Have we reached Peak Reliability for internal combustion engine cars? (camshaft sensor)

Our 10-year-old Infiniti has 80,000 miles on it. It recently went from “running perfectly” to “dead in the middle lane” on the Mass Pike (I-90). The transition occurred in about two seconds. The culprit turned out to be a bad “cam sensor” (Wikipedia article on a similar crankshaft sensor) that feeds the ignition timing system. The old-school distributor wasn’t perfect, but timing problems would result in a rough-running engine rather than an instantly dead engine, no?

Based on my experience with a 1998 Toyota Sienna that simply refused to break, I thought that we were on track for service-free and incident-free vehicles. But now I’m wondering if Peak Reliability wasn’t 10 or more years ago. Cars today have a lot of complexity and, apparently, potential for hard and sudden failures. At 8,000 miles and one year old, this particular Infiniti had an all-systems meltdown caused by some brake system controls. The latest cars have auto-braking, lane-keeping, and various other collision-avoidance systems that would seem to have the potential to disable the vehicle.

Readers; What do you think? Will cars actually be getting less reliable from now on? Except maybe electric cars that have a lot fewer moving parts (but Teslas aren’t good for reliability, are they?).

[Separately, I’m wondering why this Infiniti could be shut down by the failure of a single sensor. The camshaft is plenty long. Amazon sells camshaft sensors for as little as $13 as replacement parts ($172 at the dealer, plus $388 for installation). From this I infer that the factory cost of a sensor must be less than $1. Why wouldn’t Infiniti put in 2 or 3 of these and have the ignition computer pick the cleanest signal?]

Finally, if you’re in the market for a new car, don’t neglect politics. A wealthy Hillary-supporter on Facebook regarding the replacement of a beloved Volvo: “Trump anxiety is a factor in any spending even though the market has been kind to me.” (i.e., Trump has made him $1 million richer, but he is so anxious about the future that he is keeping his money in the market rather than cashing out $50,000 of gains to buy a fancy new car).


  1. Ed M.

    June 10, 2017 @ 12:49 pm


    Only now that it failed, do you even know the existence of the cam angle sensor. Would you have purchased a Lexus instead of this Infinity if the salesperson told you it had full sensor redundancy? Nope. Too expensive and unnecessary.

    Cars with distributors and points needed tune ups every 5000 miles, tires every 10K.

    Cars today require significantly less maintenance than old cars.

    Every time technology in cars improves someone out there complains that it frivolous and now there is more than can go wrong.

    I can hear it now, the complaints of guys in 1912 saying electric car starters were an unnecessary complication and will soon break.

    If I were a smarter person I would throw something in here about a cognitive bias, but alas I am a deplorable.


  2. G C

    June 10, 2017 @ 1:09 pm


    Recommending Toyota, if you want reliability. I’d also recommend avoiding luxury cars. Too many electronic gadgets to go wrong.

    Compared to gas, I think electric cars are bound to be more reliable. I am just waiting for the batteries to become cheaper. Note: this increased reliability applies to the drivetrain only, of course.

  3. philg

    June 10, 2017 @ 2:35 pm


    I did a quick search for “redundant cam sensor” and it looks as though GM was thinking about this in 2001: http://google.com/patents/US6588404

  4. boozedog

    June 10, 2017 @ 2:50 pm


    Your experience seems to jibe with Consumer Reports brand rankings: http://www.consumerreports.org/car-reliability/car-brands-reliability-how-they-stack-up/

    Interesting to see that Infiniti moved from #24(!) to #8 this year. Nissan hanging out at #13.

  5. Roger

    June 10, 2017 @ 3:16 pm


    It is going to get worse when your sensors move to the cloud. Your car will stop working because of some glitch in internet communications.

  6. jseliger

    June 10, 2017 @ 3:18 pm


    Readers; What do you think?

    Who cares what I think? More importantly, this list offers the least expensive cars to maintain. Toyota dominates the “least expensive” list, with the Prius being the least expensive of all.

    Hybrids in general last a long time because of ultra low engine wear. The battery does much of the work the engine does in a normal car.

  7. J. Peterson

    June 10, 2017 @ 3:26 pm


    Old-school distributors can fail suddenly too. I was driving down the freeway in my ’86 Civic when I suddenly noticed the tach drop straight to zero. A moment later, every indicator on the dash lit up. The distributor’s bearings had seized, and the shaft snapped off. Fortunately I was going downhill in a car with a clutch, so it wasn’t too hard to coast off the nearest exit. There I found another 20th-century anachronism: a pay phone.

  8. Smartest Woman on the Internet

    June 10, 2017 @ 4:59 pm


    Last month, all the dash lights illuminated, and have remained so, on my 2010 Honda Ridgeline. The dealer advises that it’s a bad ABS module, for $1200 installed. So, I’m now riding around with an illuminated dash and functioning brakes but no ABS.

  9. Sam

    June 11, 2017 @ 9:20 am


    Smartest Woman –
    According the Risk Compensation article in Wikipedia, you may be safer without ABS.

  10. Jackie

    June 11, 2017 @ 11:57 am


    1. Early autos often had redundant ignition systems – both a battery/generator driven coil system and a magneto (self-powered) system. That way if your main electrical system failed the engine would still run. Sometimes there would even be redundant spark plugs. However, as electrical systems became more reliable, they dropped the backup magnetos – it was just not worth the extra cost for the rare instances when it would be needed. Small planes often still retain this system because the consequences of engine failure are much worse. In a car, usually you can just coast to the side of the road.

    2. Electro-mechanical ignition systems had numerous failure modes, some of which were “graceful” (the car wouldn’t start or would gradually run poorer) and other of which weren’t (car would suddenly stall on the highway). But mainly they had lots and lots of failure points (one of which was actually called the “points”) so that any modern electronic system would experience orders of magnitude fewer failures. When I was a kid, whether or not your car would start (or stay running) on a cold, damp day was an iffy proposition. There were all sorts of tricks (ether “starting fluid”) sprayed into the carb, drying off the ignition wires and inside of the distributor, etc.) that we would use to raise odds. Cars with modern electronic ignition and fuel injection rarely fail to start.

    3. For the Japanese and German luxury makes especially, peak quality was some years ago (maybe circa 2000). In later years, they have increased profits or reduced the need to increase prices by cutting corners in places where it doesn’t show. Any engineered product is always going to be a compromise between cost and quality/reliability. You could make a car REALLY reliable by having 2 engines. As you say, the fact that the cars are increasingly complex makes it worse because there are systems to break that didn’t even used to exist – ABS, traction control, now radar systems for automatic braking, etc.

    4. In the old days, if you were the kind of cheap bastard who kept a car for as long as possible, eventually the engine or transmission would fail in some catastrophic way or else the body would rust thru to the point where the car was no longer structurally sound and that would be the end. A 10 year old car would be at the end of its useful lifespan with fist sized rust holes, burning oil, etc.

    But modern cars are much more reliable and have much better rust proofing (and have many more gadgets) so that they keep running but drive you nuts because the climate control system fails or there are annoying rattles or the power windows don’t work, etc. The car still runs but you wish it didn’t so you would have an excuse to buy a new one.

  11. Jackie

    June 11, 2017 @ 12:24 pm


    “Amazon sells camshaft sensors for as little as $13 as replacement parts ($172 at the dealer, plus $388 for installation)”

    This shows the importance of NEVER taking your car (esp. “luxury” car) to the dealer after the warranty expires. You need to find an independent mechanic who works on Japanese cars or even better specializes in Nissans. The engine in your Infiniti is also found in lesser Nissans where the owners are not willing to shell out $500 to replace a $13 cam sensor. When something like this breaks on one of my cars, I order the part off of the interweb and my local grease monkey puts hangs on there for $100 cash. Over time this adds up to a lot of $.

    The fact that there are so many aftermarket cam sensors available and for so cheap must mean that they are fairly common failure items. Humans have a lot of different design flaws but because cars of a given make and model are all clones of each other they all have identical failure modes. If your cam sensor broke at around the 10 year/80,000 mile mark, they ALL break somewhere around then on this particular engine.

  12. SuperMike

    June 11, 2017 @ 10:13 pm


    I think Jackie might be onto something.
    I had an old Saturn, and it had a crank position sensor fail (also in a very inconvenient way) and the cooling system give out around 150k. I took care of those and nothing ever went wrong with the drivetrain for another 100k miles. (despite the fact that I almost completely stopped maintaining it)
    There are failure modes where an electronic ignition, electronic fuel injection, electronic shifting car will run in a degraded mode (flashing engine lights, etc.) It just sounds like your failure wasn’t one of them.

  13. the other Donald

    June 11, 2017 @ 10:15 pm


    My pet peeve is marine outboards’ water pump impeller, another single-failure device that can both strand me at sea and destroy the engine. Instead of installing two and signalling for replacement when one fails, I am advised to replace it annually, regardless of operating time. For me, this probably quintuples the replacements.

  14. Adam

    June 11, 2017 @ 11:05 pm


    Engineer 1: We should install a redundant crankshaft sensor. It will improve fleet reliability by 0.7%

    Engineer 2: That’s a great idea. I’ve compiled a list of these 8 other sensors that also cause complete loss of vehicle power when they fail, we should make those redundant too.

    Engineering manager: This could be a good program, but we have to expand the scope beyond the sensor hardware team. These additional sensors are going to require more ECU input channels, new software to allow redundant operation, and wiring harness changes. All that will require new documentation, impact to supply chain, and we’ll need to kick off a training program to educate all of the dealer service techs on the implications for their diagnostics and repair.

    Accounting / legal / upper management: Your budget has been reallocated to the self driving car team. All engineering resources will refocus on cutting the cost of the current sensor by 50%.

  15. SuperMike

    June 12, 2017 @ 12:06 pm


    @adam: In this fantastic course: https://ocw.mit.edu/courses/aeronautics-and-astronautics/16-885j-aircraft-systems-engineering-fall-2005/ they have a portion where they discuss the design of the redundant systems on the space shuttle. The designers seem to regret some of their decisions, as they describe the redundant system themselves, and the systems to manage them, as the source of many problems during the life of the shuttle. (To paraphrase: Apollo had a guidance computer and a backup, if either didn’t work, they didn’t go, the shuttle had quad-redundant guidance and a complex system to manage any exceptions; they went from having 1.5 systems to worry about to having 5)

  16. anon

    June 12, 2017 @ 12:30 pm


    I have not yet be able to test limits of my regular Honda cars reliability with regular maintenance done. Same comes for GM track engines.

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