I was driving in -30 degree weather when the vehicle's check gauge light came on. The temperature gauge needle was rising near the red line. I pulled over to let it cool down. Smelled anti-freeze in the cabin, could taste the sweetness on my lips. Once it cooled down, I drove it the rest of the way home and parked it. Steam was coming from the front of the vehicle, looked like it was on fire in that cold air. Let it cool down. Once I popped the hood, noticed that the coolant reservoir cap had popped open and it sprayed anti freeze all over the engine. I figured that it was a bad thermostat. I removed it and tested it in a pan of boiling water, it opened in the boiling water, and closed as it cooled down. Put the thermostat back in, filled it with coolant, burped the system, and drove it around until the engine reached normal operating temperature. I noticed that the temperature gauge would climb up to the middle, as it normally does when the engine heats up, and then drop down towards the cold on the temp gauge? Also, the heat would fluctuate from warm to cold when it did this? So I replaced the thermostat and gasket. Same result? Brought it to a local garage. They tested for head gasket leaks, none found. They said nothing wrong with the water pump. They replaced the thermostat and gasket again. Same result. They used a vacuum tool on the coolant system, said that it was good. I personally spoke to the auto tech and he told me that he thought that the heater core needed to be replaced. Talking about spending more than ole' trusty rusty is worth, lol! So I've been driving it around for a few days, the heat has gotten hotter, but it still fluctuates with the temperature gauge from hot to warm? Any ideas what to look at next?
During those extreme conditions, super-cooled fluid from radiator might cause those conditions. Or, the thermostats that have been installed don't work like the old one. Like cheap and easy? Put some cardboard in front of radiator to keep the temperature fluctuations more moderate.
Thanx for the reply! I will try the cardboard trick when it gets that cold again.
I went to Napa to get the 1st thermostat, all they had was a 180, so I tried that. The repair shop put in a Motorcraft 195 thermostat.
I find it strange that the truck didn't have any problems last winter, and it got that cold on some days? The coolant system was flushed and replaced with 50/50 green coolant this past spring? There wasn't any signs of any problems, until THAT day?!
A buddy of mine, not an auto tech, told me that there are 2 sensors on my truck that are for the coolant. He said that 1 is a coolant temperature sensor, and the other is a sender that sends a signal to the temp gauge? He says that they rarely go bad, only if an engine overheats. Could one of those be causing the temp gauge & the heat to fluctuate?
A sensor connected to the computer would most likely cause problems with starting, stalling, bad gas mileage. A sensor connected to a gauge might cause the gauge to give inaccurate information. But, sensors will not cause fluctuation in heater output. If heater output goes up and down at the same time that the gauge goes up and down, the gauge is probably working OK.
The most common cause for heater output fluctuation is low coolant. Lots of variables to consider for a more general complaint of "my heater doesn't work as good as it should". The definition you have given of your problem is more specific (and unusual).
I've been wondering if the 50-50 antifreeze mixture was just a pinch off. Chart for 50-50 shows something like -35*F freeze point. If you were at -30*F and there was water left in the system before it was added... Where I'm going with this: Could the Radiator have frozen partially, limiting circulation and forcing the system to boiling? As Dan said, Cardboard would be enough to prevent that. Keep
Well, -30f is close to what we get up here often. In our parts, that is -34c. So 50/50 solution is ideal. When I was working up north in the tundra, we had to go 70/30 for -55c temps.
So as JD wrote. Try to get some cooling strips from your local shop and test the coolant. Cheap. They can probably sell you one for a buck or two. That way, you can check acidity too at same time for freezing point.
After three or four stats, I would stop fussing with that as you are just intruding more and more air pockets in there and having to continually burp the system. Heads have been tested ok. T-stat is definitely ok after 4 or so.
I realize the coolant was replaced last spring, but check it anyway. As for the cardboard trick, sure why not. But I do know they sell front grill covers with a flap for these trucks just for conditions like this. We use these on ALOT/ A TON of trucks up here. Very common to see them. They should look like this.
That way, if you feel you are getting too warm, just open a flap or two to get some airflow. Or, just make your own out of an old vinyl sheet of some sorts. But you would need to be a seamstress and buy some velcro or buttons and blabla. Cardboard doesn't last too long up here. It just ends up disintegrating and getting in the condenser and rad fins and a heck of a mess to clean up when shyte hits the fans due to that. Yes, the pun was intended.
So if you do go the card board way, change that out very often.
If you like old rusty or whatever you nicknamed it, the local Walmart probably has something that looks like the above picture. Just type in winter front grill cover on google, bing, or yahoo or fart a joke research engine type thingy that is kinda like I am feeling lucky today sort of thing. Tons of them on line.
If your heater core was clogged, you wouldn't be getting any heat period.
If you are getting fluctuating heat, cap for some reason was open, engine overheated, that is just air in the system. Cap was probably put on wrong at some point. A regular car/truck OEM cap does not just pop open for any reason. Unless you have one of those stant pop lock caps that some ppl enjoy putting on their pride and joys. Usually see that in southern trucks and such. I am NOT a fan. Any idiot can pop that safety release valve with his/her shirt sleeve and not know it. They are merely a safety feature that is appropriate to have in hot environment's where engines are more likely to overheat. Up north, no use for that.
There is a procedure to properly "burp" and engine. For a ranger, quite straight forward.
So that was my , but hey, opinions are like arseholes, everyone has one.
A great big thank you to all of you that have replied! As I've been driving the old ranger around the past days, the heat has gotten hotter in the cab. Outside temps have ranged between single digit fahrenheit temps into the 30's. Sometimes, on longer trips, I have to turn the fan down to the lowest level and also turn the temp down on the temp control knob? The needle on the temp guage still tries to drop down, but now, instead of cold air being blown through, it's just not as hot air? I still haven't tried the cardboard trick yet? I've been checking the fluids to see if anything is dropping low, but the coolant, oil, power steering, brake fluid levels remain steady? I don't see anything leaking under the truck either? Did it fix itself?
I'm back again After driving her around since my last post, the heat in the cab has been sufficient, although it's still fluctuating with the temp gauge? I've noticed a difference in the starting of the vehicle as well. It seems to take more cranks to get it started now, and the idle has not been the same. The idle gauge bounces from time to time, sometimes the needle just stays all the way down? It's been warmer here, around 30, higher or lower on some days. Today, it started up just fine, and I drove it for about 10 miles without any problems. Put her in park & shut her off to go into a store. She started back up just fine, but after I drove for about a mile, she started to sputter or hesitate, could see the hood bouncing up and down when it did this. I pumped the gas pedal a few times and she would return to normal? This condition kept coming back and I kept having to pump the gas pedal? I did this for about another mile before I could pull over. When I pulled over to pop the hood, I couldn't smell anything or see anything wrong with her? The strange thing is, I put her back in drive and drove her for about 12 more miles, the sputtering or hesitation condition didn't return? I also noticed a gas mileage issue. It sucked up about 1/8 of a tank in my travels today?
Update: I drove it around today without any problems, except the temp gauge issue remains. Had the codes read on it too. It had a P0455 & a P0174. The P0455 code has been there since I bought the vehicle. The purge valve, the canister, and the solenoid has already been replaced, but the code keeps coming back? A friend told me that these vehicles have an issue with a piece of rubber hose above the fuel tank that rots out and can cause the P0455? Our local garages wont even touch gas tank issues, and it drives fine with that code, so I've learned to live with it. The P0174 code is a new one, and I'm assuming that it appeared the other day when I had the sputtering/hesitation issue with the vehicle? I searched the P0174 code on the internet and it seems that there are a lot of possible causes for this lean condition in bank 2. I'm going to replace the coolant temperature sensor in hopes that it clears up the temp gauge issue. But I'm pretty lost on the P0174 code? Where is the oxygen sensor on bank 2 located?
Another Update: I replaced the coolant sensor. It broke in half while I removed it? The deep well 19mm was all the way down too? I also noticed that a hose wasn't connected to the air intake. I recently had a quick 10 minute oil change done, they might've just bumped it?
Bank 2 is always opposite the side of the engine that houses cylinder #1. In your case, that is passenger side (cyl #1) making bank 2 on driver side.
That lean code sure would account for going through all that gas and the sputtering you encountered as the engine was enriching itself, hence possibly cooking the catalytic convertor due to raw fuel dumping in there.
That hose that wasn't connected to the air intake would surely have caused that. But normally, that should have affected both banks.
Focus on bank two intake and exhaust leaks and the o2 sensors. If you have a crack in exhaust manifold before the o2 sensor, that will code a condition as the sensor is not seeing all the exhaust gasses and will report back. Also a clogged fuel filter will code (again, usually on both banks), clogged injectors, vacuum leaks at intake manifold etc.,
This could take quite some diagnosing. Report back once you have driven it for awhile with a new coolant sensor and that hose at air intake plugged back in.
If you can, post live data and tell me what fuel trims are. They are shown in percentile or -/+. STFT and LTFT. In your case, that freeze frame would have shown a + 25% short term and long term as the engine algorythm was adding fuel due to a lean condition.
So when you see a -, you are in a rich condition, and vice versa.
Hope that helps, if code comes back, I will post the whole trouble shoot chart, which BTW is very long and labor intensive for the beginner.
But, I will walk you through it. But I feel that hose that was disconnected may have been the root cause. Especially if it was after the MAF (mass air flow sensor).
Thank you for the reply! As I've been driving around, the hesitation has not returned yet. I had a friend read the codes again and it only shows the P0455. Replacing the coolant temperature sensor has had no effect on the temperature gauge needle fluctuating either. I'm thinking about replacing the sender. It's a cheap part, so why not?
So bank 2 is on the drivers side and the sensor is in the exhaust? The exhaust is a bit loud, but it sounds like it's coming more from the rear of the vehicle? A lot of salt gets dumped on the roads here in the winter time and it wreaks havoc on our vehicle exhaust systems, among other things. That hose that was unplugged was indeed after the mass air flow sensor.
I have no way of providing live data, but I wish I could. Maybe I should invest in a good OBD2 code reader? Thank you again for the help, I will keep you updated if the hesitation or code P0174 shows up again!