I think my thermostat is stuck open?

synviper · Post by **synviper** » Tue Feb 16, 2010 9:13 pm

Okay I drive my car daily and it used to show the coolant temp raising to close to 200 and dropping Like usual.

But as it has gotten cold outside that gauge has now not moved. Like i drove 7 hours and the needle stayed buried at zero.

would the thermostat be the issue or what thanks.

Oh and its on a 03 srt4 if that makes any difference.

TheRandom1 · Post by **TheRandom1** » Tue Feb 16, 2010 9:14 pm

Thermostat, gauge, wires, fuse. Rest of your gauges working properly?

synviper · Post by **synviper** » Tue Feb 16, 2010 9:17 pm

um... it seems that my gas gauge has been falling alot faster like 67 miles to a tank and im half full

and i drive pretty granny like in the snow.

but i have these cels too. Idk if these might something to do with it?

p0071 is ambient temp sensor performance

p0517 is battery temp sensor high

TheRandom1 · Post by **TheRandom1** » Tue Feb 16, 2010 9:19 pm

Interesting.

synviper · Post by **synviper** » Tue Feb 16, 2010 9:21 pm

... Well im heading out to go get something im just going to reset the ecu and see if maybe shit works again.

TheRandom1 · Post by **TheRandom1** » Tue Feb 16, 2010 9:22 pm

Couldn't hurt. Sounds like there's an actual error tho. Have you done anything under the hood lately?

synviper · Post by **synviper** » Tue Feb 16, 2010 9:24 pm

MS install which i didnt undo the negative terminal on the battery.

Which could have pissed off the computer :/

TheRandom1 · Post by **TheRandom1** » Tue Feb 16, 2010 9:26 pm

That's possible.

If your temp sensor isn't operating properly, that would explain your fuel mileage drop. Perhaps it's actually bad, but I don't know how to test it, other than putting a new one on and seeing if it works.

(That answer came from LSP not me, I wasn't sure if it would make a difference or not)

Post by **occasional demons** » Tue Feb 16, 2010 9:29 pm

Increased fuel consumption would be a good sign... A better way would be to simply put your hand on the upper hose. If it starts warming up a minute after starting, (dead cold) then the t'stat is open. The hose should stay cold for a good while just idling. Then it should heat up rapidly once the t'stat opens.

The battery, and ambient temp sensor may be one and the same. Some years use separate sensors some don't. Check the sensor in the air inlet/or charge tube, IIRC on SRT's.

thisdieingdream1 · Post by **thisdieingdream1** » Thu Sep 23, 2010 4:11 pm

hey i just got a cold air intake adn the air temp sensor dont really fit in the hole its really lose so i taped it in there adn all
but is there a way that i could just get rid of it and not use it?

g_force58 · Post by **g_force58** » Thu Sep 23, 2010 7:16 pm

I had the same problem with my cai. I fixed it by getting a pcv grommet for a small block chevy V-8 valve cover. Installed it in the cai, put the sensor in and things have been fine for about 5000 miles. Mine was not and is not loose n never fell out or anything.

Post by **occasional demons** » Thu Sep 23, 2010 7:55 pm

My AIT sensor has been lying on the inner fender for some time now. As long as it is plugged in, it is happy.

OB · Post by OB » Thu Sep 23, 2010 10:14 pm

The ambeint temp sensor and intake air temp sensor are two different things. The first one sits down near the lower radiator support and measures outside air, hence the term "ambient". The other is in the intake and is used as part of the calculation for AF ratio and fuel trim. If you leave the IAT sensor out of a CAI, it will send warmer temps to the PCM, thus resulting in poor performance due to lack of fuel enrichment. However, since the IAT readings don't weigh heavily in the PCM's fuel calculations (in terms of priority), the difference in power is probably minimal.

Had to clear that up

P.S. IIRC, not all PL models came with the ambient temp sensor. I'll have to check if mine has it one of these days. Only reason I know it exists for sure is because it's in the FSM.

sidepipe87 · Post by **sidepipe87** » Thu Sep 23, 2010 10:57 pm

thisdieingdream1 wrote:hey i just got a cold air intake adn the air temp sensor dont really fit in the hole its really lose so i taped it in there adn all
but is there a way that i could just get rid of it and not use it?

wtf does this have to do with jake's thread???

synviper · Post by **synviper** » Thu Sep 23, 2010 11:40 pm

Lmao, its all good. Hopefully he got the information he needed.

thisdieingdream1:

If you go to advanced/pepboys/autozone/napa, most of them sell a grommet kit that you could buy, i had to get one, i wish i could remember the ID of the grommet but i cant remember off the top of my head. Sorry.

FAC3L3SS · Post by **FAC3L3SS** » Fri Sep 24, 2010 8:44 am

I was wondering that shit myself Ryan, but no one cared so I thought it was normal. They just started answering.

Post by **occasional demons** » Fri Sep 24, 2010 9:37 am

synviper wrote:
but i have these cels too. Idk if these might something to do with it?

p0071 is ambient temp sensor performance

p0517 is battery temp sensor high

I would have said something, but it was mentioned, FWIW.

I figured he would have been thrashed for dredging up an old thread.

Relevancy must be the new thing now, eh?

Post by **occasional demons** » Fri Sep 24, 2010 9:39 am

OB wrote:The ambeint temp sensor and intake air temp sensor are two different things.

Not on pre NGC. They are one and the same. Also controls charging rate on 2002-older.

04R/T · Post by **04R/T** » Sat Oct 09, 2010 1:12 am

Bringing this back from dead...

I have seen this happen on a Stratus and a Breeze with the 2.0 engines. It seems the original Chrysler installed thermostats would have the cage that retains the spring break, this would release the spring holding the thermostats valve closed. The car will run cold all the time.

All though the thermostats failed, its a much better failure than having it stuck closed.

Post by **occasional demons** » Sat Oct 09, 2010 1:19 am

It would need to be a very old t'stat to fail closed. most if not all are now "fail safe", as in they are supposed to fail in the open position.

But I don't think the cage breaking was part of that plan.