EVO 3 "Check Engine" Light

[FuGZ]

I was wondering if anyone had any similar symptoms/problems with their 63s, i'm facing a problem i've been tackling for about a year already.

Vehicle: Putra
Engine: 4G63 EVO III
Problem: "Check Engine" light appears then car becomes

1. Underpowered
2. Exhaust temp reading higher than usual
3. Rather not smooth acceleration

Now, from number 2, i was guessing, if that's the case, there'd be prob with the fueling. I'm running with Walbro and the fuel pressure reading is fine. Couldn't be anything wrong with the fuel delivery unless whatever happens in the combustion area goes wrong.

It seems this problem tends to get worse; from rarely (last year) with the "check engine" light on, occasionally, sometimes and now, always (today). When it was on "sometimes", i changed the knock sensor since the diagonse machine indicated it was knock sensor prob, but didn't quite help. Engine could be knocking, but it's not knocking, in fact it had gone thru a top overhaul just about a month ago.

Googled up some answers, could be the O2 sensor, since the reading is wrong, fueling at the last mile could be incorrect, hence the exhaust temp. Tried to give the O2 sensor a shot, but we couldn't screw it out, and stopped before we actually broke something.

Will be leaving the car with my mech to do more tests like running the car without the knock sensor connected.


So i'm curious, has anyone experienced such thing before? Could it be dirty injectors and a dirty fuel filter which could be casuing such? Enlighten me pls experts and experienced ones.

Or any idea on an easier way (maybe there's a trick) to take out the O2 sensor?

 

[xinghonh]

happen once to me on my 4g93
they use sum kinda equipment to detect
and detected that my o2 sensor is faulty

 

[clanzkiller]

nvr encounter it before...does it something to do wit your ecu ?or wiring?

 

[raja_emeperor]

check your airflow bro, seriously check the airflow b4 you suspect 02.

 

[BananaBoyz]

air flow...power tr...o2 sensor & knock sensor

 

[jinkl]

too many factors bro
only way is to use a logger to findout

knock sensor problems will cause ur ecu to retard ur timing causing lost of power too , as for o2 sensor, o2 sensor only functions when u r cruizing or idling, other than that, it doesnt affect the tuning

 

[FuGZ]

that's right jin, too many till headaches, too many IFs. but what kind of logger are you talking about? the common machine used to diagnose with?

thing i read on the o2 sensor when i googled is, if the o2 sensor if farked, knock sensor tends to go crazy too, hence the check engine. but i'm not too sure how true that finding is, not sure if it will really trigger the knock sensor to go haywire.

clanz, i don't know to be honest. but i doubt so, would be the least suspected thing i guess.

Bnnboyz, guess those are the things to be checked 1 by 1, sorting out which one to check first is a headache.

raja, will do.

xing, if that's the case which i hope, i wish there was an easier way to take that o2 sensor out. manifold's got old rust like an oldie, stock e3 ma.

will take all advice into testing soon. it's sad driving an e3 having it so underpowered. thanks for the replies tho.

 

[arrowhead]

not contributing, just dropping by to say hi.. so... HI

 

[catan]

Try to check the knock sensor wire go into the ECU.... it might be came out or loose conncetion ...
last time my frend GTI also happen like this ....the check light came out but still can runing smooth .... after found the wire came out and fixed it ... now the car running more smooth .... and check engine light gone .....
can try i out ....

 

[huakenny]

go workshop ask them diagnose...since got CEL, sure got error codes

 

[BLaCkHoWLiNG]

Go DJ Accesories, remove the bulb.. everything fine wan...


*cabut*

 

[evo555]

my evo hav o2 sensor light on...how?