Buying a used car re: inspection

Factual Questions
1

I think this is FQ. If not, mods feel free to move it. These questions are based on videos I have seen and now my experience with my son’s car.

When buying a used car (and maybe this is a post-covid phenomenon) ISTM extremely important to pull the valve covers and look at the amount of sludge in the engine. I think me as a consumer could be fooled with a fresh oil change but maybe a mechanic wouldn’t be.

Question 1: Assuming a reputable car dealership (not buy here / pay here), whet is the process for getting the car to drive to your mechanic for an inspection? How long will they let you have the car?

Question 2: Beyond the price of a pre-buy inspection, how much more would it be for them to pull the valve covers and tell me what they say? Would the dealer even allow that?

Question 3: On a used car, would the dealership service department pull the valve cover so I can inspect it before I buy? What if it is, “I have the cash in my pocket and I’m buying it IF you show me no sludge.”?

2

How much is the car worth? Pulling the valve covers is not going to be cheap. You’re looking at probably $200-$400 for new gaskets, plus the labor.

This sounds like overkill to me for a typical used car, but it’s going to depend on what you suspect may be wrong with it,. Pulling a couple of plugs and inspecting them, doing a compression test and checking the oil at the bottom of the sump for metal are all good due-diligence practices to have a mechanic check. Also, if you don’t know what to look for have someone drive the car to check for hard shifts, differential noise, etc.

But unless I was buying an expensive collector car, I wouldn’t pull the valve covers unless I suspected something. An older used car probably isn’t worth it, and a newer one that IS worth it is probably new enough that you won’t find anything even if the car is being abused.

If it worries you, a good option is to buy a slightly used car still under warranty. Three year lease returns that still have two or more years of warranty on the drivetrain are a decent choice.

3

You tell them you’re not interested in the car unless your mechanic can inspect it. You make an appointment with your mechanic. You drive the car you are interested in to your mechanic, he inspects it, when he’s done he’ll give you his opinion, you pay him for his time, and you drive it back to the dealership.

Depends on the car. Usually not much but the mechanic can tell you exactly what it will cost with a phone call based on the make and model.

Of course they would as long as they already know it’s clean or have the time to clean it up before you see it.

4

Few dealerships will allow this. But they might give you a 72 hour or something return period. Maybe, if they are desperate for the sale, the test drive might include a brief stop at your mechanic.

But yeah, on a bought from the owner, not a dealer car, you can just meet at your mechanic. That’s what I did, and there was no issues.

5

If you think that you should pull the valve covers before buying the car, you should definately not buy the car.

Most people will have some maintenance records or receipts to show you. If not, what does the engine look like? You can’t really turn an abused engine into an apparently well maintained one just by cleaning the engine, although a shady dealer might.

Look for any signs of a leak. Pull the dipsticks for both the engine oil and auto transmission and look at them. Transmission fluid should be a clean red color, brown is bad. Remove the radiator cap and look at that fluid, it should be clean and either green of orange depending upon the model.

Check the belts and hoses. Are they cracked, old, or worn? Belts are often overlooked, if the car has resonably new looking belts and hoses, someone is taking care of things.

Check the brake fluid in the reservoir, is it clean and full? Tires in resonable condition for the miles?

There are many indicators of whether a car has been properly maintained. But unfortunatley a lot of the things that you should look at are now hidden under the plastic engine covers. The engine covers are there to purposely keep the average person from working on their own car maintenance. People will open the engine hood, take one look, and decide that they cannot work on this car, but once you remove all the plastic there is still a basic engine under there with spark plugs, wires, hoses, etc. The engine covers are there to keep you from seeing them.

If you have one, or know someone, with and OBD II code reader that is a big help. There is an OBD II port inder the dash, usually on the driver’s side, that you can plug the reader into. This will read the fault codes. You may find no fault codes and think, Yeah!, but that probably means that the seller has cleared and reset all the codes. No codes is not really a good sign for a used car.

Good luck. Car dealers excell at knowing all of these things.

6

Pulling valve covers isn’t a normal part of a PPE, and I unless it’s a model that had a particular problem with sludge I think it would be odd to insist on this. As Sam notes, the level of effort can range from “negligible” to “pain in the ass” depending on the model (pull the valve covers on a Subaru, it’s a gas). And depending on the age you’ll likely need or want to replace the gaskets at your expense.

You may be able to accomplish what you want with a boroscope through the oil fill hole, depending on the model.

7

I’ve done this a number of times. From small used car lots to major dealerships no one has objected. If they did I wouldn’t think of buying the car.

8

One more piece of used car advice. NEVER buy a used car from a dirt lot ‘Cash for Carz’ kind of place. They get the cars the dealerships won’t touch at auction, and they have no reputation to uphold. Sell enough lousy cars to develop a bad rep and you just close up shop and move to a new lot called “Best Used Cars” or whatever.

9

In a couple of minutes you could do a semi-decent job of this yourself, right there on the seller’s lot, by removing the oil filler cap and using an endoscope. Various models are available for use with a smartphone - prices start around $35.