2012 nismo 370z won’t start after gascap change

Datnismo3323 · 03-02-2018, 06:15 PM

So recently I’ve been having an issue with the “loose gas cap” message. Got tired of it and replaced the cap, got one from autozone to see if maybe that made it go away. Sure enough my temperamental little bag of horses decided not to start. So with some gas added I get her up and running keep in mind it now will not start without pressing the gas. No codes, old cap works fine car starts. New cap, car runs in limp mode and won’t go past 3500. I’m beyond how that can affect anything but I’m not very savvy about gas caps and what they can cause to go wrong. Any advice would be nice before I pay the luxurious 160 dollar diag fee. In my opinion is sounds like a faulty sensor, maybe crank shaft, mass air or canister purge valve?

SouthArk370Z · 03-02-2018, 07:16 PM

I'd try another new cap.

Buzzkill247 · 03-02-2018, 09:09 PM

1) possibly a generic gas cap that is creating vaccum. Try a replacement OEM cap (these usually should be replaced every 45-50k anyway due to erosion and lack of seal forming)
2) fuel pump has worn itself out due to having to work harder with no tank pressure from failed cap
3) bad MAP (? spitballin here)

The key for me is it will start with pedal depressed, and won't trigger past 3500. That triggers a few red flags in an unusual combination.

It is possible that the combination of poor fuel pressure reg caused the MAF to become off calibration in relation to ECU. You could (just to rule out a few factors) reset the ECU in the 3 step process of resetting ECU op, idle, and throttle setpoints

Quicksilvers · 03-02-2018, 11:05 PM

I recommend using a Nissan OEM replacement gas cap. Other than a bad gas cap sounds like a failed fuel pump if your 370Z will not start.

Spooler · 03-03-2018, 12:15 AM

Quote:

Originally Posted by Quicksilvers

I recommend using a Nissan OEM replacement gas cap. Other than a bad gas cap sounds like a failed fuel pump if your 370Z will not start.

Or a broken pump assembly top hat.

03-02-2018, 06:15 PM	#1 (permalink)
Datnismo3323 Base Member Join Date: May 2017 Location: VA Posts: 12 Drives: 2012 Nismo 370z Rep Power: 7	2012 nismo 370z won’t start after gascap change So recently I’ve been having an issue with the “loose gas cap” message. Got tired of it and replaced the cap, got one from autozone to see if maybe that made it go away. Sure enough my temperamental little bag of horses decided not to start. So with some gas added I get her up and running keep in mind it now will not start without pressing the gas. No codes, old cap works fine car starts. New cap, car runs in limp mode and won’t go past 3500. I’m beyond how that can affect anything but I’m not very savvy about gas caps and what they can cause to go wrong. Any advice would be nice before I pay the luxurious 160 dollar diag fee. In my opinion is sounds like a faulty sensor, maybe crank shaft, mass air or canister purge valve?

03-02-2018, 07:16 PM	#2 (permalink)
SouthArk370Z Premium Member Join Date: Nov 2010 Location: South Arkansas Posts: 8,435 Drives: 2014 Challenger Rep Power: 324197	I'd try another new cap. __________________ Steering Lock Links - Search The370Z Bookmarklet - FSM @ NICOclub Mankind has progressed past the need for war but we haven't evolved that far. - NachoMahma

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Car won’t start	Zthirty4NISMO	Nismo 370Z	9	08-03-2016 06:35 PM
[FOR SALE] 370z Nismo Part Out GTR Start button dome lenses etc	waffle riot	Parts for sale (Private Classifieds)	13	10-23-2015 08:10 PM
2012 Z won't start	Don	Engine & Drivetrain	5	05-18-2014 01:40 AM
RED start button for 2012!	scottIN	Nissan 370Z Pricing / Ordering Discussions	12	11-23-2011 02:12 AM

03-02-2018, 09:09 PM	#3 (permalink)
Buzzkill247 Base Member Join Date: Jan 2018 Location: FL Age: 49 Posts: 91 Drives: 16 370z KAD GunM 7AT Rep Power: 663	1) possibly a generic gas cap that is creating vaccum. Try a replacement OEM cap (these usually should be replaced every 45-50k anyway due to erosion and lack of seal forming) 2) fuel pump has worn itself out due to having to work harder with no tank pressure from failed cap 3) bad MAP (? spitballin here) The key for me is it will start with pedal depressed, and won't trigger past 3500. That triggers a few red flags in an unusual combination. It is possible that the combination of poor fuel pressure reg caused the MAF to become off calibration in relation to ECU. You could (just to rule out a few factors) reset the ECU in the 3 step process of resetting ECU op, idle, and throttle setpoints

03-02-2018, 11:05 PM	#4 (permalink)
Quicksilvers A True Z Fanatic Join Date: May 2017 Location: Atlanta, GA Posts: 2,039 Drives: 2017 370z Rep Power: 25462	I recommend using a Nissan OEM replacement gas cap. Other than a bad gas cap sounds like a failed fuel pump if your 370Z will not start.