How many miles should I drive after clearing a CEL...

"Full of the sound of the Gran Fury, signifying nothing." (granfury)
01/08/2019 at 10:41 • Filed to: None

...before getting the safety inspection? I occasionally get a P0442 code (small evap leak), and it popped up yesterday, a day before I go in for a safety/emissions retest (failed because of brake wear, since rectified).

Hopefully its’s just the gas cap. If so, is there anything that can be done to make a better seal? Ages ago I thought I heard/read something about petroleum jelly on the seal to rejuvenate it and seal better.

DISCUSSION (13)

Future next gen S2000 owner > Full of the sound of the Gran Fury, signifying nothing.
01/08/2019 at 10:53

New gas caps are like 10 bucks, maybe just replace it?

jimz > Full of the sound of the Gran Fury, signifying nothing.
01/08/2019 at 11:00

I’m not sure there’s a hard and fast rule. I know CELs/codes disappear after a certain number of ignition cycles if the fault doesn’t recur, but I think it’s only a full drive cycle or two for monitors to report ready after you clear DTCs. I know when I cleared them on my Ranger the monitors all read green by the time I got from home to work.

OPPOsaurus WRX > Full of the sound of the Gran Fury, signifying nothing.
01/08/2019 at 11:01

haha my b ro ther-in-law has been batt ling P0442 for years. He first bought a cheap autozone gas cap, didn’t work. Then he bought a real Touyta gas cap, idn;t work. He replaced the charcoal canister (depending on vehicle either real easy or for him huge pain in the ass. That worked for about a year and then the cheapo RockAuto canister started leaking from every corner.

Demon-Xanth knows how to operate a street. > Full of the sound of the Gran Fury, signifying nothing.
01/08/2019 at 12:13

Three driving cycles. Meaning, warm up, run, cool down.

facw > Full of the sound of the Gran Fury, signifying nothing.
01/08/2019 at 12:21

When I got one of these I just bought a new cap. Probably could have just bought a new gasket thing, but wasn’t much more to get a new OEM cap.

As to resetting it, on mine I just cleared it, but I don’t know how long it takes for things to get back in the ready state.

Spamfeller Loves Nazi Clicks > Demon-Xanth knows how to operate a street.
01/08/2019 at 12:29

This is only applicable to Mopars. Mopar has a fixed cycle which was documented in the past. 3 running cycles minimum 10 minutes must reach 25MPH for a minimum 5 minutes each cycle.

Law allows the manufacturer to define their own cycle for closed loop entry. Honda’s is flexible, so, depends entirely on the specific car.

jminer > Full of the sound of the Gran Fury, signifying nothing.
01/08/2019 at 13:14

If you’ve got a Bluetooth adapter and torque it will pull the emissions status states or ready or not. My last car needed a cat and the shop told me to drive 100 miles to clear the code after I replaced it before retest and get everything back in ready state. I didn’t replace the cat, traded in the car instead :)

Full of the sound of the Gran Fury, signifying nothing. > jminer
01/08/2019 at 13:19

I’ve got a Wi-Fi adapter (iOS) and DashCommand, although I have been running a cheap Autool X50 lately for checking and resetting. Maybe I should pull out my old Android phone and give Torque a try.

Full of the sound of the Gran Fury, signifying nothing. > Future next gen S2000 owner
01/08/2019 at 13:21

Mazda didn’t have one in stock and it was $38. Bought one at NAPA but it didn’t fit. I’m going to try the petroleum jelly trick and see if that has any effect.

Demon-Xanth knows how to operate a street. > Spamfeller Loves Nazi Clicks
01/08/2019 at 13:44

*checks his family car history, tons of mopars with a scattering of other cars with most GMs having carburetors*

...your reasoning explains why my sample set gave that result.

I like cars: Jim Spanfeller is one ugly motherfucker > Full of the sound of the Gran Fury, signifying nothing.
01/08/2019 at 13:47

Hard to give a 100% accurate answer, but for my Golf I reset the light and drove like 50ish miles, then got the e-check done, then about 200 miles after the reset the light came back on but I had passed e-check so it was fine.

Spamfeller Loves Nazi Clicks > Demon-Xanth knows how to operate a street.
01/08/2019 at 13:50

Ayup. Plus I read all the technical docs I could get my hands on. So I knew (and somehow retained) the exact procedure for getting the PCM back into ready closed-loop state after O2 replacement.

Had a lot of very happy customers because I could tell them straight up “you just need to run 2 errands at least 10-15 minutes away, and you’ll be good to go for emissions.”

ivnic8 > Full of the sound of the Gran Fury, signifying nothing.
01/09/2019 at 11:03

In North Carolina, if you are inspected, and the ready states are not set , you can drive for 200 miles. If at that time, the states are not set again, you will get a pass (as long as there are no other issues).

So, in theory, you can reset the CEL, get inspected, not pass due to ready state, drive for 200 miles (one trip will not cause the ready states to reset - you typically need a couple drive cycles ), go back for the inspection, and pass.