Allpar Forums banner

1 - 20 of 34 Posts

·
Registered
Joined
·
171 Posts
Discussion Starter #1
I've gotten this code twice in a month, both times it seems to happen when the tank gets down to half.

Thinking of buying a new gas cap just to see if that helps, if not have to dig deeper.

Any other ideas?
 

·
Premium Member
Joined
·
20,074 Posts
You can also check the hoses to make sure there aren't leaks there.
 

·
Registered
Joined
·
1,043 Posts
Try cleaning the O-ring on the gas cap, then apply a small amount of O-ring grease to it, it can help seal. Q-tips work great for the cleaning and applying the grease.

You can get the O-ring grease at any hardware store in the plumbing department.
 
  • Like
Reactions: paullybob

·
Super Moderator
Joined
·
31,983 Posts
My wife's 2012 Chrysler 200 has had an intermittent code P0441 almost since new. Sometimes with a check engine light, sometimes not. It is not the gas cap. She was tapped at 5-10 mph around 7K miles, so I'm thinking that disrupted something. Or it was the fuel pump replacement they did around that time, when the gauge would intermittently plunge to empty.
 

·
Super Moderator
Joined
·
21,362 Posts
Some older evaporative system rubber hoses have dry-rot issues and begin cracking, especially at the ends where they mate to a fitting or nipple.
I have seen poor sealing between the filler tube pipe end and where the gas cap seals against it. Metal openings can get a layer of rust on them and plastic openings can get bumped and nicked with the pump nozzle. Sometimes light sanding and a smear of grease around the filler tube opening will seal a small leak.

At the shop, we use a smoke machine to fill the tank and vapor lines with a low-pressure vegetable oil based smoke with a florescent (black light) dye added. After a couple of minutes of smoke fill with the car on a lift, we can usually find the leak source.

A small evaporative leak (P0456) can be from a 0.010" (0.25mm) pinhole.
 

·
Registered
Joined
·
4,633 Posts
. . . I've gotten this code twice in a month, both times it seems to happen when the tank gets down to half. Thinking of buying a new gas cap just to see if that helps, if not have to dig deeper. Any other ideas? . . .
Fuel tank level must be below about 85% full before any leak detection processes are invoked. Before firing the "parts cannon" and replacing the fuel filler cap, try this test. Remove the filler cap. Securely tape a small, thick vinyl sandwich bag over the filler tube opening and seal it completely. Erase the diagnostic code. Drive the vehicle for a few days. Does the code return? If NO then you isolated the problem to a poor seal with the fuel cap. If YES, then the problem is NOT the seal at the fuel filler cap and lies elsewhere.

What is the model year and engine in your PT Cruiser?
 

·
Super Moderator
Joined
·
21,362 Posts
I believe that this is the 2007 2.4L N/A. The fuel tank must also be above 1/4 tank to run the OBDII tests (including evap integrity).
You were having a fueling issue with filler nozzle click-off and spit-back before. Was this ever resolved?
This could be related to the ORVR/EVAP issue you are having now. Something may be blocked. See TSB # 14-001-09A:
http://www.xkjeeps.com/TSB/tsb_xk_1400109a.pdf
 

·
Registered
Joined
·
171 Posts
Discussion Starter #8
You are correct, it's 2007 touring edition and often burps gas on fill-up even on slowest setting.

That has not been resolved yet.

Recently bought a Milwaukee camera scope tool to see what type of pistons are in my 396 engine in the old Chevy truck.

Maybe I can use it to try to see hoses near gas tank.
 

·
Registered
Joined
·
2,978 Posts
My 04 PT was giving the same code, also at a half tank. I changed the gas cap and it never occurred again.
 

·
Registered
Joined
·
171 Posts
Discussion Starter #10
I bought a new locking gas cap after some kids shot my rear window and windshield on my 1965 C10 truck, went in neighbors driveway behind his camper trailer and sliced his spare tire, probably destroyed other people's stuff too I have not heard about.

Anyways still getting code.

I've watched several videos and since the car has 170,000 miles, thinking of replacing the purge valve.

Was going to buy or build a smoke tester, but on some of the videos it says if a valve does not close all the way, you would not find it with a smoke test.

Found one on eBay for $24.66 and free shipping, AutoZone is almost $60.00.

I probably overpaid at O'Reilly, the locking gas cap was $19.00 but I was there buying spark plugs for the old truck and just bought it because I was already there.
 

·
Registered
Joined
·
4,633 Posts
. . . I've watched several videos and since the car has 170,000 miles, thinking of replacing the purge valve. . . .
Are you getting code P0456, small evaporative leak?

The purge valve on the evaporative system is used for the intrusive leak test for large and medium leaks. The test for small leaks is passive / non-intrusive and does not use the purge valve.

After engine shut down there is a natural cooling effect on the liquid in the fuel tank. As it cools it creates a slight vacuum and a control valve in the ESIM (evaporative system integrity monitor) closes the system to outside air. As the vacuum increases a switch in the ESIM will close and stay closed for a period of time. If the switch does not remain closed for a specified period of time then a small evaporative leak is noted.

The hose between the ESIM device at the vapor canister and filter must be free and unobstructed to allow 2 way air flow. Check filter and hose for plugging. See attached image.

ESIM schematic components 3.gif
 

·
Registered
Joined
·
171 Posts
Discussion Starter #12
Yes it's the small leak.

To check this, does one need to lower the fuel tank?

Was looking in Haynes manual.
 

·
Registered
Joined
·
4,633 Posts
. . . To check this, does one need to lower the fuel tank? . . .
You do not lower the fuel tank to check the vapor canister and its filter. I made an assumption that a 2007 PT Cruiser would use ESIM for vapor emission control. But it is possible that it could have an older system called NVLD (natural vacuum leak detection). Find the vapor canister under the car and near the fuel tank. See attached image that shows ESIM and NVLD. ESIM has 2 hoses attached and the ESIM device. NVLD vapor canister has 3 nipples with hoses attached. Which do you have?

Vapor Canister ESIM NVLD.gif
 

·
Registered
Joined
·
171 Posts
Discussion Starter #15
Saw on emissions sticker under hood this car has natural vacuum leak detection, last night while replacing tensioner and pulley.

Will check hoses next time have a day off.
 

·
Registered
Joined
·
4,633 Posts
. . . . Saw on emissions sticker under hood this car has natural vacuum leak detection, last night while replacing tensioner and pulley. . . . . .
Attached is schematic relevant to NVLD emissions system. This replaces schematic in post #13, Oct 26.

NVLD Emissions Diagram 3.gif
 

·
Registered
Joined
·
171 Posts
Discussion Starter #17
I have the car up on ramps under rear wheels, seems on passenger side I have found where the hoses are at.

I'm going to have to try to remove something to try to get access to that hose.

Looking in Haynes manual for PT Cruiser, it appears the filter is bolted down to the top of the tank.

However that might be the other style, the manual is vague.

It gives instructions on removing natural vacuum leak detector, no pictures.

Going to try removing whatever is in the way to gain access to hose.
 

·
Registered
Joined
·
1,043 Posts
I have the car up on ramps under rear wheels, seems on passenger side I have found where the hoses are at.

I'm going to have to try to remove something to try to get access to that hose.

Looking in Haynes manual for PT Cruiser, it appears the filter is bolted down to the top of the tank.

However that might be the other style, the manual is vague.

It gives instructions on removing natural vacuum leak detector, no pictures.

Going to try removing whatever is in the way to gain access to hose.
I sent you a PM with a link to download a copy of the Gen2 service manual from my Google Drive, it should help with your troubleshooting. ;)

Page 14-29 is for the Fuel Tank

Page 9-301 is the electrical troubleshooting for the P0456 error code.
 

·
Registered
Joined
·
171 Posts
Discussion Starter #20
I got the pictures in wrong sequence, removed bolt, and finally got to use my new battery ratchet, was kinda fun!

I moved that part out of way as much as possible to reach my hand up and feel the hose headed towards driver's side, it's not going anywhere, probably going to that filter and filter is bolted to top of tank.

My plan is to drive car until it's almost empty, then put on ramps, use my transmission jack to lower tank enough or all the way to gain access to those hoses, etc.

Called a repair shop, when I was younger would never consider doing that, told them about my issues, they said $115.00 for diagnostic including smoke test, I never mentioned smoke test just gave what code says and tried new gas cap.

Have a feeling $115.00 might not tell them anything, no smoke leaking, then they will call back asking about doing advanced diagnosis for more $ and then give very expensive repair options.

Nope, will lower tank another day and go from there.

It is kind of interesting to see what it would cost for diagnostic, that $115.00 is about what I paid for battery powered ratchet on sale at harbor freight.
 
1 - 20 of 34 Posts
Top