A couple random questions

First question: Does anyone know if there is any reason cold weather makes car lights go out? Just wondering because when we got our first big storm of the year in OH, one of my headlights went out. This weekend we got another one, and the other one went out…Of course the more obvious reason would be that my car is now 5 years old and it’s about time for something to go out on it… :slight_smile:

Second, and more important question: I just noticed today that my car is making what I can only describe in writing as a sort of “growling” noise when I accelerate…It’s most noticeable in 2nd gear, but it is there somewhat in all gears, and seems to peak a second or two after I back off the gas…I am guessing it’s my muffler, but I am just curious as to what other things can cause such a noise while accelerating. Nothing else has been going on with the car (2003 Nissan Xterra 4L), other than a gradual decrease in gas mileage, which I am guessing is to be expected as it gets older. No check engine light on, etc.

First answer: The rule of thumb is to replace both headlights if one goes out. If one went out, the other is not far behind. Cold weather may be a factor, since the temp differential will cause more start-up stress, but, being 5 years old, chances are they were ready to go anyway.

Second answer: hopefully it is an exhaust noise. But, with the extensive use of stainless steel in modern car exhaust, it could be something worse. Make sure the fluid levels in the transmission and differential are good. Also if this truck is 4WD, also check the fluid in the transfer case and front diff.

#1 Yes, The temperature difference when they turn on (thermal shock) and the fact that you drive far more in the dark during winter so they get more wear and are more likely to burn out.

#2 Auto or manual transmission?

There may be error codes stored even without a light. Cold weather causes reduced mileage directly and indirectly

I have a personal view of bad lights that seems to anger a lot of people. Due to changing legal issues, I am convinced it is a good idea to change all external lights at a certain point, not just pairs as the first one fails, which is sort of the traditional viewpoint.

A California attorney some months ago informed the Sienna Club that in California, a bad light is now a moving violation, just like speeding, to be reported to your insurance company as such and to pay a fine. It is cheaper to replace the bulbs before they fail.

Also, law enforcement aggressively tries to search vehicles, though the Supreme Court ruled in Knowles v. Iowa in 1998 they do not have that right for minor traffic stops. But, they proudly announce on their URL’s that they get to steal 1 out of 20 cars they search. And, burned out lights is high on their list for probable cause to stop. To me, it simply isn’t worth the hassle, just for a few light bulbs. Others can certainly make their own minds up on this.

Several years ago, I asked when was the reasonable time to replace everything. I really invoked flames. Quite a few people honestly believed lights simply don’t burn out any more. So, I let it go, and on my Toyota Sienna at 84,000 miles the high stop light died. Fortunately, I caught it first. Then, I replaced everything, and when my daughter-in-law had a burned out bulb, I replaced all of hers as well.

So, I have decided to replace all lights at around 70,000 miles and be done with it. Everyone else can do as they please on this.

Thanks Joseph, it’s a 2WD, manual

Thanks BK, I will check those tomorrow. I went to 2 auto parts stores today to see if they’d retrieve any codes, and apparently they’re not doing that any more. So if the fluid levels are fine I may have to take it in. It seemed to be doing it less as I drove around today but maybe that was just wishful thinking…

In addition to the temperature cycling and thermal shock to the filament that others have mentioned, in the winter the days are short and the lights get more use. Except mine. I always drive with my lights on, rain or shine.

First: I think the weather could be a factor in light bulb life. The only lightbulb that has burned out in my car is in the dashboard. My car is ten years old and I live in Florida.

Second: If the sound peaks a second or two after you let off the accelerator, I would not describe it as “a noise while accelerating” since it is more pronounced when you are not accelerating. Nonetheless, the delay indicates that it may be an exhaust leak.

Lastly, I don’t think it is normal for a well maintained car to experience a measurable decrease in fuel economy. A noticeable decrease in fuel economy is a symptom of either a malfunction or a lack of maintenance. How often do you replace the air filter, spark plugs, and spark plug wires? How often do you change the oil? How often do you check tire pressure? How often do you clean the fuel system?

I have a personal view of bad lights that seems to anger a lot of people.

I think this approach angers some people because it lacks logic and is totally based on fear. The idea that the police will somehow try to seize your car because you have a burned out light is preposterous.

Yes, police sometimes target folks with burned out lights. This is a good reason not to procrastinate when one burns out. It is also a good reason to conduct a cursory pre-trip inspection. It might also be a good reason to carry a spare bulb. Is it also reasonable to pull every good bulb and replace it just in case? Maybe if you are paranoid and obsessive-compulsive.

Trust me. This is wayyyyyyy over the top no matter which way you look at it.

Hi Jeremy,
I thought it was just normal for a car’s gas mileage to go down a bit as it ages, but I’m glad if it isn’t! I do all the normal maintenance, w/oil/air filter changes/tire pressure etc. I took the car to an awesome shop I’ve been going to for years in TX for a general tuneup when I was last there, told them about the mileage decrease, and they told me that as I had platinum spark plugs, that they’d be good until about 75K, which I am almost to right now (they also asked about maintenance and if any check lights were on, which they weren’t, and then that seemed to be the end of their ideas about that). Does that sound right- change those out at 75K?? I haven’t had the fuel system cleaned - is this something I can just ask them to do, and about how much does it cost? Thanks for all the ideas- I really appreciate it!!

The longer life of spark plugs are normal for most new cars. At 75,000 miles, I would replace them and the spark plug wires. About cleaning the fuel system, I pour a bottle of fuel injector cleaner or fuel system cleaner into the gas tank every time I do an oil change. I also change my fuel filter every 30,000 miles. A service rep. once told me that what I do is like brushing the car’s teeth. He said that the fuel induction service that he sells is like going to the dentist. I have never had the fuel induction service done and I consider it a repair more than a maintenance item. Most name brand gasolines have detergent in them, but not all of them do and most of the cheaper off-brands don’t. If you haven’t been using fuel system cleaner or fuel injector cleaner, you might try doing it with your next few tanks of gas to see if your fuel economy improves. It really doesn’t matter which brand you choose. However, with an SUV like yours, look for one that is packaged for large vehicles like SUVs and minivans. The smaller bottles might require you to use two of them in a single tank of gas with a large gas tank. Make sure you read the directions thoroughly. The fuel injector cleaners are obviously made to clean the fuel injectors. The fuel system cleaners, however, are made clean the whole fuel system including the valves and other components. That is why I alternate between the two. A lot of people think this is overkill, but it gives me peace of mind. If it helps you, I will feel vindicated.

Thermal cycling and thermal shock are definitely factors in a filament life. I speak from the perspective of actually having written and performed the qualification and design validation test protocols for a UV sensitive tube that used the same tungsten filament wire as is used in incandescent lamps. And then done SEM analysis on failed filaments. Our application was on a shrouds of the GE and Pratt & Whitney turbine engines used on fighters, F14s and F16s if memory serves. The testing was, as you can imagine, heavy on heat-vibration, thermal cycling, and thermal shock.

And I agree that a decrease in gas mileage is not a normal part of aging. I’ve owned vehicles from new to up to 338,000 miles and my mileage has never decreased significantly, although I think my last pickup might have been losing some pep as it approached 300,000. The oil rings were still holding, though, it never burned oil.

If a store won’t scan for the trouble codes, it’s cheaper to buy a scanner, and do it yourself, than it is to pay someone else to do a code scan.
To do a full scan, and look at the sensor outputs, is a different thing. I suspect that some shops just do code scans.
Whichever you do, bring the codes back here.