Car troubles

[johnridley]

As I posted before, I finally took the Taurus in for service. They fixed the main issues but never found the flaky speedo problem the girls reported. So today T and I headed out to a few stores, and took the Taurus for the first road test since the repair.

Not good; about the time it was getting well and truly warm, it started to miss badly, and the check engine light started flashing. Flashing is bad. It's never flashed before. I know that means critical problem, but a quick look showed that I had oil pressure, and the engine was not overheating, and I was already at perihelion from home and about to start hitting stores on the way back. We went to Recycle Ann Arbor to unload a whole lot of packing peanuts. When we got there, there was smoke coming from the engine compartment. Smelled like rubber. It was coming from the serpentine belt area. We dumped off the recycling and I started heading for Chelsea to leave it at the dealers. We made it though it had very little power, it was missing badly and the engine light was flashing all the way.

There was no smoke coming from the engine when we got there, and it didn't even really smell that bad (at the recycle center, FOUR people came up to me and said "Um, you know your engine is smoking?" The woman in front of me said "That smells like serpentine belt burning up" which it did. Anyway, at this point I'm betting that the dealership put something back together wrong or incompletely and some hose (maybe EGR or something) burned through, causing massive crazy readings, extremely bad fuel mix, and the smell. Anyway, the thing is in the dealer lot. We're one up on cars anyway. Tuesday morning I'll bike to the dealer (they don't open until 7:30) and fill them in on the symptoms.

Comments

[madtechie2718.livejournal.com]

It is stories like this that make me dread the time when my ancient Toyota RAV4 dies and finally needs replacement.

It, like the majority of cars in the 1995 and earlier era does not have much in the way of electronics and general complexity between accelerator, engine and wheels, so to speak.

Apart from the odd clunking noise when reversing and turning (a known issue, I'm told) it still seems fine - the guy that maintains it tells me that at my paltry <1000 miles per year, it should last for quite a while - acts of malevolent deities permitting.

On the speedometer topic - it has long been the practice (as in about forever) for cars in the UK to have the speedo set to read a little high, so that an indicated 30 is around 28 and indicated 70 is an actual 67 or so.

Every UK car I've been in and used a GPS to check has been the same.

The last few times I've hired a car in the US, I happened to cross-check with GPS and found the indicated and GPS values to be the same. Does this imply that all the times I've hired cars in the US for the previous 15+ years I've been breaking the speed-limit in my UK-centric compensation for low-reading speedometers?

Oops!


I found a little info on this:

As with the UNECE regulation and the EC Directives, the speedometer must never show an indicated speed less than the actual speed. However it differs slightly from them in specifying that for all actual speeds between 25 mph and 70 mph (or the vehicles' maximum speed if it is lower that this), the indicated speed must not exceed 110% of the actual speed, plus 6.25 mph.

For example, if the vehicle is actually travelling at 50 mph, the speedometer must not show more than 61.25 mph or less than 50 mph. There is also the added problem of cars not complying with the United Nations standards, being imported and allowed to be registered, making the situation even more complicated.

[johnridley.livejournal.com]

Well, I suspect that whatever's wrong with this car, it's not serious. There wasn't much wrong with it before, just needed its EGR passages cleaned and a new O2 sensor. I'm betting it's just some little thing that seems big.

The speedo problem that was reported to me was that it was oscillating wildly. Probably a bad connection; it's an electronic speedo. AFAIK all modern cars use the vehicle speed sensor, feeding into the computer, and the speedo itself is a stepper motor of sorts; on the minivan I can actually see it moving in steps if I watch carefully (they're small steps). Therefore I think they're totally accurate (given what the computer knows about the tire diameter - I wonder if it's possible to calibrate that?).

The law in the US allows a +/-5% error. In the UK a 10% spread is also allowed but it's shifted; it may not read low at all.

In reality the modern speedos are dead accurate as far as I can tell. I clocked the one on the Taurus yesterday with a speedo and at 60 MPH it came out exactly right to the limit of my stopwatch and finger across one mile marker. I'll do it over several miles later.

[erikvolson.livejournal.com]

My Honda reads about 2MPH low when compared to a GPS.

[mbumby.livejournal.com]

My cars have always read high -- My last toy would be going about 65 when it was 70-indicated. My current Toy, though, reads DARNED close to the actual speed. When my GPS says I'm doing 70, the speedometer is still over a portion of the 70-line.

[johnridley.livejournal.com]

I don't think there's much excuse for inaccuracy anymore. Speedos used to be pretty crude mechanical things, but these days they are digital readouts. Even if it looks like a gauge, it's a digital gauge, and the computer knows exactly how fast you're going. The only source of inaccuracy is if the tire size is wrong. It would be nice if they allowed you to adjust that to get closer accuracy when you changed your tire size, but people would use it to cheat on their odometers.