Testing a used car for possible flaws.

Factual Questions
1

Is there any standarduzed list of things to check before buying a used vehicle? Some things might be required by the state, and others might need to be functional like turn indicators and brake lights.

Body damage should be apparent, and a failure to start might indicate starter/alternator/plug/fuel line issues, but is there an agreed upon list of criteria that one might be able to consult?

My Dad’s an aerospace engineer, and has logged more hours under a car than many people have lived for. However, even with him in my corner, a few things can be missed.

A few examples might be: hazard light functionality, trunk release, cruise control, lighter functionality. These don’t matter that much, but if they don’t work, down goes the value of the car.

“Sleeper” issues, that any mechanics may have seen would also be welcome.

The car I’m looking at, at the moment is a '96 Acura RL, if that helps. I’d like advice in general otherwise.

Thanks!

2
  1. You and your dad should select the car you like, and make a commitment to the owner “subject to inspecition”
  2. Get thee down to AA or a trusted mechanic for a pre-purchase inspection - they are used to it and will check pretty much everything relevant giving you a comprehensive report.
3

Body damage isn’t always apparent. I always go to the back end of the vehicle and look down the right side and then down the left side, paying close attention to the lines of the vehicle. You’d be amazed at how many used cars you can find that look fine, but have lines that don’t match on the left and right (indicates the thing has been whacked pretty good and repaired).

Other things I look for:

Open the radiator cap (when cool!) and look for signs of oil.

Pull out the dipstick and look for signs of things other than oil.

Look at the engine for signs of oil leaks. Also, of you see a really clean spot near any sort of fuel line it probably means that the fuel line or component was leaking. Gasoline will dissolve oil leaving a clean spot.

Check the tailpipe for excessive black soot buildup (indicates that the car is burning oil, which means the rings in the engine are probably shot).

Excessive smoke out the tailpipe is bad. Look for white smoke (antifreeze) or black smoke (oil).

Check under the front and rear bumper for signs of repair.

Listen for popping noises when turning (bad CV joints).

See how smooth the braking is. Warped or chewed rotors will pull excessively towards that side of the car.

If the vehicle is a stick, drive up a very steep hill and try to get the clutch to slip. Generally shift through all of the gears to make sure they all work properly.

If it’s an automatic, make sure it shifts smoothly under a variety of conditions.

Use your nose. If the car smells musty in any way, run, don’t walk, away from it. Chances are it has been in a flood and it’s going to cause you no end of grief.

Check the tires for signs of uneven wear. Tires that are worn more on the inside or outside at the very least indicate an alignment problem. There are also some more serious problems that will prevent a car from being properly aligned.

Check the heater and air conditioner. Make sure that when you turn it on defrost that the air comes out through the right holes.

While taking it for a test drive, make sure you run over some potholes or bumps. You are looking for signs of something wrong in the suspension.

A lot of mechanics will take a look at a car for a reasonable fee. Having an experienced mechanic take a look at it is a good idea if you don’t have a lot of mechanical knowledge, or even if you do have a lot of mechanical knowledge and just want a second opinion.

4

The items you list are pretty benign. On a 15 year old car some things I’d check:

Put the car on a lift and check front and rear suspension. Ball joints, tie rod, bushings, wheel bearings. While it’s on the lift check engine, transmission and steering rack for fluid leaks. Carefully inspect radiator and water pump for leaks.

Have someone start the engine cold while you look at the tail pipe. Any blue puff of smoke at startup?

Look at the oil (dipstick). A milkshake look means coolant is getting in the oil. Brand new oil is suspect too (might try and hide the milkshake).

The test drive is important. Ask if you can do it without the seller. If the seller insists on riding with you, ask them not to talk. Listen for noises, turn radio off. Turn tightly at low speed and give it some gas. Any clacking noise (CV joints going out, $$$). How does it shift? Manual: where does the clutch grab, does it go into all gear easily? Auto: Any jerking between gear? Slipping? Slow shifts?

There’s more, but this should get you started. Also look for forums specfically for this car and look for common faults on this model.

5

Specifically for the Honda/Acuras, ask for the receipt showing when the timing belt was last changed. The water pump should have been replaced at the same time. If they can’t provide one, figure $600 for doing it immediately. Usually they are done every 60-70K miles and if the belt goes, the engine is toast. Also check the struts and all the electrical switches.

6

Buy or rent a ODB code reader. Restart the car and drive it around with it plugged in to see if it trips any codes.

Frankly, the DIY approach here may not be the best idea. Most mechanics will look at used cards for a small fee. In the long run youre better off with a professional opinion for 50 bucks than trying to guess it yourself.

7

Well I bought the car, and so far the only thing I’ve found even remotely wrong is the power side view mirror switch may not be working.

The seller did say that I might want to check the timing belt soon, as MikeG mentioned, and I’d HATE to have to go through another water pump issue again. Oh and he said that some emissions sensor may need to be replaced, not sure about how important that is, especially since my state doesn’t emissions test.

The tranny, brakes, and CV joints seem to be acting fine. I might need new shocks in the rear, but for now I’m fine with it.

Overall, very good advice here. Anyone know if silica gel can remove condensation from indicator housings?

8

Even if your Dad might be more qualified than some mechanics, if this car is going to be a big investment for you, you should still take it to a mechanic for a pre-purchase inspection. A really thorough pre-purchase inspection should include a compression check which, while not super difficult, is something that a prospective seller shouldn’t let just any old tire-kicker do. There’s also the issue of what happens if your break something while inspecting it-- no big deal if it happens to a mechanic but it could be some big trouble if it’s just you DIY-ing. Plus being able to put the car on a lift is pretty key for inspection of some suspension components, and can make finding other problems much easier. If this isn’t just some impulse purchase, spend the money to get an inspection.

As for the timing belt, there’s nothing to check. There is no outward way to tell the condition of one-- I’ve changed several that looked fine in place but easily snapped in half when removed. If the seller doesn’t have a record of the belt being changed within the service recommendation, plan on having it done as soon as you buy (if this belt snaps, your engine is ruined).

9

So if the timing belt snaps, the engine is destroyed?

What?

10

Destroyed? No. Damaged? Yes.

Some engines, including the one in your Acura, are interference engines. This means that if the crankshaft and camshaft(s) get out of synchronization – which is what happens when the timing belt breaks – then the pistons can (read: will) hit the valves and bend them. With bent valves, the engine will run poorly if at all. The cure for this is a valve job, which for most cars will easily cost 1000 or more.

An ounce of prevention is worth a pound of cure. Replace the timing belt when called for in the maintenance schedule. For your engine, it’s every 105,000 miles.

Back to the OP question, there are two things to do. The first is to operate everything during a lookover and test drive. Open and close all the windows, turn on the wipers and washers, use the cruise control, lock and unlock the doors, use the radio, etc., etc. Anything a driver might normally use or control should be put through its paces.

The second thing is to take it to a mechanic/shop for a used-car inspection. I’m not going to list all the items that should be checked because it’s tedious (to list them) and a good shop is going to know what to do. A do-it-yourselfer qualified to properly inspect them will likewise know what to check.

11

I don’t think our auto shop had ever had an interference engine in with a broken timing belt that didn’t require a new engine. The problem usually is that the valve stems are so badly bent that they are essentially permanently welded into the valve guides and can’t be extracted, and the engine is therefore toast. Often it doesn’t do the pistons any good either.

The morale is don’t ever let your timing belt break if you’re driving around with an interference engine.

12

That surprises me because I’ve been in the field for 35 years and never seen that happen. Also, I would think that even with valve guide replacement the cost would be less to repair the engine than to replace it.

That advice I absolutely agree with.

13

Often a rebuilt engine, with a reasonable warranty, is available for less than the price of all the repair necessary to rehabilitate the damaged one.

BTW, I thoroughly agree with taking a potential purchase into a reliable shop for a pre-purchase inspection.

I’ll check with our records and see exactly how many of these things we get in during an average year. If memory serves, it is not a trivial number.

As a bit of an aside, this push towards ultra efficient cars, extremely minimal pollution, ultra safety and so forth is, I agree, ultimately a good thing for everyone. However, this generally guarantees that any significant repairs will be hugely expensive. I go out on the shop floor now and again, and look at some of the repairs being done and am amazed at the ability of our technicians to make any sense out of what they see. Your good auto tech doesn’t make anywhere the salary that should be paid for what he has to know and be able to do. Did you know that these techs have to provide their own tools (excepting the big stuff like lifts, computer analyzers, etc.), and typically have 20 to 40 thousand bucks invested in these?

14

I had a Honda Civic where the timing belt went with 105,000km and 5 yrs 3 months. The warranty was for 100,000km 5 years. They never mentioned that it needed replacing in the 5 years I had the dealer service it. I did not realize until much later they had been stupid (and me!). I just blamed cold Canadian winters. I traded it in, but AFAIK it need a head job because some valves were bent. These are teh same bozos who had a Civic motor on the bench; they mechanic demonstrated to a friend of mine how easily the engine tuned, turning the crankshaft by hand. No timing belt connected. Apparently they then needed to repair/replace the valves. I think this place stopped selling Hondas not long after…

The other thing that likes to fail are the CV boots. Once they crack open, which is more likely in cold winter areas, road dirt gets into the CV joint and it’s an expensive repair. When you begin to see extrior cracks, get the rubber boots replaced asap. Saves a much more expensive CV replacement.

Oh, and see fi they came close to replacing the oil once in a while. A friend bought a Honda CRX only to find that iot had the factory oil 3 years later. He had that changed, with no problems - but didn’t give him the warm and fuzzy feeling.

15

You’ve bought the car, so it’s moot, but one thing that is or was required in California is that the seller must make sure that the car passes smog. This came up with a used car that I was considering buying a while back. I took it to a mechanic who told me that it would not pass smog as there was something expensive wrong with one of the cylinders. I reported this to the seller who kept repeating some variation of “we just want to sell it. We’re interested in finding someone who is serious.” in response to my “You are legally obligated to make sure this works. If you sell it to anyone in this condition they will have grounds to sue you and they will win.” We went a couple of rounds with this. I’m not sure what was going through the seller’s hypothetical brain, but I did not wind up buying the car.

16

Just checked with the shop owner. On average, we will get half a dozen or so cars annually with interference engines that have broken the timing belt. Not always do they need a full engine replacement - sometimes just new heads, valve guides, etc. If it occures at freeway speeds, though, you could be in trouble. Either way, it’s either expensive, or really expensive.

17

Duly noted, and thanks for the heads up!

Looks like my brother, my Dad and I will be replacing that belt toot sweet. Thankfully the rear shocks aren’t too pricey either, and it looks like the EGR valve or oxygen sensor might be cheap too.

Would replacing the water pump at the same time make sense? My Dad said something about changing other timing related things while the belt was off, and another guy grouped the belt and water pump replacement into one “procedure”. I don’t know if they’re related at all or not, but I know that water pumps going out can be a nightmare.

18

Add in my 42 years and I have never seen this either. Also I used to travel the country as an instructor and I never heard of it in my travels.
I do see broken belts on a fairly regular basis in my shop. New Valves and away they go. Costs a pretty penny, but away they go.

19

Yes, I’d replace it. Some shops insist on doing it with the timing belt, and for good reason.

On many engines (including yours), the water pump is run by the timing belt. If the pump shows signs of leakage or roughness, it would be foolish not to replace it. Even if it seems okay, it’s unlikely to last till the next timing belt replacement, and replacing it separately later means re-doing all the timing belt labor to get to it. In a worst case the pump could lock up and damage the timing belt, possibly having the same effect as the belt breaking.

On other designs the water pump is run by a drive belt (can’t damage the timing belt), but is obscured behind the timing belt which has to come off to get to it. Here it’s worth considering the long-term savings of not repeating the timing belt removal. And then there are some designs where the water pump can be replaced without removing the timing belt, in which case there’s really little or no advantage in replacing them at the same time.

Another thing to consider is replacing the front engine oil seals (crankshaft, camshaft, and sometimes auxiliary shaft or oil pump). These seals are only accessible once the timing belt has been removed. Thus, most of the labor to replace them is already done. If the seals are leaking, it would be wise to replace them while the timing belt is off. Even if they’re not leaking, it’s good preventive maintenance to replace them as the odds are they will start leaking before the next timing belt is due. If they get to leaking significant amounts of oil, it could contaminate the timing belt and shorten its life. Replacing those seals can sometimes be a significant challenge, however, and is best done by someone with the requisite expertise and tools.

And of course the drive belts will be removed in getting to the timing belt, so this is the most economical time to replace them.

Note that your engine has a balance shaft belt as well as a timing belt. Replace them both. Make sure you have good instructions, or someone very experienced in this design, as it’s not hard to make a misstep.

On Hondas, and I assume Acuras, the crankshaft pulley bolt is usually REALLY REALLY REALLY TIGHT. You’ll probably need the special tool to hold the pulley or an acetylene torch to heat the pulley bolt.

I mean frickin’ TIGHT.