plenum \| DIY ported lower manifold \| TurboXS cbe \| FI rhfc

07-19-2016, 08:54 PM	#4 (permalink)
DEpointfive0 Premium Member Bitches Join Date: Jan 2012 Location: SoCal Posts: 14,824 Drives: a lot Rep Power: 17151	Did you disconnect the negative terminal during install? Are your MAFs clean? onzedge likes this. __________________ Do YOU want to know what/where I got my username from? ( Click to show/hide ) NSFW due to language:

07-20-2016, 08:02 AM	#6 (permalink)
SouthArk370Z Premium Member Join Date: Nov 2010 Location: South Arkansas Posts: 8,435 Drives: 2014 Challenger Rep Power: 324198	The rule-of-thumb is: If you change only intake side OR only exhaust side, you don't need a tune. If you change both intake side AND exhaust side, you need a tune. MAFs probably aren't the problem but they are very easy to R&R. One of the first things to look at when engine is running rough. __________________ Steering Lock Links - Search The370Z Bookmarklet - FSM @ NICOclub Mankind has progressed past the need for war but we haven't evolved that far. - NachoMahma

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07-19-2016, 08:43 PM	#3 (permalink)
SOUTHZZ Enthusiast Member Join Date: Jan 2014 Location: ALABAMA Posts: 305 Drives: 09 NISSAN 370Z CS M6 Rep Power: 3400	Need a tune. With those mods,car is running too lean

07-29-2016, 06:09 PM	#8 (permalink)
wolfcyn Base Member Join Date: Dec 2015 Location: Mississippi Posts: 67 Drives: 2016 Nissan 370z 7AT Rep Power: 9	update!! disconnected my battery and a few day later, i guess my ecu became familiar with it and my engine light went off Sent from my iPhone using Tapatalk

08-07-2016, 07:52 PM	#9 (permalink)
xdragus Base Member Join Date: Aug 2015 Location: toronto Posts: 47 Drives: '17 PW Nismo Rep Power: 10	Hi piggy backing on this thread. Would I need a tune if I got the stillen g3 intake and Fast intentions HFC non resonated?