Random Thoughts... [Automotive Edition]

This is going to sound horrible but maybe erm 2 years ago. It was in the shop for a massive stalling problem (left me stuck at a shopping mall for a while...) and had a load of other stuff done to it (new tires, something with the brakes, etc) when it was there, so perhaps it was done then.

If not, then the car hasn't had one in 4 years. I'm horrible I know.

Depends on how many miles are on it in that time and whether or not any parts are currently bad. You could also have a, or several vacum leaks.
 
EFI cars do not require tuneups every X years per se. Usually it's thousands of miles, and it's basically the 30K/60K, etc.,etc. service. Annual tuneups are a thing of the long dead past for most cars.

In the case of the Saturn, I suspect your coolant temperature sensor and/or oxygen sensor are going or have gone. Pretty common failures.
 
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But if his O2 sensor had failed, wouldn't it have triggered the Check Engine Light? Or is that only for OBDII (1996 and up) cars?
 
OBD-II has oxygen sensors installed in pairs (and so do some earlier systems) - one 'main' one and a second one to 'check' that the first (and the catalytic) is working properly. If you have two 'banks' (doesn't have to be actual physical banks) or exhaust pipes, you have four, two main, two check.

His only has one. The computer has NO idea whether the O2 sensor is working properly or not (unless there's a dead short or open circuit) and therefore cannot set a code. Same thing with the coolant temperature sensor, though that goes for most OBD-II cars as well - unless there's a second sensor, there's no way for the computer to know that the CTS reading is off if it hasn't shorted out or gone open circuit.
 
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But he is in PA, if his Oxygen sensor was shot he wouldn't have passed inspection.
 
But he is in PA, if his Oxygen sensor was shot he wouldn't have passed inspection.

According to the PA state website, 42 counties there don't have a smog inspection at all, so it would have passed the visual if he was in one of those.
 
Oh I see. I have a question about another thing you said.

So in OBD1 cars, i.e. my Volvo, there is no indication of the oxygen sensor being bad? Then when would the Check Engine Light turn on? For what reason, if not for A/F mixture?
 
The Check Engine light can come on for many reasons, doesn't have to be the A/F mixture. There's over 900 codes that an OBD-I Nissan can set (for example,) depending on model, so you need to get a code reader for Volvo and find out what the problem is.
 
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No, the check engine light is not ON. I was just assuming that if my O2 sensor fails it will light up. Apparently not...
 
Wash car - detail car - get bird shit on car - wash car - detail car - get rain - get sunshine.
 
EFI cars do not require tuneups every X years per se. Usually it's thousands of miles, and it's basically the 30K/60K, etc.,etc. service. Annual tuneups are a thing of the long dead past for most cars.

In the case of the Saturn, I suspect your coolant temperature sensor and/or oxygen sensor are going or have gone. Pretty common failures.

But if his O2 sensor had failed, wouldn't it have triggered the Check Engine Light? Or is that only for OBDII (1996 and up) cars?

Aha! I remember that when I bought the car, the seller (it was his daughters college car) said that the check engine light came on intermittently and he was able to read the code by placing a paper clip into the OBD port under the dash. He showed me how but that was like 4 years ago... He said it was a oxygen sensor but it was an easy fix. The mileage hasn't been this bad though, but i can imagine it deteoriating over time to the point where now in these conditions it's noticeable.

I suspect the light has blown out as of yesterday, as I didn't see it come on and off like it does on longer drives, usually when it comes on the transmission acts wonky, but not always.

Even more signs it's time to retire my plastic appliance I guess.
 
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No, the check engine light is not ON. I was just assuming that if my O2 sensor fails it will light up. Apparently not...

There are a few ways on O2 sensor can fail. As Spectre already said, there is the short and dead open that the computers can read. There is also what is known as a "lazy sensor" failure, the computer can't always see this as anything more than a need to adjust what the A/F mixture is and you need a scanner to diagnose it.
 
A quick calculation shows that my Mazda 626 uses 6,4-7 liters per 100 km. Not bad for a car that's closing in on 260k km.
 
If everything is working as it should, the amount of kilometeres/miles driven shouldn't have any effect on fuel consumption. Or power. Okay, at some point cylinders might start to lose compression and then it's the end, but it's a crappy engine if that happens way before half a million kilometers.
 
There are a few ways on O2 sensor can fail. As Spectre already said, there is the short and dead open that the computers can read. There is also what is known as a "lazy sensor" failure, the computer can't always see this as anything more than a need to adjust what the A/F mixture is and you need a scanner to diagnose it.

But considering the fact that the car is getting the same mileage as advertised when new (19/27), I can assume that the O2 sensor is fine for the moment, right?
 
But considering the fact that the car is getting the same mileage as advertised when new (19/27), I can assume that the O2 sensor is fine for the moment, right?

Probably, but they are wear items.

rick, I can't emphasize just how much you need to either sell the car immediately or figure out why the check engine light keeps coming on. If it's running as rich as you say, you may experience engine failure soon - the 1.9 is known to have issues with carbon buildup on the back of the valves if allowed to run rich for a significant period of time.

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Above is a generic example; eventually the buildup causes the valves not to close all the way. If you're lucky, the car just doesn't run. If you're unlucky, the next time the piston comes up it slams into the valve and that's all for the engine.

Either dump it now while it's running, or fix it. If you don't, you're about to not have a car either way.
 
My grandmother saw one of these today and said she liked it...

2011-Honda-Civic.jpg


This is a woman who can't drive and knows absolutely nothing about cars, let alone ever notices them.

And to think I thought Honda was doing a good job of scaring old people off.
 
You just have a awesome grandmother.
 
Got my data cable, sucessfully fiddled with my mates A3 yesterday, reprogrammed rear lights:

DSC00257.JPG

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Normally only the outer sections are on for driving & braking, inner is just foglights, now I changed it to the rear fog light being on dimmed with normal lights and doubling as a braking light. So much nicer. Tonight we try to enable the front foglight cornering light mode \o/
 
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How much did that cost you?

I need to find one for my GTI, there are a few things I absolutely want to have done.
 
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