Intake gasket repair necessary? 1998 Nissan Altima

Hey everyone,

My Check Engine light has been coming off and on for a month. I finally took the car to the repair shop and was told it was the intake gasket. It will cost $600 bucks to fix. I am planning on buying a car some time next year, probably within the next six months. I really do not want to put money into fixing an old car.

So what does this gasket do and is it absolutely necessary to fix? The car is not running rough…at least not yet.

Ask the shop you took it to for the actual diagnostic codes associated with the check engine light (format: P0123) and post those codes here. Also ask how they verified an intake manifold problem.

If it is the intake gasket BUT the car is running fine then you might be able to just keep going (as long as it is running fine). BUT - one way that an intake manifold can leak involves having coolant getting into the engine and mixing with the oil. IF that is happening then you are not likely to make it 6 mos. Get the full story from the shop and post it. Pull you oil cap and your dipstick and look for signs that the oil is contaminated by coolant/water (brown, milky appearance to the oil).

Don’t bother if your are dumping the car.

The gasket’s main purpose is to seal the surfaces between the cylinder head and the intake manifold to prevent air from leaking in and coolant from leaking into the air passages or out of the car. Some cars have had a history of problems with his gasket, but your car is not one of them.

The code is most likely for a vacuum leak detected. With the age of the car, I’d check the condition of the vacuum lines before condemning the intake manifold gasket. The diagnosis you got would greatly depend on what they checked. If the car is running fine, I have my doubts about the intake gasket. A bad and leaking gasket would cause driveability or idle problems.

Until the car starts running bad, and since your trading it in soon, I’d ignore it.

The code is P0171


I don’t know how they verified it. Car has 140k miles by the way. How much would it cost to check the vaccuum lines?

You might have a look at these so that you understand a bit of what is going on with the codes:

You really do want to have the shop explain exactly what they did to verify the intake manifold leak since, as you will see, the list of possible problems is long. You might use it as a check list: “Did you check…, and what about…?” etc. If the car seems to be running fine, then I’d be very suspicious of the intake manifold diagnosis.

With just the most basic of mechanical skill you could pretty easily clean your own mass airflow (MAF) sensor. All you’d likely need is a screwdriver and a can of MAF sensor cleaner. (Might do no good, but as long as you don’t damage it, can’t hurt). Some of the rest of the stuff can also be checked without too much trouble.