i checked my tire pressure and they are 27 or 28 psi. since the tire placard says 29 psi, shall i inflate them immediately or is 27-28 just ok?

what tool(s) shall i use to inflate the tire? is there anything that can pump air and at the same time monitor the pressure (with reasonable price, of course)?

 

Go to a gas station and fill them. Fill them some, check the pressure and then add more or let some out as required.

Some of the sations in my area have machines that let you put in your target pressure and then they fill the tire to it and beep when they are done.

Be sure the tires are cold when you check the pressure. Cold means not driven in 4 hours or driven less than a mile or so to the gas station.

 

thanks, the dealer says every 10 degrees (Fahrenheit i guess) drop in temporature will deduce the pressure by 3 psi. thus explain why 1 week after maintenance the pressure is like now.

is this true?

 

I don't know about the numbers you quoted, but yes, it is true. Cold weather makes the PSI goes down as the air inside the tire gets smaller.

BTW, do yourself a favour and buy a good quality tire gauge. Even digital ones go on sale and can be bought cheaply now. Accutire is a good brand. I would never trust the thing on a gas station's hose.

 

I got a digital gauge from AutoZone for $4.99. It was supposed to be disposable, no replaceable battery. I've been using it for 5 years now.

 

How come sometimes you fill it to specs, but it still looks underinflated? And if it keeps losing air everyweek, is it most likely due to the rims>?

 

Looks mean nothing.

No. It's most likely due to a leak in the tire.

 

Usually a slow leak is the tire tread having a puncture or maybe the valve stem, but sometimes it can be the tire bead not sealing well against the wheel. Usually this would be due to rust though, which isn't as big an issue with the aluminum wheels most people here have.

Get a tire shop to check it out.

 

Bottom line is tires aren't "set it and forget it". The manuals state to check them "periodically". I check mine weekly.