JeepRage

iTrader: (1)

i ran the code test, and came up with coolant temp sensor, front 02 sensor, knock sensor. i cleared the codes and reset the light without repairing a thing, and it has not come back on. the light initially came on when i added a fuel injection cleaner... whats the deal, any need to worry, will it come back on if something is really wrong??

Sonic

I wouldn't worry if the car feels as though its acting normally again, and yes it will come back on it there is a problem.

Daniel B. Martin

That annoying Check Engine Light will come back, sooner or later. Probably sooner.

got rice?

iTrader: (2)

how is the car running?

if there's a rough idle or hesitation, it's the coolant temp sensor.

if there's hesitation, it could be the o2 sensor or coolant temp sensor.

if the car feels slower but runs smooth, it's probably the detonation sensor (it retards the ignition timing).

if you have lower gas mileage, it's either/or the temp sensor or o2 sensor.

if you're around 60k miles, replace the o2 sensor anyway. the coolant temp sensor is inexpensive and not difficult to replace.

JeepRage

iTrader: (1)

60K?? hehe thats pathetic... im talking 153,000 and counting!! jk, but yeah, one code is the O2 sensor, it did have slight hesitation, so i used a fuel cleaner, and thats when the light CAME ON. so i reset, and nothing is yet to return, including 0304. perhaps the cleaning junk worked, otherwise i gotta get that fuel box thingy cleaned again for $50 or whatever it is. had to do it around 100K too

DCmax

iTrader: (2)

I had the same thing happen to me. Codes for the 02 sensor and the Knock sensor came up and I reset the ECU and the ML light hasnt come back on since. I made an appointment to get the 02 sensor and various other parts fixed but something came up and I had to cancel. I havent noticed the car acting any different but I will still get it checked out as soon as I have time.