I had this problem before.

[demarpaint]

Let me first state I am trying to avoid going back to the dealership. I will go as a last resort.

CEL came on a while back in my 08 Jeep, it was the code for evap emissions system/gas cap. I checked the gas cap, and cleared the codes and it ran great for about 2+ months.

Last night I used the remote start, the Jeep started and stalled, CEL came on again. Looking back at my notes the same thing happened last time, remote start, stall CEL comes on. A disconnect of the battery clears the CEL.
Any ideas? I will try and pull codes again, the only code I have come up with is for the gas cap/evap system.

PLEASE NOTE CODE PULLED BY AAP, THEY WON'T CLEAR CODES. I DIDN'T CLEAR THE CODE WITH THE SCANNER, I DISCONNECTED THE NEG BATTERY TERMINAL. SHOULD I TRY CLEARING THE CODE WITH THE SCANNER (I can borrow one now). THAT'S IF I HAVE THE GAS CAP EVAP EMISSIONS SYSTEM CODE?

Battery was disconnected less than a minute to clear the code, not sure if that matters.

Again trying to avoid the dealership if possible.

As always THANKS!

 

[xxch4osxx]

I have had that PO455 code for evap small leak detected, a few times with my truck and I just clear the code with my handheld scanner.

 

[demarpaint]

I don't have a problem doing that if it is going to be one those minor annoyances. I just don't want to flunk state inspection if the computer logs that a code has been cleared. The dealers around here charge an hours labor to clear the gas cap code, and won't smoke test the evap system until you go back a second time with the same code. Then they'll look further but the money wasted first time the car was brought in is lost.

The fact that the battery was disconnected for less than a minute and cleared it the last time, does that matter? Or is clearing with a scanner is better? This is new tech to me, my next newest vehicle is a 93.

 

[xxch4osxx]

As far as passing your state inspection, I don't really know. Here the emissions test is a machine hooked up to the exhaust pipe and the exhaust is checked for certain levels of gasses. They don't check if the computer has any codes or anything. I think that the engine has to go through a certain number of "cycles" after a code is cleared for it to read green, but I am not 100% sure on that.

 

[ARCOgraphite]

I gotta get a scanner too, Demar - tell me what you find thats good for around 100 bucks. Its not great to clear code by disco the battery - causes undue elec stress and your car will require about ~ 1 week to get all the trims relearned.

 

[JHZR2]

Does NYS do a gas cap pressure test, or test the actual system? In NJ we pressurize the gas cap to verify seals, in DE they actually pressurize the fuel tank system.

Not sure how it is in NYS, but in NJ it is no big deal to bring a car back for re-inspection if it failed.

 

[OilNerd]

Originally Posted By: JHZR2
Does NYS do a gas cap pressure test, or test the actual system? In NJ we pressurize the gas cap to verify seals, in DE they actually pressurize the fuel tank system.


Inside NYC metro area, not sure. Outside the the NYC metro area, no, just a computer hookup -- OBD-II check for '96+. Visual check of gas cap only.

 

[eljefino]

Better to clear the code with a scan tool than to disco the battery. You need most/all of your I/M monitors complete and surgically clearing the code just requires its monitor and any dependencies to run... the cat, misfire etc will have already run and will stay in memory. In short a couple days will do it.

My county requires both a gas cap pressure and OBDII scan despite the redundancy. I have a suspicion many inspection mechanics skip the cap test, a technical violation. The state cannot amend the tiniest aspects of its inspection/clean air plan without filing a big impact report whatsamajigger with the EPA so we're stuck with this nonsense.

 

[Vikas]

How old is your vehicle? For model year 2000 and before, your state allows at least two incomplete on emission test. The evaporator tests can only run if the gas tank between 1/4 and 3/4. You will need a your own (or borrowed for long time) scanner which gives you IM (Inspection Monitor) Readiness details. The cheapest Autel from Amazon (under $40) has that ability.

Before you take your vehicle for inspection, make sure
1) NO currently lighted CEL
2) No more than 2 incomplete IM if (model year 2000 or before)

- Vikas

 

[Vikas]

Originally Posted By: eljefino
Better to clear the code with a scan tool than to disco the battery. You need most/all of your I/M monitors complete and surgically clearing the code just requires its monitor and any dependencies to run... the cat, misfire etc will have already run and will stay in memory. In short a couple days will do it.


Method of erasing codes (using scanner and/or disconnecting battery) does NOT matter.There is NO difference. There is NO way to "surgically clear" the codes as you put it. That would have been nice but that is not how it works.

Once you have "fixed" the problem, you have to go through the "drive cycle" so that the test will re-run and if the problem is really fixed, the test will be completed successfully.

I have unfortunately too much "experience" with this stuff :-(

- Vikas

 

[ATS-V]

If you don't reset the code will it go out on it's own after a few driving cycles?

You could go to AutoZone and get the code read. If you were close I code read the code for you. After you get the code you may be able to better pin point the problem.

 

[mechtech2]

The battery disconnect should clear it.
Some cars do indeed have hidden codes, but this [EVAP]is normally not one of them.

Vacuum lines, bad cap, cap loose , loaded up charcoal canister, bad EVAP valve, wiring, connector are things to check.

 

[demarpaint]

Thanks for the replies, I'll try and answer all questions, and give more info.

08 Jeep Liberty, I realize I can bring it to the dealer, however if it is the gas cap they charge an hours labor, and send you packing, if it happens again they go thru the whole Evap emissions system. I hate the dealership and am trying to avoid them.

Remote start started the Jeep it stalled CEL on, this happened once before only code was P0455. I don't have a scanner, AAP read the codes, and said it was against the law to clear them.

A battery disconnet had everything fine for a few weeks. I would rather not disconnect the battery because of possible harm to the computer and electrical system.

IIRC NYS inspection hooks up a scanner and checks for codes, and a safety check. I have until December before inspection and warranty running out.

I will buy a scanner, I'm tapped out on cash right now.


I thought if something was really wrong the CEL would come on right away, that is not the case here. I also read stories where people had these problems and they were never able to find a fix. I wish I had more faith in the dealership, I don't!

Thanks for the replies.

 

[Scott_Tucker]

Most OBDII vehicles will not clear the codes by simply disconnecting the battery. I don't know about your Jeep. You should clear it with a scanner.

 

[Vikas]

Invest in your own scanner; come up with a budget and find the best one within the budget. If you watch for sales on Amazon or Harbor Frieght, you can pick one up as low as $30.

I have no idea how remote start / stall / P0455 are connected to each other. The P0455 can *NOT* affect the driveability of the engine.

If you take your Jeep to the dealer, I am sure he will reset the light and will ask you to come back if it lights up again. He probably will charge you an hour of labor. The next visit, he will change the gas cap and will ask you to come back again. If the light comes back again, then only he will do any serious diagnosis such as look for real leaks using smoke machine and then he will charge you quite a lot.

Is your car under warranty? If so, he needs to fix it but you will have to put up the fight. If you are sure that you always tighten the gas cap at least 3 clicks, take it to dealer and fight it. Tell them that you already have scanned it and tell them the code and insist that you always tighten the gas cap. If nothing else, you will have a record of this problem. You should not have to pay a dime if you know you did not leave the gas cap open. If it is bad gas cap, it should be covered under warranty. You don't even have to mention anything about remote start and stall triggering P0455. Don't confuse the dealer

As I said before, evap test runs rarely and lot of conditions have to be right before it will run to trip the code. With a better scanner, you can look at the Mode 6 data and then find how closely the test succeeded or failed (but that scanner will cost you $100+)

There are lots of hits on google for "P0455 Jeep".

- Vikas

 

[demarpaint]

Thanks Vikas. The Jeep is under warranty. P0455 is the evap system/gas cap. I know how these guys work quite well. First trip in they'll say gas cap and bang me for an hours labor, second time back they will have to actually trouble shoot it. I will be out that hours labor for the first visit. I pump my own gas and make sure the cap is properly installed.

I realize there is no connection with P0455 and the remote start issue I mentioned. But both times the CEL came on was under the same conditions. Start the engine with the remote start, stall, CEL on. Code p0455.

Note I didn't clear codes with the scanner, the CEL went off by disconnecting the battery. It remained off for about 400 miles the first time and about 250 miles the second time. I was under the impression codes had to be cleared with the scanner. but as I mentioned this is new technology for me. My 93 Ford is much more user friendly.

I will have to get a scanner. I hesitated a few months ago and missed out on a great deal on Ebay. Kicking myself now!

 

[Vikas]

The OEM gas cap is under warranty. When you go and visit the dealer and tell them point blank what you want to be done and that it better be covered under warranty, he will relent. When I take my car to dealer or a shop for emission related problem, I will show them my own scanner and tell them I have the code and I want the repair done under warranty. If they are not going to cover the repair, do not hook up their scanner as I will not pay for them to tell me what I already know.

Once you are aware of their standard operating procedure and you tell them upfront that you will not tolerate it, they will comply. In the end, they do get paid by the manufacturer for the warranty work, albeit not as much if they could get it directly from you but some business is better than no business.

Given that evap tests run under specific conditions, it is likely that the light will stay off for 100s of miles before triggering again. You don't want this to become more frequent after your warranty runs out which it most certainly will. You probably have a real leak somewhere in the system. Couple weekends ago, I was with my mechanic and he had a Taurus for similar problem. He had spent lot of time on trying to find this problem. He got to the purge canister, checked the solenoid, ran Mode 8 evap test from his fancy Snap On scanner (I was helping him to press some buttons on it but eventually he had to hook up the smoke machine and located the pinhole leak on the filler neck. He did NOT replace the filler neck as I suspect the customer probably was not prepared to shell out the money :-( The mechanic had spent at least a whole hour of honest time on it and that alone must had cost some coin to the customer.

Get it fixed under warranty rather than delaying it. You should have already reset it once, tell them that and get them to start diagnosis rather than sending you on the way with another reset.

- Vikas

 

[eljefino]

Originally Posted By: Vikas
Originally Posted By: eljefino
Better to clear the code with a scan tool than to disco the battery. You need most/all of your I/M monitors complete and surgically clearing the code just requires its monitor and any dependencies to run... the cat, misfire etc will have already run and will stay in memory. In short a couple days will do it.


Method of erasing codes (using scanner and/or disconnecting battery) does NOT matter.There is NO difference. There is NO way to "surgically clear" the codes as you put it. That would have been nice but that is not how it works.

Once you have "fixed" the problem, you have to go through the "drive cycle" so that the test will re-run and if the problem is really fixed, the test will be completed successfully.

I have unfortunately too much "experience" with this stuff :-(

- Vikas


allright my poor phrasing. If you follow a drive cycle flow chart you'll see, starting from scratch (battery disco that it first checks for misfires then full temperature etc. The flow chart for my GM puts gas tank pressure somewhere in the middle/end.

If you clear the EVAP leak code, it leaves the misfire diagnostic pass intact, so it can in fact finish the roster of I/M monitors faster.

The 2 incomplete rule is a Cumb cty ME rule, may not be the same in NY.

Interesting factoid, my car only runs the test between 1/4 and 3/4 tank and above a wintery temp.

 

[demarpaint]

Thanks for the info. I gassed up today, made 100% certain the cap was on properly. I came home, disconnected the battery for 15 minutes while eating a quick lunch. If the CEL comes on again, which I'm pretty much expecting I will go back with the Jeep loaded for bear. I will tell them what code I found and inform them of the reset, ruling out the gas cap being improperly installed. Then they can do their thing and know fully that they won't get a dime from me. I wish it didn't have to be this way but a buddy of mine went through something along this order with my dealership and warned me.

Fingers crossed it doesn't trip the CEL again, but once again I'm expecting it. I'm guessing within a few 100 miles the CEL will be glowing in all its glory.

 

[mechtech2]

You won't harm the computer or electrical by disconnecting the battery!
You will lose your clock and radio stations, though.
And your idle and other driving parameters will have to be reset as you drive. This may take a few days.