SES Light....Suggestions

[bloxmagic]

So today i was on my way home and my SES light came on for no apparent reason. So i pulled over just to check and make sure everything was OK. Anyone have any ideas on what it could be... the light is on solid, i just did a tune up about 3 weeks ago and everything has been fine, it is a 2000 GP GT and it has about 48,000 miles on it and just did an oil change at 46,000.... any help you be greatly appreciated. My take might be the 02 sensor is going bad but then i have 19mpg so i am not sure....

[chad27]

go to auto zone for a free scan

[bloxmagic]

oh alright thanks did not know about that well i will post up what they tell me

[TDCRacing]

Yep post it up. We will be glad to help. There are 1000's of codes. So it would be kind of hard to guess.

[bloxmagic]

so i went to autozone and got the code and then i wrote it down then lost it somehow but the code was talking about how the coolant temp was not the same as the thermostat temp so i bought a new temp sensor and am going to install it... if anyone has any other ideas let me know

[chad27]

well that could have been it. just wait to see if it comes back on.

[bloxmagic]

ok now i got the code P0128 coolant temp below thermostat regulating temp... so i replaced the thermostat and how do i reset the ses light?

[chad27]

you will need the scan tool they will reset it sometimes at auto zone just depends tell them you replaced the part

[MizzBecca]

dont be suprised if it comes on again, on my 94 it comes on if i go over 60 then slow down n press the break. nothing comes up on the scan, but mine is like 15 years old lol

[bloxmagic]

yea i replaced the thermostat but now i had trouble replacing the ECT sensor and was not able to do it.... does anyone have any suggestions on how this should be done? Thanks!

[dstout]

You can disconnect the battery and let it sit for a while and it should clear the code.

[bloxmagic]

well i cleared the code thanks for the help only time will tell if i get the code back.. thanks again!!!

[chad27]

battery never worked for me

[dstout]

how did you clear the code?

[bloxmagic]

well i un did the ecm fuse and un plugged the battery terminals then i let it sit for a while and either that did it or i fixed the problem and the code just went away i have no idea

[dstout]

Good job just keep watching it, it may or may not return.

[bloxmagic]

alright yea thanks for the info!

[Swash]

I noticed in your sig that you have a 180* t-stat, if you don't have the PCM tuned for it - you will continue to get P0128 codes (depending on weather - especially when colder). Just FYI.

[TDCRacing]

IT's weird. I've heard of this happening. Only heard. Never got to meet anyone it actually happend to. But I ran a 160 for about a year. Through summer and winter and this never happend to me.


If it's saying the thermostat was a different temp the inside gauge then it's a bad thermostat. But in realits there is no way the PCM even know's what temp the gauge is at inside. It operates off of the Sensor it self

[bloxmagic]

yea it was a weird code i could not figure it out but i just went ahead and replaced the thermostat and reset the code and its been fine