Chek Engine Light

Started by sideways_styles12 · Aug 31, 2010 · 6postsSMF 2010–26

sideways_styles12Aug 31, 2010, 3:57 am · #1

i need to get my wifes galant smoged but the monitors wont set and the check engine light wont come on. yesterday we drove to san jose and back ant the light came on. i shut the car off and restarted it and the light went out. the monitors were never set and the last code was downstream 02 sensor no activity present, a buddy of mine said to reflash the computer with the scanner and that might help. any advice would really help all i can think of is bad pcm

Phisherman09Aug 31, 2010, 4:05 am · #2

the monitors can still not be ready despite the CEL not on. you have to drive the specified drive cycle for it too reset the monitor. it can take anywhere from 10-100 miles of driving.

if the downstream o2 is inactive, then your cat is probably bad, therefore its not going to reset the monitor due to the inactivity.

i would see what the voltage of the downstream o2 is. if it matches the values of the upstream, than the cat is not working, and should be replaced.

Jsvob03Aug 31, 2010, 11:05 pm · #3

Phisherman09the monitors can still not be ready despite the CEL not on. you have to drive the specified drive cycle for it too reset the monitor. it can take anywhere from 10-100 miles of driving.

if the downstream o2 is inactive, then your cat is probably bad, therefore its not going to reset the monitor due to the inactivity.

i would see what the voltage of the downstream o2 is. if it matches the values of the upstream, than the cat is not working, and should be replaced.

also, make sure the exhaust isnt leaking. even a fairly small leak can cause o2 codes.

MaxpowSep 12, 2010, 7:18 am · #4

hate to resurrect a thread but if you ever just need to pass and aren't worried about a code at the moment just pull your cluster, put e-tape over the engine light area and you're set, light gone.

Jsvob03Sep 14, 2010, 12:10 am · #5

maybe it dfferent in cali, but usually they just plug into the obdII port, and check the state of the monitors, and whether or not there are ANY codes. Hell, if you pull the bulb for the check engine light, you'll fail for that in ohio.

any new news?

MaxpowSep 14, 2010, 1:42 am · #6

Damn, Cali they just visually check if the light is on.. that trick has worked countless times. That sucks for you guys, your smog shops must actually invest in real techs.