I have a friends car that Im working on for him. He has a 1999 Buick Park Avenue Ultra,6 Cylinder, 3.8L SFI SC OHV. He took it to Auto Zone to have them hook it up to see wI have a friends car that Im working on for him. He has a 1999 Buick Park Avenue Ultra,6 Cylinder, 3.8L SFI SC OHV. He took it to Auto Zone to have them hook it up to see why the engine light was on and it showed up as the "Related Parts" are Air Filter, Oxygen Sensor, Air Charge Temperature Sensor. And the "Related Items" are Mass Air Flow Sensor, Manuals and Software.
He bought a new Mass Air flow sensor and put it on.

I have 2 questions...

1. When he had me look at it two days ago we went for a five minute ride to the gas station and I checked the tire pressure and they were all around 5 pound different. I looked at the sticker that was on his trunk lid and it said to put in 30 pound in the front and rear. So I took air out of each tire to put them all at 30 pounds. I noticed that the first number on the tire was higher then what the recommended tire size is for his car. Does the first number on the tire mean how wide the tire is? I just wondered if the air pressure should still stay at 30 pounds.

2. He has been driving for the last week or so and noticed that after about 20 minutes of driving his temp gauge would skyrocket and most of the time the car would shut off untill it cooled down then it would start back up. So, after we got to the gas station after just a five minute ride the tope radiator hose that leads from the radiator to the thermostat was burning up and it was even hard to try to squeeze. His over flow was almost to the top. He told me that he has been adding the 50/50 mix to the over flow container cause he couldnt get the radiator cap off. So, he took the car to Auto Zone yesterday to hook up to see why the engine light was on and it showed what could be wrong (what I explained at the beginning of this comment). So he bought the Mass Air Flow Sensor and he installed it. I went over late last night after I got off work and had him start the car up and I was able to get the radiator cap off first which had some glue type fluid I wiped off from around the spring on the radiator cap. Also I looked in the over flow container and it was filled almost to the top. I had him turn on his heat full blast and after a couple minutes of running we noticed that there was antifreeze dripping under the car. It was hard to tell where it was leaking from sence it has a plastic piece that ran across the front of the car under neith and the fluid was coming from the corner of that plastic piece. I would of had to take off the air cleaner just to see the over flow tube sence it funs under it to the bottom of the over flow. I was gona do it today after I got up. I just called him and he took it to Apex and they hooked it up somehow to a pressure test and said that antifreeze started flying out of the over flow container. Apex tod them that the leak must of been from too much antifreeze in the over flow and he said the pressure test showed the raidiator cap was fine. And they sent him on his was.
Is it normal for the type of car he has to get that hot after just 5 minutes of driving? It has like 220,000 miles on it and he bought it in the past 6 months from a used car dealership, so im wondering if it would be a good idea to change the radiator cap sence it had the glue like substace on it when I wipped it off last night? And maybe even changing the antifreeze? And even after he changed the Mass Air Flow Sensor the top radiator hose still gets very hot..

First things first. Never check tire pressure hot. Always do it when the tires are cold. Be sure your checking the sticker on the drivers side door jam for tire inflation. I'm thinking your looking at the sticker for the compressed air ride suspension.

Second. Was his A/C running when you noticed the drips under the front of the car? If so, then more than likely it was just water coming out of the HVAC system. This is normal.

Third. A skyrocketing temp gauge tells me he has a sticking thermostat. And with a sticky goo under the radiator cap only tells me the cooling system is in dire need of a flush. Might as well repace the thermostat at the same time. Once that is done, grab a garden hose and spray directly into the radiator fins to clean it out.

x2 on everything mike said but i would get the rad cap too its cheap insurance like changing the thermostat when you got things apart and its got 220k

After 220k the radiator may be getting plugged with limescale, that would give similar symptoms to yours.
If it is furred up flushing probably won't do much good, a new/recored radiator is the answer in that case.

I tend to go on like a scratched record about radiators, in my defense I say replacing the radiator has cured a lot mystery overheating issues on a lot of cars over more years than I care to remember.

Roger.

ive had a bunch of old cars and never bought a rad unless it was leaking. if im having issues i take it out if the car and give the inside and fins outside a few good flushes with the hose, thats always taken care of it.