|Topic Review (Newest First)|
|06-15-2019 06:37 AM|
The problem with TPMS is caused by the regulatory implementation not any inherent problem with the capability of the system.
The higher specification valve stem transmitter system is the one prone to false fault warning light triggers. It's also the one that could have been implemented without the need for any warning light. Like the electronic dipstick the primary reason for these TPMS was consumer driven. The implementation was dumbed down accordingly.
It starts with the development of run flat tires, arguably a solution looking for a problem given the exceptional reliability of modern tires. Federal authorities were concerned about the very advantage delivered by runflats, ie that the driver could continue without being aware that the runflat tire was in fact flat. Ironic really. Therefore cars equipped with runflats as delivered from the factory had to display a fault light if a tire lost air pressure even though it remained safe to drive on.
After the Firestone scandal these systems were made mandatory for all passenger vehicles. But not up here in Canada.
The most sophisticated type generates an actual temperature and pressure signal fed to a TPMS ECU which converts those two bits of information into a warning signal when the algorithm produces a number more than 20% lower than a reference value programmed into the system. That is already dangerously deflated but using a safer smaller number leads to almost continuous fault display. As implemented as a safety system on regular non run flat tires TPMS is actually dangerous for this reason.
Now these same valve stem sensor transmitters are extremely accurate and reliable. On racing cars they deliver real time actual tire pressure and temperature values, and can be retransmitted to the pits or indeed to a very remote factory along with all the other telemetry modern automotive technology permits.
Some makers have utilized this high performance capability to actually display tire pressures to the driver. Porsche was probably the first to do so. But, like the analog dipstick (that's the metal stick in the tube) the driver needs to understand what the system is telling him or her. That's the weak link. As you drive the actual tire pressure increases, by quite a lot. If you use a TPMS that displays actual pressure you need to know what the correct range is as your tires heat up.
In Canada I suspect we do not require TPMS because severe climate conditions would mean the TPMS fault would be on and off apparently randomly to an unsophisticated driver. Actual tire pressure varies by about 5 psi for every 1 C (2F) change in the ambient air temperature but also by the same proportion as the internal temperature of the tire heats up. In my city winter temperatures can vary from as much as minus 30C to plus 20C in a single day. TPMS is pretty much useless in such conditions. So we aren't required to have it.
These electronic systems are robustly reliable. But users stil need to know what they are being told. Oil level sensors could display actual oil level rather than just "OK" or "add" but they aren't used in that way. Oil level in the sump varies a lot with a variety of factors which is the main reason so much extra oil is in there to begin with. The average car engine needs about a litre (or quart if you prefer) of oil to run safely. The rest is there as a heat sink (an oil cooler would be more efficient) and a reserve to cover the oil pickup under all likely conditions (a dry sump system is preferred).
It's nice to have displays for information like engine oil pressure, oil temperature (still the most useful warning gauge), coolant temperature, tire pressure, engine rpm, vehicle speed (the least useful dashboard instrument for driving is a speedometer which is why racing cars don't have one) and so on. But it takes a knowledgable driver to utilize this information properly. So modern cars have dropped most of this capability to inform the driver. Driving is continuously being dumbed down, ironically for safety. The objective of regulators is to fully automate driving.....
|06-14-2019 05:46 PM|
Originally Posted by GV27 View Post
Yeah, definitely worse than a sodding tire pressure sensor that is wrong. At least a piece of tape or a picture on the dash fixes that!
I love the electronic doodads on my 69 GTV!
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|06-14-2019 03:49 PM|
I think the engine ECU might be a tad more expensive and complex than the electronic dipstick. Heck probably the intermittent wipers are.
I suspect the trend to these devices as opposed to owner removable metal dipsticks has something to do with the planned federal regulation about maintenance free engines. Plus, no dipstick means one less potential airleak.
The trend is also to from the top oil and filter changes which work well with no dipstick tube.
|06-14-2019 09:46 AM|
You are putting a whole lot of faith in things which are manmade, thus susceptible to failure. It is a given.
Plus, the electronic dipstick system has to cost more than a straight metal stick with a couple of markings on it. Car manufacturers worry about costs of even very small changes, so I've read. I remember reading about Ford having to make a change in the Mustang firewall sheet metal years ago (unwanted vibration or something like that), and being upset that the fix cost $.50 per car.
|06-14-2019 06:49 AM|
I'm pretty sure engines with electronic oil level displays also allow manual checking of the oil level through an oil extraction tube, if absolutely necessary.
All such systems indicate to the driver either the correct oil level, a message saying the information is not available (usually with wording suggesting how to deal with that message) or a fault message advising the driver to have the system checked.
None of these features apply to a manual dipstick.
Not only do most drivers not check the oil level these days there really is no reason why they should need to.
|06-13-2019 08:00 PM|
|06-13-2019 06:08 PM|
We are ending up with many people who can make a computer do neat things, but don't know how to start a car, let alone drive it. The percentage of young people who do not even have licenses and don't care to drive is at an all time high. Either they let someone else do the work, or they just sit engrossed with the smart phones glued to their collective hands.
As for locking a car? Friend of mine said, why bother. It's a stick shift, and 95% of the people these days who are inclined to steal it can't drive it, lol.
|06-13-2019 05:54 PM|
"As other outlets have reported, this switchover is intentional. It started with a handful of European luxury marques (Audi, BMW and Porsche), and is gradually making its way downmarket. And it's happening by popular demand. Common wisdom holds that the dipstick is dying for cost reasons or environmental concerns, but neither of these theories are true. We're losing the dipstick, manufacturers claim, because most of us don't use it."
That's the reason right there, most people don't use them or even know they exist.
"Do a sensor and an oil-level gauge do the same thing? Of course. Still, the room for error is disconcerting. Sensors fail; computers have glitches; readouts aren't always correct. A certain intangible quality is missing, even if it isn't immediately apparent. "
Yup. Why I don't like not having one. Old school thinking since this motor may not burn a drop of oil but there is still something in the ability to check the oil manually. "MANUALLY".
|06-10-2019 11:12 AM|
The engine/drivetrain in my "old" 91 164S has run completely trouble free for tens of thousands of Kilometres (307,000 to be specific at this point). Heads never off, same "as new" oil pressure, no injector or ignition problems, no transmission issues (finally had to replace the clutch), no axle or hub problems. Yes, it sucks oil due to bad OE oil rings from new. Electric sensor (found on all cars) failures were sometimes issues, and inadequately sized OE steering rack, seals evidently overloaded, as well.
There is nothing special about an electronic dip stick, as the accuracy is not needed, ie, valueless in the real world, and the metal stick version cannot fail, so it is 100% reliable, and it's accuracy is clearly good enough.
Yes, some newer electronic drivetrain control systems do improve the performance and lower pollution, but much of the rest, as in the infotainment systems, are just changes because "it's new and different", nothing more. And, some of the new electronic systems for steering and braking, as examples, are hardly necessary, and actually distance the driver from much of the sensual input desired for better vehicle control. The technical word for that might be "numb". Will give you that with self driving cars, who the heck will care. Just get in and go to sleep, lol.
Friend of ours back east bought a new Camry to replace her old one. Spent well over an hour being lectured by the salesman about how wonderful the new infotainment and car control systems were compared to her old 2000 version, what all neat things they could do, most of which she decided she would never ever bother to use, too much to remember or figure out for functions meaningless to her and almost all other drivers. Just had to laugh at that.
|06-09-2019 07:22 PM|
The electronic dipstick (oil level monitor) also tells the driver when it isn't working.
The sender units in these systems are very reliable. In fact the number one reason current cars are so reliable is solid state electronics. Modern engines run completely trouble free for tens of thousands of kilometres because of modern electronics.
|06-08-2019 09:14 AM|
Electronic? Really, you know what I said, electric. And I do not believe that newer "electronic" versions would be any more reliable, being more complicated, with an accuracy which is not necessary in the real world.
The all too famous Porsche brand also used the same type of high silicon content linerless engines in several models. Just because GM couldn't get it right... however, yes, the Vegas was a huge joke on the automotive world. Haven't seen one in many years now. No one keeping one as a classic car, insured by maybe Hagerty, lol?
|06-07-2019 09:26 PM|
Electronic dipsticks show actual oil level including over filled. Overfilling is a very common fault caused by incorrect use of a dipstick and can destroy an engine.
Those Vega engines were ridiculous: cast iron head bolted to a liner less aluminum block....designed for self destruction.
|06-07-2019 07:53 PM|
I remember some older cars which would shut the engine off if the electric oil level sensor read low for one reason or another. Seem to remember one was an old Chrysler of some sort my boss had, and another was the infamous Vega, owned by a friend. They had steep driveways, and they could end up with an engine which would not start, being maybe a qt low. They didn't know about this function, and thought maybe they needed an engine rebuild, not being car people, lol.
Electric dip sticks are just not necessary in real life. If any engine is soo sensitive to oil level that misreading a mechanical dip stick by 1/4 qt or so makes or breaks the engine, I want absolutely nothing to do with it.
It's just "new product" foolishness.
|06-07-2019 07:32 PM|
Originally Posted by Michael Smith View Post
|06-07-2019 07:28 PM|
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