CEL Flashing @ 170km/h

gilly02le · Post by **gilly02le** » Fri Apr 20, 2007 11:57 am

Ok, so last night i though hell why not.. took the car out on the highway and attempted to push it to the 190km region... so i'm at about 170, and 4500 rpm, and the check engine light comes on and starts flashing, so i too the next exit off the highway and pulled the codes.. to my surprise, No Codes...? At first i thought it was a misfire code because i have a UDP on a 2002, and normally when if i floor it and let it rev all the way to 6krpm, the check engine light will sometimes come on and tell me there is a misfire..(happening around 5500rpm) but it will go right back off in a few minutes.. do you think my car just thought it was misfiring and thats why the CEL was flashing.. ?? i just think its odd because it only detects a misfire at 5500rpm.. not as low as 4000-4800rpm...And I've also never seen it flash.. only come on.. all i know is.. when i hit 170, the money light started flashing....got me a lil worried..

boxcarfan · Post by **boxcarfan** » Fri Apr 20, 2007 5:58 pm

i know the MIL will flash if the computer thinks the cat is going to be damaged within mins.

-and another thing is that there is 2 sides to the pcm...the genric side of codes and the man. specific side. make sure you check both.....the genric side is for emmisons related only stuff

gilly02le · Post by **gilly02le** » Sat Apr 21, 2007 12:41 am

hmm, wonder if its because i am fooling my lower o2 sensor by having it a few inches out of the stream, instead of in the cat..
either way.. it tripped me out, and i slowed right down because i wanted to see what the hell was up.. the other wierd thing is that thier was no check engine light on pervious to it flashing... and it went away after i backed off the trottle a bit..

boxcarfan · Post by **boxcarfan** » Mon Apr 23, 2007 1:50 pm

yea it probly thinks the cat is getting way too many HCs in it, and HCs will kill your cat faster than anything
(HC=Hydrocarbons...big word for gas lol)

weber · Post by **weber** » Mon Apr 23, 2007 2:05 pm

I willing to bet its your UDP.

Thats what my car would do at high RPM's.. it'd just flash it a few times and wouldn't stay there.

But times have changed, CEL is always there anyway lol. Screw it.

gilly02le · Post by **gilly02le** » Mon Apr 23, 2007 2:51 pm

im thinking your right about the CEL being caused by the o2 sensor mod.. because i just did that mod like 2 weeks ago.. and never before has it flashed the CEL when at high speed like that.. only if im over 5KRpm..(because of the UDP) which i was not.. was only at about 38-42Krpm when it started to happen..

AgentV3 · Post by **AgentV3** » Mon Apr 23, 2007 3:36 pm

It probably is related to your UDP, since a flashing CEL usually indicates a potentially dangerous engine condition, and a high speed misfire can tear it apart.

gilly02le · Post by **gilly02le** » Tue Apr 24, 2007 11:19 am

i don't think so... since i've had the UDP for six months.. and i never had any issues with high speed and the CEL flashing.. And two weeks ago when i did my o2 sensor mod.. now im starting to see it happen..