service engine soon

white04alero · 02-23-2010, 12:46 AM

hey yall my SES light came on the other day. went to autozone, they said it was an EVAP emissions leak (small leak). they said it's prob my gas cap. replaced it. light is still on. do i need to reset it or will it go off if the problem goes away? if it hasnt gone away because it's not fixed, what all could it be? if it hasnt gone away because the light needs reset, how do i reset it? the guy up there said to get on the highway and go up to 60 mph, slow down, hit 60 again, slow down, hit 60 again, and then slow down, and it should shut off. i think he's FOS, so help me out here yall.

[ion] C2 · 02-23-2010, 12:54 AM

There's certain times when the diagnostic trouble code system will run the test to see if a certain part of the car is working right. Like he said, usually EVAP operation occurs under deceleration at a certain speed.

It will go off by itself after a certain number of successful cycles of proper operation, but you can have the code cleared if you want, and then see if it comes back. If it's not vapor leaking from the fuel cap, it's going to be something else along the line of the EVAP system, such as the EVAP purge solenoid/canister, or the EVAP hose itself.

Chris2000 · 02-23-2010, 01:48 AM

This might sound ridiculous but I think there is something to do with the gas right now. My dad and I both threw a code with our SES light. It smelled like gas comin out of the exhaust and was a little rough driving. We both erased the codes off of each car and filled up at Shell for gas and light hasn't come on since. Maybe too much ethanol + winter additives? Just a theory so don't flame.

jayson_waltz · 02-23-2010, 01:54 AM

Naw it's not the actual gas there, it was just coincidence that they both came on at the same time. It was either the gas cap or some random little thing. Prob just shut off from the gas cap now, it takes a certain number of engine run cycles for it to shut the light off.

white04alero · 02-24-2010, 12:24 AM

Quote:

Originally Posted by [ion] C2

There's certain times when the diagnostic trouble code system will run the test to see if a certain part of the car is working right. Like he said, usually EVAP operation occurs under deceleration at a certain speed.

It will go off by itself after a certain number of successful cycles of proper operation, but you can have the code cleared if you want, and then see if it comes back. If it's not vapor leaking from the fuel cap, it's going to be something else along the line of the EVAP system, such as the EVAP purge solenoid/canister, or the EVAP hose itself.

i see. so where is the evap canister/ hose? lol. when i work on stuff, i do it to my 32 year old truck, so help me out if you dont mind. or if there's a picture you could link me to?

Cashdollar2009 · 02-24-2010, 12:37 AM

Lost my gascap somehow a month ago. The ses light came on. I replaced the cap, 100ish miles later it went out. I think i read either read it in the haynes manual or somewhere else that the computer takes around 100 miles or so after the cap is replaced for it to read the seal again. Sorry if my "terminology" is incorrect. Regardless, 100 miles after my gas cap replacement, the light went back out.

[ion] C2 · 02-24-2010, 01:20 AM

Quote:

Originally Posted by white04alero

i see. so where is the evap canister/ hose? lol. when i work on stuff, i do it to my 32 year old truck, so help me out if you dont mind. or if there's a picture you could link me to?

On the 2.4L, it's chillin down near the A/C compressor.