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What do I tell my mechanic?

I’m an elderly woman in very rural Nebraska. My (bought new) 2011 XTerra is perfect–EXCEPT that the heater does not work when it’s not moving. (It never did, but I had already taken it home.) This means I can’t warm up the car before I get in. If I happen to stop or get stuck it blows only cold air. It blizzards out here, guys, and at minus 20 I can’t leave Dolly the dog sitting in the car at all. I’m sure this is NOT supposed to be happening, but the only Nissan dealer is 250 miles away, and when called they give no info but only say “bring it in right away.” I have good mechanics only 70 miles away, but I’d like to give them some clue as to what to look for and where, so that I don’t get trapped with my dog 70 miles from home while these guys tiddle with the innards of my heater. If I have to, I’ll go to the dealer, but I’d sure like to know what to expect and how long they’ll have to keep the car. I’m pretty sure this is covered under my first 3 years bumper to bumper, but it will cost me big time in travel and time. Can anybody help?

Have the thermostat checked to see if it’s functioning properly. If it is then have them check the coolant level. The problem you are having usually relates to low coolant and air in the coolant system. A good mechanic should be able to fix the problem easily at very little expense to you.

Well, it seems you’ve discovered the biggest caveat to out of town car buying that I always stress the most. Buying locally has its merits as I always advise our locals…“I don’t mind if you don’t buy a Ford from us, but at least buy locally if at least for sevicing’s sake ( and the local economy ).” Other brands have to be towed or taken to Albuquerque or Phoenix.

The malfunction sounds as if the blend doors are vacuum operated and there’s a vacuum leak.
This can be anywhere. Hoses, tubes, switch, vacuum actuators etc.
A mechanic will perform a smoke test to find the leak.
You could perhaps listen around the various areas of the system for a slight hiss, but I doubt you’ll hear anything.

Absoluitely follow Missileman’s suggestion. Be sure everything is working right.

However, I have to add that when I lived inm North Dakota I discovered that the average engine will not generate enough heat at idle to warm itself up at -20F. We used two solutions; (1) we installed plug-in heaters for the engines and plugged them in overnight, and (2) we’d cover part or most of the radiator with cardboard or a piece of blanket.

If your mechanic finds everything operatting properly, ask him about these ideas. Especially the engine heater.

Thanks, Guys! I wonder if any of you heard Tom and Ray’s answer to the “when the wheels aren’t moving it doesn’t heat” problem some months back involving a Nissan Quest. I didn’t catch the whole answer (and of course didn’t write it down) but I believe I heard the words “simple” and “valve in heater.” It sounded like the same thing I’m experiencing–but I can’t track it down.

@Prairie Peg: are you able to check the coolant yourself, or have a neighbor who could do that? If missileman is right, then you may be able to solve your problem without that long drive.

All you’d need is a jug of coolant, which you might be able to track down locally at a farm supply business, or get someone to purchase some for you on a trip to town. If you do it yourself, you want to use a 50% solution, so either buy premixed coolant (that’s the simplest way) or mix whatever coolant you get with water. Be sure the engine is COLD before you remove the radiator cap.

You may be on the right track with the heater valve, but I would think that if that were your problem, that you wouldn’t get much heat any time, moving or not. Start with checking the coolant, then ask the dealer why your NEW car had insufficient coolant.

I never heard the show, but I know how cooling systems work.
I also know from personal experience about the unique problems of -20F.

Basically, 100% of the heat that heats your car inside comes from the engine’s coolant.
100% of the heat in the coolant comes from the explosions in your engine’s cylinders that runs the engine. The heat from the coolant is disipated by the radiator, some of it going thorugh a seperate little radiator thatt removes heat from the coolant and blows it on your feet.

Under normal conditions, the engine generates more heat even at idle than needed to heat the coolant to full engine operating tenperature, typically about 200F+. A valve called a “thermostat” opens up allowing the heated coolant to flow through the radiator, where it gets removed.

However, the concept is that heat moves from a warmer mass to a cooler mass. If the outside air is 80F, the engine can heat itself up and then open the thermostat and pass heated coolant to the radiator for more heat removal. If the outside temperature is -20F, the heat will be being drawn out of the engine’s sides at idle faster than the cylinders can heat the coolant. The engine won’t warm up. An engine generates much more heat when operating at higher RMPs (more explosions) and when under load (bigger explosions) so it may heat up when driving it.

In some cases, the air will be so cold that the minute the thermostat opens the radiator cools the coolant down too low to allow the engine to warm. The blankets or cardboard we used to use to block the radiator kept air from being drawn through the radiator and reduced the cooling, allowing the engine to warm.

Forget the words “simple” and “valve in radiiator”. They won;t help you.

Take it back to the dealer. Its their problem. Either the coolant is low, its not getting up to operating temperature, or the doors in the heater aren’t functioning properly. Tell the dealer the same thing you said here. Don’t they give you a car to use when they are working on it as a new car customer? I wouldn’t let a non-dealer start messing with it during the warranty period.

Bing, I agree wholeheartedly that it should be brought back to the dealer and looked at. I also agree that a warranmty ehicle should not be brought to an independant mechanic.

However, if it checks out okay it’s important to understand that in sub-zero climates compensation such as an engine heater and/or a blanket may be necessary. Things are different at -20. It can become a struggle for the engine to get itself to operating temperature. The car may not be defective after all. Been there, experienced that.

Take it back to the dealer. Its their problem.

@Bing
I also agree that it would be best to get this back to the dealer. However, the OP stated she is trying to avoid the 500 mile round trip to the dealer. If all that’s wrong is low coolant as missleman suggested, she need not waste the time, expense, and inconvenience merely to have the dealer fill the radiator. Of course this may be a sign of a deeper problem in the cooling system, in which case the dealer must get involved, unless the issue is what mountainbike suggests.

We were faced with a problem with a problem with a new vehicle. We bought a Toyota 4Runner from a dealer 25 miles from home. The vehicle developed a terrible chirping noise. We went back to the dealer at great inconvenience five times. Each time, the dealer blamed the serpentine belt and replaced the belt. On one the replacements, the technician didn’t put the belt on correctly and it pulled out the crankshaft oil seal. After the crankshaft seal was replaced and another new belt installed, the chirp returned again. My wife wanted to take it to our independent shop even though we would have to pay the repair. I said that the vehicle was warranted and I took it back and was very firm. I told the dealer that they had one chance left to make it right, or they would buy the vehicle back under the lemon law. I also said that this time they were to provide a car for me to drive. I told them to keep the 4Runner until it was right. This time, the problem was solved. It was a defective belt tensioner. We still have the 4Runner 9 years later and have had no problems since. I have also never been back to that Toyota dealer.
Yes, one needs to go back to the dealer with a warranty problem and I think that is what the OP should do. However, my wife and I were both working at the time and going to the dealer was a great inconvenience. I am certain that our independent shop would have found the problem right away.

Hmmm, missed the 250 miles to the dealer part. I thought it was 70 miles. That would be a problem unless a major issue was found. Guess you’re on your own.

Here’s a simple test that might reveal something about the cause. The next time you drive it and the problem occurs, pull over and put the car in park.

Put the heater fan on medium speed and select the dash vents. Is it blowing cooler air out the dash vents? Is it forcefully expelling the air as you would expect for that fan speed?

If so, press the gas pedal enough to rev the engine and hold it there. You want to reach the normal engine speed while driving, this will be a lot less gas pedal travel than while driving because there is no load on the engine. Maybe 1/8 to 1/4 down.

After about 15 seconds, has it started to blow hotter air through the dash vents?

Post back your results…

Whoops! I missed that mileage problem.
Under those circumstances I take back everything I said. If there’s a close and trustworthy independant shop, it’d be prudent to have them take a look-see. It’s also prudent to have them do the scheduled maintenance abd SAVE THE WORKORDERS as evidence that the maintenance schedule has been complied with.