cherokeelaredo'90

So for the longest time I've been thinking I need a tranny cooler or a larger one than the factory one.. because my jeep usually runs just below the 210 mark, but when I come to a stop for a long period ot seems to like to heat up to above 210 until I start moving again. I have a guess that it could be from my low idle issue, which I'm ordering a new tps and iac valve to hopefully solve that issue, but what else could it be from???
Tonight I was going down a dirt road in 4hi full time because it was pretty slick. Just cruisen at above 2000 rpm and moving at around 20ish mph. I glance down and realise my temp is up near the tick just before the red section...! That's not good. And then eventually I turn around and start heading down the road just idling now because it's downhill and I look down and the temp is now down below 210 instantly... what's up here!?! Help would be nice. Thank you in advance. Oh and it's not the fan clutch or the waterpump I just replaced those over the summer

Bbasso

my first reaction is the fan clutch...
Just not moving enough air over the cooling system.

Bustedback

Replace the fan clutch and make sure the electric fan is coming on. Don't waist your money on a new TPS or IAC, those will not fix an overheating at low speeds condition. When was the last time any cooling system maintence was done? I think it's time to do some.

cherokeelaredo'90

I went through the whole cooling system this summer. New fan clutch, water pump, thermostat, installed an inline tee for a radiator cap, ran flush through it a ton of times, also ran water through it a couple times. I tried to do everything to it!
And I believe it is a low idle problem because when I first start it it seems to run at 700 rpm idling and then after running like 15 minutes at temp the idle seems to drop to below or around the first tick mark. If I rev the engine up to around 700 to 1000 the jeep begins to cool down. That's why I thought it was a faulty tps and iac because once they get hot they fail from what I've read. I'm a little lost

cherokeelaredo'90

Oh and the efan does kick on but it seems like it goes on between 210 and the tick before the red. I've been meaning to wire It to a switch to turn it on before but I haven't got around to it

rand4x4

I havw a 95 and have 210 as an avarge, I put a tranny cooler and it didn't do munch.
But it is good to keep your tranny fluid cooler. Go not buy to big of one or it will block to much of your Rad, my temp gauge goes up and down all the time but never over heated to the fact of pooring out somewhere.

cruiser54

It could be as simple as a sticking thermostat. I only use the factory ones anymore. 83501426 at the dealer. Nice stable temps summer and winter.

What have you done so far to address the idling issue?

djb383

So, everything has been replaced but the radiator? Hummm.

cruiser54

I thought of that, too. But seeing the swing in temps, and the number of poor replacement thermostats out there, It might be worth a shot.

djb383

......and it seems like the efan should be on well before "the tick before the red". Wonder if the efan "on" is correct but the gauge is giving a wacked reading as to when it turns on?

cruiser54

218* for the e-fan.

djb383

Yep, way before "the tick before the red mark".

cherokeelaredo'90

Yeah I guess I'll go down to the dealer and pick up a new thermostat. It wouldn't hurt.
The radiator is factory and when I bought it 2 years ago I had it boiled out. I should've bought a new one but whatever.
I was looking at a bunch of hayden's stacked coolers and they have an 11x5 7/8, then a 11x7 1/2 and a 11x9 1/2. I was thinking bigger is better but maybe I'll just get the 11x7 1/2 one.
As far as fixing the low idle I have done your(cruiser's) ground refresh. I have checked a bunch of sensors according to the lunghd website. All the sensors seemed alright except for the manifold temperature one. It was reading a little bit higher ohms than what it should be. I cleaned it up pretty good but I haven't checked it again..
Thanks for all the replys guys!

cruiser54

Remove the MAT and clean the tip of it by spraying it thoroughly with throttle body cleaner.

cruiser54

Check this out.