Best approach for "elusive" car problem

I have a car about 11 years old with 107K miles. Since last winter, it would intermittently and briefly make grinding noise on cold start ups. It does not happen on all cold start ups, and when it happens, it would last few seconds, and stop, and maybe few seconds later come back again for few seconds. Noise it not consistent at all so it’s very difficult to duplicate the problem when taking it to a mechanic, and mechanics will say unless the noise is consistent and they can duplicate the noise, it will be very difficult to isolate the problem or diagnose it. During warm weather such as now in May, it doesn’t happen. It only happens in cold weathers. I did go to two mechanics, and both worked on my car, and didn’t fix my problem so I payed two mechanics w/o getting my problem fixed.

What would be the best approach about how long to keep this car? It will need new tires, battery, bunch of other maintenance work, and w/in next 5 years it will likely need new clutch, and clutch along will be over $1000 in my area. Given car’s elusive problem which doesn’t yet seem to be affecting its driveability, should I keep putting money into it to maintain it, OR do nothing until a bigger problem happens, OR start working on getting rid of the car with least financial damage? Your opinions are appreciated.

If it only happens when you have the key turned and the engine is cranking, it sounds to me like it might be where the starter contacts the engine at the fly wheel. The teeth may not be mating well. If it is the starter, replace it now. If the noise continues happening even after the car has started and you have let go of the key, even for a second, then it is not the starter. When the engine turns, it causes the drive belts to move the power steering pump, the alternator, the AC compressor and the water pump are turned. It is probably the bearings in one of those and it only happens when it is cold b. If you have a second person who can start it for you while you lean over the engine when you start it, and you can get a better bead on it, you may be able to figure it out. Another thought is, if you take off the drive belts, and then start it, and there is no sound, then it is definitely one of the things that the drive belt/s drive. Any of the things I mentioned can be easily replaced yourself with simple hand tools with a replacement part from a place like AutoZone or, if you are really cash strapped, a used one from the same make/model/generation vehicle at a junkyard. If it is the bearings, it will keep getting worse to the point that it happens overtime or all the time. If it is the starter better replace it soon because it could be causing internal damage to the flywheel.

“If the noise continues happening even after the car has started and you have let go of the key, even for a second, then it is not the starter.” In that case, my problem is not the starter, but more likely to be a bearing someplace where the serpentine belt spins on. Can a bearing make sporadic grinding noise in a cold start up in cold weathers only? If it is the bearing, and I do nothing, what should I expect will eventually happen? This sporadic grinding noise started few month after getting my alternator replaced. My previous alternator had died.

It could be the starter not disengaging. As for your 11 year old car of unknown condition and the unknown amount of miles you drive and the unknown state of your finances, I would have to say…I don’t know.

The thing is, a noise could really be anything. You’re really gonna have to pay more attention to what it could be. Instead of the starter motor grinding, it could simply be the idler pulley on the belt tensioner. About $20. Or alternator or steering pump, or something in the engine. You’re going to have to isolate it more-left, right, front, back of the engine compartment, etc. Worn or dry bearings will make more noise when they are cold.

I’d have the mechanic check for anything loose in the exhaust system, heat shields, brackets, the catalyst inside the converter(s) (checked by rapping on the outside), etcetera.

Sometimes “grinding” is a rattle and they are often intermittent and temperature related.

“I have a car about 11 years old with 107K miles.”

Make and Model, please?
CSA

What kind of car and what year? It could just be a bad ground or solenoid or battery. Cold temps can raise hell with electric parts the fact it only happens in the cold tells me it something simple I would start by checking electric connections and then test the the lines for conductivity

So this grinding noise continues even after the engine starts, the key is returned to “on” and the engine is idling? It could be a major problem, like one of the main crankshaft bearings or piston rod bearings are deprived of oil for some reason. That could certainly happen more when the engine was cold than warm. The oil doesn’t flow as easily when cold and the engine part dimensions are affected by the temperature. That would be unusual to happen for a modern engine maintained in accordance with the schedule shown in the owner’s manual, and with only 100K miles on it; unless it had ever run low on oil or overheated. Have either of those two happened?

If not, it’s probably something that is easy to fix, but hard to figure out what’s causing it. If I had that problem I’d test it every cold start. I’d ask an assistant to start it up while I used a length of garden hose, wooden dowels, etc as stethoscope to try to localize where exactly the noise is coming from.

Your shop can do that too, but you’d have to leave the car with them so they could start it up early in the morning when it is still cold. They might need to keep it for weeks or months to eventually diagnosis it. Which is why presumably they are telling you to wait until the noise happens all the time. But if you don’t mind not having use of the car for a few weeks or months, you could take it to the shop and leave it there until they finally figured it out.

??? What kind of hell does it raise?

I’ve lived in a location that has some fairly substantial cold weather (down to -40F) for over 30 years.

The cold has not raised any hell with any our cars’ electrical parts.
CSA

I’m guessing the poster above is referring to the battery. Battery output power is reduced when cold.

So. That’s a “given.” For years manufacturers have been stating CA (Cranking Amps) & CCA (Cold Cranking Amps) on car batteries.

I’ve not had a car fail to start, even when relying on the CCA, and I’ve not had any electric components go to hell in a hand basket when it gets REALLY cold.
CSA

I’ve had cars fail to crank when it gets really cold.

Then something else is wrong! Trust me. I’ve lived above the 45th parallel for over 30 years and my wife and I each fired off our cars long before sun-up all those years, setting out on 35+ mile drives to work (one-way). Many days here it never reaches 32 degrees, we’ve gone a week or 2 not reaching zero.

I just got done playing golf on the Tuesday night league, 45 degrees!

If your car won’t crank then something’s haywire.
CSA

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We need more info. Year make model miles engine size, history (was quiet, changed alternator, poor charge) .

A point which is hard to deny … lol … I’m not disagreeing w/you in principle CSA, you are right that electronic components tend to fail more when they get too hot than too cold. But the basic physical principles which describe electrical current flow almost always have temperature components in the equations. And most circuit components are rated for both maximum and minimum temperature, outside of which they are not guaranteed to function to spec.

Some people think 40 degrees is cold. Others of us don’t consider it really cold unless it is below zero, like ten below zero. Lol.

I’m trying to think of an electrical problem with a car of mine caused by it being too cold, other than cranking with a weak battery. I did have a cranking problem caused by something other than the battery’s electrical properties one time. The battery post got smaller when it got cold, and wasn’t making a good contact with the connector. Tightening the connector fixed that one. hmmm … what else? The heater fan in my truck sometimes wouldn’t work when it got really cold in Colorado, caused b/c the cage is hitting something that shrinks enough to cause an interference I think. I’ve had ventilating fans (for an apartment window) fail to start when it is cold, presumably b/c the bearing lube gets more viscous, but that isn’t an automobile thing. I’d guess that an automobile relay or electrical solenoid might get sticky and fail when cold, but I’ve never had that occur.

These are the parts temperature grades electrical engineers have at their disposal when designing product circuity.

Commercial 0°C to 85°C
Industrial : -40°C to 100°C
Extended: -40°C to 125°C (1)
Military: -55°C to 125°C
Automotive: -40°C to 125°C (2)

I’ve owned cars where I live that at very cold temperatures (usually below -20) “scream” when they’re started (bearings, belts ???) . It sounds like the end of the world. I’ve had radiator hoses dribble coolant and power steering that gets very stiff. Sometimes seats are hard as a rock, tires feel square as you drive off, etcetera…

However, at first these things are alarming, but just like Norm’s under-shorts on Cheers (funny episode!) they self-correct after a while.

I agree with temperature related issues, but our cars always fired up, ran, and took us to and from wherever we were going. We had no choice and the cars were up to it. You grow accustomed to it after a while and know what to expect and what is “normal.”
CSA

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The physical post shrinking in the cold isn’t an electrical problem, though :wink: Makes me glad that I don’t live in places where significant periods of -10 is normal, though!

Me too! Oh wait, I live in that environment. :neutral_face:

it wasn’t too bad when I was younger and worked indoors most of the time, but I’m a few years into understanding why the “Snow Birds” head for warmer locations. That’s what I’m going to do. The extreme cold can take a toll on an aging athlete. Plans are in the works. :blush:
CSA

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