2013 SHO - A Few Issues

[Rohdox]

Hello everyone, I searched around the forum and didn't really find much that would help...but if I missed something please let me know.

2013 SHO, Non-PP, bone stock.

CEL for "Gas Cap Loose/Off" (And "Check Fuel Fill Inlet" on dash)

• Checked DTCs using ForScan, at first it was a P0456, then eventually started saying Gross leak detected
• Cleared CEL, came back on after about two weeks of driving around
• I have cleaned the fuel inlet, I disconnected the power and the circled side of the evap purge valve and there was no suction at the valve with engine running.

Spoiler: purge valve picture

• Not entirely sure what else to check, car runs fine and doesn't have trouble starting.

A/C on drivers side is warmer than the passenger side by ~20 degrees or so. Car has dual climate control.

• I am suspecting a blend door failure on the drivers side.
• Running the EATC self check did not help.
• There is no clicking/popping noise coming from the actuators.
• I unplugged the drivers side blend door and for some reason the drivers side got colder and the passenger side got warmer.
• Heat is about the same on both sides.

Thanks in advance for any solutions!

 

[Johnbigdog]

With the check gas cap warning, the pcm is detecting a VERY LARGE evap leak. I would send you to the rear of the car to make sure the vent valve can hold a vacuum in the system in addition to confirming the fuel tank pressure sensor is working properly. Making sure it reads atmospheric pressure with the system open.

There could be a few things going on with your A/C system. You could have a blend door system fault or a refrigerant system fault. With how the evaporator core is set up, if there is a low refrigerant charge, the system will not be able to cool the entire evaporator so one side will blow warm, the other cool.

If you pop out the blend door motor and manually move the door feeling no binding, suspecting the door itself is moving through it's full range of travel and not leaking air internally, something may be up with the refrigerant system.

You can try recalibrating the blend doors by removing fuse 46 in the Body Control Module (bcm) [fuse box in the car] waiting one minuet or longer, then reinstall the fuse and turn the ignition on then waiting 1 minuet before operating the climate control system.

 

[luigisho]

 

[Rohdox]

Thanks for your replies,

I did a little more testing on the EVAP issue in ForScan and something seems off.


EVAP Purge valve duty cycle is at 73% at idle, tank pressure is 0.

 

[Johnbigdog]

The purge valve is pulling air through the evap system and the vent is open. I wouldn't say that the pressure being 0 is bad if the vent valve isn't commanded close.

 

[Rohdox]

Another update:

with the vent commanded closed, and purge valve commanded at full duty cycle tank pressure remains 0.

Looks like it might be time for a smoke machine.

 

[Johnbigdog]

Another update:

with the vent commanded closed, and purge valve commanded at full duty cycle tank pressure remains 0.

Looks like it might be time for a smoke machine.

I would volt drop your vent valve and do a visual inspection of the valve. The hole you are looking for is equivalently of something being disconected, a hole chewedtcut into the system or the vent valve not closing. The vent valve not closing could be a power or ground issue so if you command it closed and there is a circuit fault, the valve may not close, but the pcm may still not set a DTC

 

[Rohdox]

I would volt drop your vent valve and do a visual inspection of the valve. The hole you are looking for is equivalently of something being disconected, a hole chewedtcut into the system or the vent valve not closing. The vent valve not closing could be a power or ground issue so if you command it closed and there is a circuit fault, the valve may not close, but the pcm may still not set a DTC

I think I may have found my problem.



That is the line coming off the filler neck. according to the emissions vacuum diagram;


It should be connected to the canister and FTP sensor. Looking at pictures of a new filler neck on rock auto, that tube is definitely supposed to be longer.

 

[Johnbigdog]

If you look at the top of your filler neck where you insert the pump nozzle into the cables filler there is a grated portion that when the tank spits back it falls into a tube and out that drain.

That apears to be that drain and is ok as it's not part of the sealed evap system. A new part may be longer I dont know.

Still doesnt mean your filler neck isn't sealing properly or there is a large leak eslewhere.

 

[Rohdox]

The EVAP issue ended up being a bad purge solenoid. It was stuck mechanically closed. Replaced it today and tank holds pressure without issue.

As for the A/C I need to get a set of manifold gauges.