I am running a 130 t state that automaticly stays in open loop if it ever fails so to not overheat. I know its making me get worse gas mileage, but its only by maybe 10 miles over the course of 300 miles all highway driving, imo lower engine temps far outways fuel consumption and emissions.

 

Sounds like there is/was some blockage in your heater core. We run a 180 t-stat and the heater will drive u out on max. This time of year, coolant temp runs 180-187 (ScanGauge).

I don't understand the cooling system "burping" issue/problem on open type systems.

1. Fill the rad full and overflow bottle 1/2 full with coolant
2. Start it/let it idle with rad cap off
3. Keep the rad filled as coolant level drops
4. When coolant flows out rad, put the rad cap on, done

Next day, ENGINE COLD, remove rad cap, add coolant if needed.

 

there is alot of over thinking going on in the thread. a T/stat doesnt cool anything. its the switch that allows you engine to reach operating temps faster. but allow cooling to happen when needed.

the t/stat only allows the cooling system to start flowing. if it oppens at 160* it will take a little while longer to reach FULL operating temps, and will allow it to cool longer before eliminating the flow. 180* will reach full operating temps faster. but once there open they will cool as efficient as eachother(the rest of the system of what causes cooling effitiency) one just starts soons and stops later then the other. the actual cooling that takes place will be the same when open. ive always had a 180* t/stat, but when i am towing, or going up a canyon i reach a bit higher temps... like 220* ish... so i dont want it to stop cooling so i switched to a 160* T/STAT. runs great. warms fast. cools the same other wise. but when towing and going up steep grades it sit right at 205-210*. i wouldnt recommend lower then 160*, but i wouldnt run higher then 180*. if i could find a 170* i would think its was best...

 

As stated in post #4, the t-stat only controls minimum coolant temp. What's full operating temp? This time of year and for the next several months, coolant temps will top out at, or slightly above, the t-stat temp (normal driving conditions).

 

full operating temp is when the ecu stops running a preset program and uses the sensors to control fuel/timing ect. if the vehicle doesnt warm up to "full/normal" operating temps its wont use live info to create most power/mpg ect...

 

If referring to "closed loop", OBD-II will enter closed loop with-in a few seconds of engine start-up, as soon as the heated O2(s) reach operating temp.

 

djb383, I am not saying that these cooling systems ARE actually that difficult to fill. I just wanted to make sure that there wasn't going to be anything I could have missed. So i painfully went through the burping process. I agree is should just be a matter of filling the radiator and the overflow, let the themostat open and refilling.

As to the heater core being clogged, I am confused. I ran a garden hose through it and it ran through without issue and clean. Could it still be clogged? I have heat now but not what I would call great heat.

 

Yes, the heater core (rad too for that matter) can get a internal build-up that just can't be flushed. Coolant will flow but at a slower rate and the build-up acts as an insulator......not allowing the heater core or rad to loose/shed heat as effectively. Some have suggested using CLR to flush the heater core. I have no experience using CLR so can't help there.

 

Well I finally think I have it fixed. I thought I had it fixed last weekend after replaceing the 160 Degree thermo with the 195 and spending a lot of time burping it just to make sure.

After my son drove it over the week he said slight heat but not real heat.

So I bought more anti freeze and some CLR. I did the routine shown on Youtube. I didn't really expect it to make any difference since I had already flushed the heater core weeks back with the garden hose and the core was totally clean and flowed no problem.

I was shocked at the crap that came out of that core back flushing it with the air. I did that many times and then put in the CLR for a half hour. I then continued to flush and get more crap out. I flushed until nothing came out.

Refilled the radiator and overflow.

It is putting out real heat now.

 

Excellent.

 

I have heard of positive results with "containing" the heater core and filling it with
either vinegar or CLR.

Heater cores (especially in vehicles where the cooling system isn't maintained properly) can clog up.