There is no sure fire way to tell. But you can check yourself, or if you have NO idea what to look for, you could take it to a mechanic, offer him $25 or $50 to look and see if he can tell.
The best they could do is look to see if the bolts look like they've been turned or if the factory paint mark has been removed (they - the Toyota factory - mark key bolts with a bright paint so the dealership can tell if the bolts have been removed or messed with, should someone come in complaining). The problem with this approach is that you are telling them that you have no idea what to look for, and that a bad mechanic will tell you to get it replaced, even though you don't need one. You are putting yourself at their mercy... so go to someone you trust.
If it were me... or my daughter here are the options I'd consider:
1. Do nothing. Odds are, the belt was changed before you got it. If not, I wouldn't worry too much because this is a non-interference engine - meaning - the belt can break and there should be no engine damage ( 4 cylinder right?) If you are strapped for cash - this is what I'd do. And change the belt when you get to 170,000 miles for peace of mind... or sell the car at 170,000.
If it breaks on you, the worst case is you'll be stranded, have to pay an extra $100 or so for a tow, and be inconvenienced. Odds are slim though. The original belt would probably not make it 120,000 miles. So it was probably replaced somewhere between 60k (recommended for early) and 100k (90k is the recommendation but you can push these to 100 or 110 and not notice). So if you play the odds, it should last at least to 150,000 up to 200,000. Again - probably be ok to drive it to 170,000.
2. Call your mechanic (do this at a good mechanic - you will pay a lot more at a dealer) and ask how much it will be for a timing belt, water pump, spark plugs and wires. All of that will run somewhere around $500-$800... I would think more than $800 for that and you should find a new mechanic. Call a dealership and ask them the same thing, whatever price they give should be the highest price you hear.
Let's say $800. Start putting away $20 a week if you can, or at least $30 a month. Preferably $100. If you're only able to save a little, and you drive 15000 miles a year, in two years you'll have enough saved, and at 150,000 miles it would be a good time to do all the stuff I mentioned above. If you can save $100 a month, you can get it done in the spring.
3. If you can afford $500 or so now - and if being stranded by your car and having to go through the inconvenience of a tow really REALLY bugs you - get it done. No harm in extra maintenance, except the harm to your wallet.
If I thought the car was well taken care of, I would do option 2. Is the interior in great shape or was it abused? If it's a well kept car, just drive it, enjoy it - save $100 a month for repairs and such. If the belt breaks, it's not going to destroy this engine. Some engines are "interference" and some are "non-interference". If you have a 4 cylinder (and I think the 6 cylinder is non-interference too). you will not damage the car if the timing belt breaks. Non-interference means the valves will not be crushed by the pistons, even if they are in a fully open position, and the cylinder is at top dead center. If you have NO idea what I"m talking about, sum it up to say - aside from the inconvenience, there should be no damage to you or your car. When a timing belt breaks, the engine will just stop running. You'll try to start it - it won't. You'll have to have it towed.
I would drive it. Save up the money and replace it at 160,000 or 170,000 (even if I had a pile of cash - I would not get a new belt until 150,000 miles at the earliest).
If you think the car was NOT well taken care of, then they probably didn't change the timing belt. If you can afford it - go for it. It might be a waste of money, but the only way to know is if you keep driving it until 150,000 or so miles. If you make it that far - then they probably replaced it.
My dad had a Chrysler - 1987. He put 200,000 miles on it - he thought it had a timing chain. It had a belt. That belt lasted 200,000 miles. It broke - he got towed - got the belt replaced ($420 back in 1995) and then drove the car another 100,000 miles.
So there's no telling. Odds are - the belt will last you to at least 150,000.
Good luck
The best they could do is look to see if the bolts look like they've been turned or if the factory paint mark has been removed (they - the Toyota factory - mark key bolts with a bright paint so the dealership can tell if the bolts have been removed or messed with, should someone come in complaining). The problem with this approach is that you are telling them that you have no idea what to look for, and that a bad mechanic will tell you to get it replaced, even though you don't need one. You are putting yourself at their mercy... so go to someone you trust.
If it were me... or my daughter here are the options I'd consider:
1. Do nothing. Odds are, the belt was changed before you got it. If not, I wouldn't worry too much because this is a non-interference engine - meaning - the belt can break and there should be no engine damage ( 4 cylinder right?) If you are strapped for cash - this is what I'd do. And change the belt when you get to 170,000 miles for peace of mind... or sell the car at 170,000.
If it breaks on you, the worst case is you'll be stranded, have to pay an extra $100 or so for a tow, and be inconvenienced. Odds are slim though. The original belt would probably not make it 120,000 miles. So it was probably replaced somewhere between 60k (recommended for early) and 100k (90k is the recommendation but you can push these to 100 or 110 and not notice). So if you play the odds, it should last at least to 150,000 up to 200,000. Again - probably be ok to drive it to 170,000.
2. Call your mechanic (do this at a good mechanic - you will pay a lot more at a dealer) and ask how much it will be for a timing belt, water pump, spark plugs and wires. All of that will run somewhere around $500-$800... I would think more than $800 for that and you should find a new mechanic. Call a dealership and ask them the same thing, whatever price they give should be the highest price you hear.
Let's say $800. Start putting away $20 a week if you can, or at least $30 a month. Preferably $100. If you're only able to save a little, and you drive 15000 miles a year, in two years you'll have enough saved, and at 150,000 miles it would be a good time to do all the stuff I mentioned above. If you can save $100 a month, you can get it done in the spring.
3. If you can afford $500 or so now - and if being stranded by your car and having to go through the inconvenience of a tow really REALLY bugs you - get it done. No harm in extra maintenance, except the harm to your wallet.
If I thought the car was well taken care of, I would do option 2. Is the interior in great shape or was it abused? If it's a well kept car, just drive it, enjoy it - save $100 a month for repairs and such. If the belt breaks, it's not going to destroy this engine. Some engines are "interference" and some are "non-interference". If you have a 4 cylinder (and I think the 6 cylinder is non-interference too). you will not damage the car if the timing belt breaks. Non-interference means the valves will not be crushed by the pistons, even if they are in a fully open position, and the cylinder is at top dead center. If you have NO idea what I"m talking about, sum it up to say - aside from the inconvenience, there should be no damage to you or your car. When a timing belt breaks, the engine will just stop running. You'll try to start it - it won't. You'll have to have it towed.
I would drive it. Save up the money and replace it at 160,000 or 170,000 (even if I had a pile of cash - I would not get a new belt until 150,000 miles at the earliest).
If you think the car was NOT well taken care of, then they probably didn't change the timing belt. If you can afford it - go for it. It might be a waste of money, but the only way to know is if you keep driving it until 150,000 or so miles. If you make it that far - then they probably replaced it.
My dad had a Chrysler - 1987. He put 200,000 miles on it - he thought it had a timing chain. It had a belt. That belt lasted 200,000 miles. It broke - he got towed - got the belt replaced ($420 back in 1995) and then drove the car another 100,000 miles.
So there's no telling. Odds are - the belt will last you to at least 150,000.
Good luck