CHECK ENGINE LIGHT

[FirstJeep]

So today on my way in to work the engine light came on and at the same time the temp gauge dropped to cold, it was up to just about half way then went right over to the "c". I got out had a look and everything looked good, except the upper rad hose felt like it was full of nothing. After i turned the jeep off and then on the gauge went back to nurmal but the engine light stayed on.
Any ideas? My dealer said i could bring it in but dont expect to get it looked at right away, nice.

 

[valvestem]

So today on my way in to work the engine light came on and at the same time the temp gauge dropped to cold, it was up to just about half way then went right over to the "c". I got out had a look and everything looked good, except the upper rad hose felt like it was full of nothing. After i turned the jeep off and then on the gauge went back to nurmal but the engine light stayed on.
Any ideas? My dealer said i could bring it in but dont expect to get it looked at right away, nice.

Sounds like the thermostat might be sticking, or the coolant temperature sensor is/was malfunctioning. Did you have "heat" the whole time, or did the engine seem overheated, cold or normal temperature?

 

[BluPhant]

Dont know specifically about your symptoms, but u can pull codes from the jeep without a code reader. Check out this thread for some info.

 

[Jeger]

Dont know specifically about your symptoms, but u can pull codes from the jeep without a code reader. Check out this thread for some info.

I dont think that works on an 06 At least not on my CRD

 

[FirstJeep]

I had heat while i was driving, then the gauge went down and i just turned it off, i didnt notice if it got cold. I was thinking about unplugging the battry for a few hours and then if the light comes back on later on my way home i guess in for warranty it goes tomorrow.

 

[indieaz]

As mentioned above - sounds like thermostat was stuck open (if it was stuck closed you would have seen the temp guage rising). Thermostats are super cheap and easy to replace - you may wan tto just try swapping it out first before wasting any time at the dealer.

 

[FirstJeep]

indieaz -- why would the thermostat be pooched already you think? But i agree it is most likely that. I am going to pick one up on my way home and swao it out and disconnect the battery and hope it resets the light. I just hate seeing that light on, nothing worse to ruin your friday right.
Do you think the fact that they use that red antifreeze instead of the normal green stuff has anything to do with this? Because i had a chev blazer before with the red stuff and it seemed like i had to change the thermostat every year.
I also tried to get the codes but it appears that it does not work.

thanks for all the input guys, it is really nice to be able to talk to people that know about this stuff, rather than call the dealer who gives you the old " just bring it in and we will get to it when we can" line.

 

[2003KJ]

There's no telling why it just took a dump at such an early age. I'd just call it a fluke for now.

As far as swapping it out, i'd be a afraid of voiding my warranty in any way by replacing parts on my engine if I were you. However, as mentioned, tstats are very easy and pretty cheap. I've never done one on the 3.7 (yet), but I know on other vehicles, they don't come with the gasket, so be sure to order one while your there (they average about 20-30 CENTS...dirt cheap).

For the red/orange vs. green coolant, the red is actually better. It cools better, and doesn't break down near as quick as the green stuff does. It is also not recommended that you mix the two.

 

[BluPhant]

Just as an fyi, you can get a basic OBDII code reader on ebay for around $50.00, maybe even less. Invaluable tool, and works for any US vehicle from 96 onwards.

-Blu

 

[FirstJeep]

Thanks for all the advice everyone. Yesterday i disconnected the battery for a few hours and then at the end of my work day i reconnected it, the light is off and has not come back on. I did about two hours of driving since then and it all seems good. I,m goona think it was just something to do with the cold weather up here.

 

[2003KJ]

Just as an fyi, you can get a basic OBDII code reader on ebay for around $50.00, maybe even less. Invaluable tool, and works for any US vehicle from 96 onwards.

-Blu

They also work on imports...again anything 96 or newer.

 

[indieaz]

indieaz -- why would the thermostat be pooched already you think? But i agree it is most likely that. I am going to pick one up on my way home and swao it out and disconnect the battery and hope it resets the light. I just hate seeing that light on, nothing worse to ruin your friday right.
Do you think the fact that they use that red antifreeze instead of the normal green stuff has anything to do with this? Because i had a chev blazer before with the red stuff and it seemed like i had to change the thermostat every year.

The type of coolant isn't related. They just fail - really it's a crapshoot. Thermostats are just liek that...it's not like they wear out...they just randomly fail.

As for voiding your warranty mentioned above - that's a good point. I wonder how they could prove you swapped the thermostat though? I've not had a thermostat come without a gasket before...but i've mostly worked on GM vehicles.

OBD2 scan tool is definitely a handy thing to have.

 

[2003KJ]

I've not had a thermostat come without a gasket before...but i've mostly worked on GM vehicles.

Done a tstat on a XJ 4.0 and a Dakota 2.5, neither had gaskets included....pretty stupid if you ask me.

 

[thecause17]

I've not had a thermostat come without a gasket before...but i've mostly worked on GM vehicles.

Done a tstat on a XJ 4.0 and a Dakota 2.5, neither had gaskets included....pretty stupid if you ask me.

A lot of that depends on where you buy it....if you go to advance or a place like that, they sometimes don't include a gasket, or the gasket os a seperate part...if you go to the dealer, they come together a lot of the time. I ran into this with my Ranger I had before my Jeep. Went to advance, they had the thermostat, but not the gasket (o-ring), and they didn't even carry it. I went to the dealer and bought them together, as one part.

 

[2003KJ]

I've not had a thermostat come without a gasket before...but i've mostly worked on GM vehicles.

Done a tstat on a XJ 4.0 and a Dakota 2.5, neither had gaskets included....pretty stupid if you ask me.

A lot of that depends on where you buy it....if you go to advance or a place like that, they sometimes don't include a gasket, or the gasket os a seperate part...if you go to the dealer, they come together a lot of the time. I ran into this with my Ranger I had before my Jeep. Went to advance, they had the thermostat, but not the gasket (o-ring), and they didn't even carry it. I went to the dealer and bought them together, as one part.

True. I never understood why you wouldn't sell it with the thermostat to begin with. Why some places decide to sell it separate is beyond me... :-k

 

[theshoestore]

Posted here because I just had a similar thing happen today.

Started the Jeep up, and the block heater was plugged in. The needle was already about 1/2 of the way up to normal operating temp. Drove about 2 miles and got on the freeway, and noticed the gauge had dropped all the way back to C. The check engine light also came on. I checked the heater and it was hot, so I know the Jeep didn't suddenly have a massive cooldown. I exited and restarted the Jeep, gauge was right where it should be at normal temp.

Called the dealer, and they didn't seem to concerned, and to call back if it started again.

Did you ever get it looked at or have the issue again?

 

[JeepJeepster]

If the heat if working fine then it appears like its just a sensor fluke or a problem with the guage. Strange it happened on two 06's though.

 

[2003KJ]

Might be a coolant temp sensor issue. Bring it to Autozone and have them pull the code before the light goes off.

 

[Ry' N Jen]

indieaz --
Do you think the fact that they use that red antifreeze instead of the normal green stuff has anything to do with this?

Never heard of red antifreeze before!
When we had our water pump replaced and the coolant flushed at the dealership they replaced it with green coolant.

 

[JeepJeepster]

Never heard of red antifreeze before!
When we had our water pump replaced and the coolant flushed at the dealership they replaced it with green coolant.

ouch. unless they flushed the system thats not good.

http://www.lostkjs.com/forum/phpBB2...ays=0&postorder=asc&highlight=coolant&start=0

you would think a dealer would know what to use. Guess Im giving them to much credit.