Will a valve job increas MPG?

I have a 1991 Toyota Celica GT with 220,000 on it. Will a valve job improve gas milage? I currently get about 22 mpg city driving if I use medium grade gas.



The reason I ask is that I was thinking of getting a new car - but a valve job would be a lot less$$$ and I just can’t see buying a new car that get less gas milage.

Nope, not unless you have valve problems.

Valve jobs are done to corect some type of problem with the valve train. Forgetting that for just a moment,look at the cost of the valve job and figure out how much better milage you would have to get to simply pay for the valve job, not even thinking of realizing a benifit yet.

“The reason I ask is that I was thinking of getting a new car - but a valve job would be a lot less$$$ and I just can’t see buying a new car that get less gas milage.”

Then buy a car that gets more gas mileage… : )

If your car is running fine, save money for a new car until this one has problems - then buy a new one. A new car will be much safer and efficient and it will have a future.

I was going to explain what a “valve job” actually is, but instead let me just say that if your engine is operating properly it means that your valves are seating (sealing) properly and there’s absolutely nothing in a valve job that would help gas mileage. Valve jobs are only to correct valve problems. They cannot improve mileage on a properly operating engine.

You run into a sticky area here with 220k miles on the engine. A compression test, both wet and dry, will reveal if a valve job is needed or not.

The sticky part comes into this when you have a valve job done, if needed, and the possibility of increased blow-by past the piston rings begins.

I’d advise against it unless the engine runs poorly and idles rough. You would be better off to make sure the tire pressure is correct, perform a thorough tune-up, and possibly advance the ignition timing a couple of degrees.
The caveat with the last one would be that there should be no pinging on acceleration.

Thanks for the quick replies everyone. The car idles ok and there is some tapping — but again there is 220,000 miles on it.

Thanks again for the input.

The short answer is “no”. Unless you have a burnt or bent valve that is causing a significant misfire, you will not see any increase in gas mileage. Your best bet at this point is to start saving money for a replacement car and keep driving this one as is until something serious breaks. Then, if you don’t want to spend the money to fix the car, you have a good reserve of money to replace your current car (down payment or outright purchase, depending on how long the Celica holds out).

Some Toyota engines say “adjust valves as needed”…If yours is one of those, perhaps a valve ADJUSTMENT is in order…The tapping should stop but no increase in gas mileage…

1991…220K miles…I would not “invest” any serious money in this car…

Sounds like a valve job is not the action to take. However I really like this car and it does get decent gas milage. The other thing I like about this car (other than the body style) is that mine is the GT hatchback…which means that with the back seats down I can put 8 foot boards in the back easily (I do woodworking as a hobby). Plus, the body and interior are both in very good condition.

Hhhmmm… Maybe a new paint job (which it desperately need) and drive it for a couple more years.

I do have a car savings acct ( like an Xmas club acct) as others have suggested in place.