MustangSang

ok so this has been happening for some time now so I'll start from the top...
I have a 2006 v6 just regular nothing fancy other than an after market hood that has quite the scoop on it*... I had an issue where my alternator had gone bad so I took it in to the shop and had that replaced then promptly took it into auto zone and replaced the battery as Tuffy's didn't when they changed the alternator... so a couple days later (this was in December cold as $hit btw) the check engine light popped on and I noticed that the temp gauge was only reading about a quarter of the way where as it usually sits at halfway. But at the time I chalked it off to it being cold and the scoop was bringing in all kinds of cold air and after 100+ mi of driving in a day, that's got to have something to do with it being cold and figured the engine light was coming on for something they messed up in the alternator crap as he told me to bring it in and I got a call bout half hour later and he's on the line telling me that nothing is the matter and it's "normal" which I've continued to think.... but now... now... it's warming up and my car is running to temp however my check engine light is on yet again and it's coming back with the p code that the engine is running cold and it's saying that it's the thermostat or a sensor (I'm not sure what sensor or where any ideas on this would b helpful)...

Anyways, the car seems to run fine, no weird noises or squeaks, I really think that my thermostat is stuck open but the last time I had thermostat problems was with my 98 and she was overheating so I'm really scratching my head on this one, I don't want to replace the thermostat if it isn't bad and I defiantly don't think I want to go messing with sensors I don't even know about...



*see it's quite the scoop (idk if it matters or not)

bl817

I would just make sure you have the right amount of coolant and that your thermostat housing isn't leaking. a known issue with the v6 cars as yours. could just be the gauge reading low when its cold outside. the stepper motors that control the needles are another known problem with the early s197 cars. good luck

Derf00

Use a handheld scanner that plugs into the OBDII Port and reads actual engine data to get a reading of the coolant temp of the temp sensor itself. If that reading doesn't' make sense then that sensor is probably bad.

MustangSang

Well have to try these when the rain stops thanks for the tips guys

cruisin5268d

Definitely check the code, otherwise you are flying in the dark so to speak.

It's petty easy to check the thermostat and its cheap to replace but I wouldn't get too crazy with that until knowing what the code(s) is/are.

Lethaldosage423

The coolant temp sensor is in the thermostat housing! it sounds like a stuck open thermostat to me too. If your going to replace the thermostat, do your self a favor and replace the whole housing and the little coupler hose between that and the water pump. they are renowned for cracking and leaking so while your in there, a little preventative maintenance will go a long way!

they are easy to replace, i remember doing mine on my 05 V6, real simple. Make sure you get all new gaskets too!

MustangSang

Thank you all for your replies the info was very useful, we planned on replacing the thermostat this weekend as it finally stopped raining so I'll do the hose n that too, didn't realize that sensor was right there, thanks again for the info I'll keep u guys updated with the status

MustangSang

Did that before coming here that's how I fig it was the thermostat or sensor, it popped a P0128

MustangSang

Changed the thermostat a few days later the light went out, problem solved, thanks again guys for your tips!

cruisin5268d

Awesome! Now go play