TJ running hotter than usual

[Chris 11]

My jeep is a 2004 4.0 auto. I have owned it for a year so far.
Since day one, once warmed up, temperature gauge will read at around 195-200 and wont fluctuate AT ALL whatever the situation ( heat, cold, AC on, traffic…)

Last week I replaced TPS and upstream O2 sensors (Mopar) and added grille inserts from DV8 to protect radiator from debris.

Since then, whenever im driving uphill for a long while or sitting in traffic specially on a hot day with the AC on, temperature will go all the way up to around 225 but never reach the red zone ( maybe because I didnt dare to drive it long enough for it to fully overheat)

Im wondering if new O2 sensor or TPS has anything to do with that or is it the grille inserts that are restricting airflow? Or is it just a coincidence and something else in the cooling system is happening?

Or is this just something normal on a TJ

PS: changed water pump and thermostat cover a year ago when purchased.

 

[Duck Doctor]

Grill inserts are likely reducing airflow.

 

[Jerry Bransford]

X2, my guess is those grill inserts are restricting air flow enough to make the engine run a little hotter.

And that it only ran at 195-200 before the grill inserts were installed tells me someone installed the wrong thermostat with a likely 180 degree rating. The engine should run closer or right at 210 which happens when the correct 195 degree thermostat is installed. Install a conventional thermostat, avoid so-called "fail-safe" thermostats that are known to fail too easily in the open position which stops them from working. And make no mistake, the engine is operating more efficiently at temperatures like 210 where they were designed to run at and what the PCM was programmed around.

 

[lBasket]

Another product to solve a problem that never existed in the first place

 

[JHammett]

I had those for a minute (liked the look), started overheating a bit in 110 F degree weather, pulled over to the side of the road and popped them off with a knife and no more overheating ever again.

Sold them for a few bucks on FB the next day.

I recommend doing the same.

*I am also a member of a few Jeep clubs on Facebook to join on runs every so often. Every time we have monsoons out here (AZ), like clock-work there are several posts in the groups from people who say, "I went out mudding after the rains and now am running much higher temps/ my CEL came on for high temps. What do I do?" The post the day before was their entire Jeep caked in mud....hmmm coincidence?

 

[Chris 11]

X2, my guess is those grill inserts are restricting air flow enough to make the engine run a little hotter.

And that it only ran at 195-200 before the grill inserts were installed tells me someone installed the wrong thermostat with a likely 180 degree rating. The engine should run closer or right at 210 which happens when the correct 195 degree thermostat is installed. Install a conventional thermostat, avoid so-called "fail-safe" thermostats that are known to fail too easily in the open position which stops them from working. And make no mistake, the engine is operating more efficiently at temperatures like 210 where they were designed to run at and what the PCM was programmed around.

Thank you for your input Jerry.
Will get rid of the inserts right away. And start looking for a new thermostat.

Problem is Mopar parts are super hard to come by where i live, would any store brand 195 thermostat work? Or should I just ship one from the US?

 

[Chris 11]

I had those for a minute (liked the look), started overheating a bit in 110 F degree weather, pulled over to the side of the road and popped them off with a knife and no more overheating ever again.

Sold them for a few bucks on FB the next day.

I recommend doing the same.

*I am also a member of a few Jeep clubs on Facebook to join on runs every so often. Every time we have monsoons out here (AZ), like clock-work there are several posts in the groups from people who say, "I went out mudding after the rains and now am running much higher temps/ my CEL came on for high temps. What do I do?" The post the day before was their entire Jeep caked in mud....hmmm coincidence?

Same here, was mostly attracted by the look since they are the most era apropriate for the TJ compared to the newer honeycomb look.

Relieved to hear you had the same experience with it, wasn’t looking forward to change the radiator or worse having the head gasket starting to act up.