Ok last night with the severe rain here in nj i went out to start my car and it wouldn't start for like 10 secs. It just kept turning over so i turned the key off and tried again and it stated right up without any problems thereafter.When i was driving this morning i seen the check engine light on. I accessed the ecu and it read out 3 codes. Knock sensor,downstream oxygen sensor and temperature sensor. The car was running fine without a hitch, so i decided to reset the ecu and see if the check engine light came on again. It did not! My question is if 1 or all of these were bad i wouldn't they come back. And is it typical for 3 things to go at once or is the ecu spitting out these 3 things because it wouldn't start for 10 seconds and these could be probable causes? I'm confused.

 

sometimes one faulty device can trip another. I believe it maybe a good chance that the KS is tripping the o2 sensor.

when you reset the ECU the light didnt come back on because the ECU after being reset need about +/- 200 miles to analyze the system again so, it will be a little bit but after performing its checks, after it notices devices and sensors arent giving the proper read out they should then it will throw back the codes again.

the Coolant temperature sensor, is very easy to change and should take less than 2 minutes. I would recommend changing that and the KS, and then reset the ECU and see if it throws the codes back again (especially for o2 sensor).

 

Thanx alot for the reply MDeezy, I was thinking the same thing [replace coolant temperature sensor 1st] its only $15.00 and the o2 and KS are $100+ each. This sucks cause i have to replace both front and rear brakes as well, so the brakes get done now and everything else will have to wait for mo money! Maybe i'll get lucky and the codes won't show back up again. .....hey i can always hope

 

The KS code is tripped by the O2 code, not the other way. If you have a bad O2, the code for it will come back possibly with the KS code again. The O2 should be changed first, not the KS. You can check for the KS code shortly after you've replaced the O2.

 

Ok, now i'm confused , but MDeezy said it "may be" and you seem quite positive so i'll go with the o2 1st. Good lookin out!