Toyota RAV4 Forums banner
1 - 20 of 20 Posts

·
Registered
Joined
·
8 Posts
Discussion Starter · #1 ·
Hey guys so back in November of last year I managed to buy the cleanest 200k mile Pennsylvania owned 2005 rav4 from a junkyard I used to work at. there was virually no rust other than some surface spots here and there. The car ran like a champ with no major issues. Well come to around june the car started to have a bit of a hard starting issue where there was times (now majority) the car would take forever to start unless you blipped the gas a couple of times. I thought this to be the fuel strainer to be finally plugged up or a leaky injector and didn't think too much of it.
Then finally one day 10 minutes into my journey to work my fuel tank dipped below 3/4 and boom CEL with the p0442 code. So far the things I've replaced was the purge valve by the airbox and the gas cap with a genuine Toyota cap. 2-3 months now have gone by and this pesky code still shows up as soon as my car gets to 3/4 tank and 10 minutes of driving and now its starting to smell like fuel as soon as the car starts. ( from exhaust and partial engine bay). The car also seems to run worse when that light is on.

So far here is the thing I've done and checked:
Gas cap mating surfaced cleaned
purge valve
smoke test with homemade smoke machine.
Filler neck is damn near spotless other than some surface rust under that little foam section.
I didnt see any smoke coming from the over fill check valve
lines coming to and from charcoal canister look ok.

Guys any help is appreciated. This is driving me nuts
 

·
Registered
2010 2.0 VVTi RAV 4
Joined
·
1,933 Posts
Po442 is a small EVAP leak as you say, caused by

Missing or loose fuel cap
Incorrect fuel filler cap used
Fuel filler cap remains open or fails to close
Foreign matter caught in fuel filler cap
EVAP canister or fuel tank leaks
EVAP system hose leaking
Fuel tank leaking

You appear to have sorted the first one with the OEM filler cap and cleaned the neck.

If the canister etc looks good and you can not find a leak from the smoke, it could be one of the EVAP lines from the purge solenoid (at the engine area) - It is sometimes difficult to see the smoke that end (especially as you say you can smell fuel). Could be the solenoid too

Just my thoughts BTW
 

·
Registered
Joined
·
8 Posts
Discussion Starter · #3 ·
Po442 is a small EVAP leak as you say, caused by

Missing or loose fuel cap
Incorrect fuel filler cap used
Fuel filler cap remains open or fails to close
Foreign matter caught in fuel filler cap
EVAP canister or fuel tank leaks
EVAP system hose leaking
Fuel tank leaking

You appear to have sorted the first one with the OEM filler cap and cleaned the neck.

If the canister etc looks good and you can not find a leak from the smoke, it could be one of the EVAP lines from the purge solenoid (at the engine area) - It is sometimes difficult to see the smoke that end (especially as you say you can smell fuel). Could be the solenoid too

Just my thoughts BTW
Yeah ill hook my machine up to a new spot and test. Funny you mention that because the purge solenoid lines are pretty much the only lines that dont have some form of crack on the end. What are the possibilities that the tank pressure sensor went goofy and started throwing false codes, since one of the symptoms of that going bad is rich startup?
 

·
Registered
Car: red, with some black trim
Joined
·
351 Posts
I've just replaced a fuel filler neck on a completely different Toyota model for the same reason, fortunately there are many different brands of aftermarket necks to choose from and they are cheap to buy so check around before ordering. Toyota dealer wanted 6x more than the online parts supplier. The cheap part fitted just fine.
 

·
Registered
Joined
·
8 Posts
Discussion Starter · #7 ·
I've just replaced a fuel filler neck on a completely different Toyota model for the same reason, fortunately there are many different brands of aftermarket necks to choose from and they are cheap to buy so check around before ordering. Toyota dealer wanted 6x more than the online parts supplier. The cheap part fitted just fine.
Knock on wood. I’m happy if it’s that. Means I don’t have to buy a charcoal canister. Still gotta figure out where the gas smell is coming from on start up. Think it might be a leaking injector now
 

·
Registered
Joined
·
8 Posts
Discussion Starter · #8 · (Edited)
Knock on wood. I’m happy if it’s that. Means I don’t have to buy a charcoal canister. Still gotta figure out where the gas smell is coming from on start up. Think it might be a leaking injector now
Welp after finally replacing the filler neck it's back along with a possible p0455. I'm going to run another smoke test and see if that fancy new paint on the filler neck is messing with the seal of the gas cap.
Still came up immediately after getting to 3/4 tank
 

·
Registered
Joined
·
95 Posts
I am also having a P0442 code. Mechanic did the smoke test and said filler pipe was rotted. Changed it out AND new gas cap and code still returned. I redid a homemade smoke test and the cap was leaking. I just redid the gasket and bought a new cap. Testing the gasket first before replacing the cap which is also new with another new cap.
 

·
Registered
Joined
·
95 Posts
With the gas caps, were they OEM replacements? Aftermarket stuff can throw codes almost from day 1 as the seals are rubbish
I’m not 100% sure but my guess is that the filler pipe and cap were not Original Toyota OEM but aftermarket parts. Hoping the new gasket will work before trying a different new gas cap from Discount Auto (Carquest on the box)
 

·
Registered
Joined
·
95 Posts
Thanks, at this point just tying 1 thing at a time. New gasket and 200 miles later, light is still on. If it did correct the leak, would the check engine light go off on its own? Or do I need to clear it? I would try a new gas cap next.
 

·
Registered
Joined
·
8 Posts
Discussion Starter · #15 · (Edited)
Update. Ran another smoke test with key on and key off. Only clear signs i see are smoke coming out of that little vent hole with the plastic collar on the filler neck. I followed that hose and the metal lines have surface rust but nothing serious. I also smoke tested the old filler neck and there was no leaks now. Symtoms that still show: p0442, OBD discovery says its either testing for or pending p0455, Ocassional hard start after sitting for more than a few minutes and <an hour. Fuel milage could be better but that could be a slew of different things. The frequent fuel smell has lessened after changing injector seals it now usually comes with the hard start or maybe once a week. The check engine light triggers immediately as soon as the condtions for the test meet. This is usually as soon at the fuel tank gets around to 75%. Isn't the car supposed to be off for the test to commence?

Might possibly dry checking the vacuum switching valve on the charcoal canister (anyone got a part #?) But what are they sure fire symptoms and test methods for the FTP? Both of these are cheaper than a charcoal box.
 

·
Registered
Joined
·
8 Posts
Discussion Starter · #16 ·
Update 9/26/22 #2:
ok I took the charcoal box out of the car. Everything looked solid in fact the hoses were not brittle and were surprisingly clean aside from the one little connector hose that runs to that outside vent thing on the filler neck.
The Aisin vsv worked when I put the 9v battery to it and air went through no problem.
For added measure I did spray some carb cleaner into it to make sure it was cleaned then dried with an air compressor.
I LIGHTLY blew out the ports and pulled one of the valves off the box (one with that little rubber vent drain thing and blew through it it had want looked to be a little spider web in it) and then put the thing back together and reinstalled.
Ran a smoke test with my homemade machine and didn't notice any smoke out of the assembly.
filled the car till it just got above 3/4 tank and went for a 30 minute-hour drive. No codes yet but the car did not want to trigger the test read on torque despite going below 3/4 after the drive.

Will update tomorrow
 

·
Registered
Joined
·
95 Posts
Is there a difference doing the smoke test with the key on or off?
Motor vehicle Hood Product Automotive design Automotive tire

This little black box which I assume is a valve has a ticking sound while at idle. Almost like the valve is opening an closing 2-3x per second. Is that normal?
 

·
Registered
Joined
·
8 Posts
Discussion Starter · #18 ·
Is there a difference doing the smoke test with the key on or off?
This little black box which I assume is a valve has a ticking sound while at idle. Almost like the valve is opening an closing 2-3x per second. Is that normal?
Its the surge tank. Not 100% sure what it does either.

But the key on key off deal from my experience doesn't really make a difference.
 

·
Registered
Joined
·
95 Posts
Update. 200 miles since last Check Engine light reset AND new Gas cap gasket, the light came back on. Check the code again and still showing P0442. I cleared the code again and put on the new gas cap I just bought from DiscountAuto. Immediately I noticed a better fit and not as lose as the other “new” aftermarket gas cap. Will keep you posted.
 
1 - 20 of 20 Posts
Top