On my commute this morning there was a steel object on the freeway that was about the thickness of rebar and bent in a 3D S-shape like a ninja floor spike so that no matter what, a point is always up; about 4-5" across in any direction. I swerved to avoid it, but I didn't have enough time to see if the other lanes were free to swerve into those lanes, and I wound up running over it. It slammed against the underside of my car and in my rearview I could see it had bounced out almost 10' in the air and the van behind me had to swerve to avoid having it embed in their windshield. I watched my tire pressure sensor and gauges but they didn't change. I was really surprised that I didn't blow a tire - I'm now sold on Nitto NT555s. However, about 5 minutes later, my A/C stopped working - not completely, but it had lost maybe 80% of it's cooling capability. I got to work okay, when I left tonight I looked underneath and there wasn't any sign of leaking fluids or low tire pressure, but the car didn't start. The force of the object was enough to knock the cable loose from the positive terminal of my battery. I put it back on and all was well except the A/C was in the same state. I know very little about A/C systems on autos, does anyone have a suggestion about where to look first for damage? The object was run over by my right front tire, and I don't think the back tire hit it. What's in the A/C system is over on the passenger side that would have been most likely to have gotten knocked loose?

 

If it knocked your positive battery terminal off, I'd check the AC Condenser for obvious damage first. It can be easily seen from the front of the car through the grille or opening above the front lip.

 

^^+1

 

hmm ...

ninja floor spike on floor + knock the battery terminal off = wtf ?

hmm ...

ANYWAY, yes you should first check and see where did the ninja floor spike go.

Also make sure it did NOT touch any of your belts. cuz if it touches ur belt, a minor crack might result and when a belt breaks, it usually will take something with it in the process, like cut the coolant hose next to it or even worst cut other belts AND cut your battery wires. not good.

and its pretty easy to check A/C leak, visual inspection first, just to see if u see a big hole

IF you cant see any hole, and you wanna do it urself follow this to check A/C leaks:

Buy 2 bottles of R134a with UV dye, better get one with a mini-gauge on it, Autozone sells them. Get their reward cards program if you dont have one. You're going to need a lot of parts from them might as well.
Take the first bottle out, connect the gauge to the LOW side of the A/C lines
If you see Zero Pressure, Your system's R134a is all gone.
IF you see "some" pressure, you probably have a small and slow leak.
Anyway, Now go get yourself a cup or a bowl of warm water, the reason is that when you "start feeding" your R134a into the system, it gets cold and stuff inside might "Freeze", the warm water is there to "make sure it keeps flowing". So a bowl of warm water, put the R134a can in the middle of it. Turn the **** to on, u will see pressure moving at the gauge. let it run for maybe 10-20 seconds then go in and turn your car & AC on.
Leave your A/C on for maybe a minute or so, so it cycles the UV dye.
Turn it off.
Now go get the strongest flash light you can find, get a piece of paper and paint it light purple, put it over your flash light and start looking for the leaks.
When you find it, buy the right part and "fix" it. keep repeating the process until you're sure u get no leak(at least leaks that you can't see by UV dye, it can happen, trust me)
What u need next is a set of A/C gauge, and a 2 Stage Vacuum Pump.
A/C gauge u can get them from Autozone for cheap (like 50 bux) and The cheapest 2 stage vacuum pump came from Habor Frieght. but I believe in Quality more, so I got a set of Mastercool gauge, and a RobinAir 2 Stage Vacuum Pump.
use a pen to let all R134a out from the system. You dont want them to get into your Vacuum Pump oil.
Put the A/C Gauge on, you do NOT need to connect it to the high side, high side is used only to check if there is any blockage in the system.
Connect The Vacuum pump to the Middle of the gauge.
Turn the vacuum pump on, open the pump's valve, and turn the LOW side **** on.
You SHOULD see the pump vacuum goes negative, make sure you can pull at or above 28^mg or above (29 is best)
Turn the Low side **** to close and shut the vacuum pump off.

Wait for maybe 45 minutes to see if any pressure drops.

if it stays that way, your system has no leaks.

if it drops after a while, you still have a leak somewhere, keep checking until you find it (painful process)

if it stays, Turn the Vacuum pump on again and turn Low side **** on and let it run for at LEAST 30 minutes.

when its done, shut the Low side and Shut the pump.

I forgot our 8's R134a capacity, buy the correct amount of R134a, you can also buy one with maybe 2oz of PAG oil. cuz when you do a leak test, You will lose some A/C oil. and there is no way to find out how much oil u got left in there. so 2oz is a good guess.

Connect the 134a to the A/C gauge, open the hose at the gauge slowly to bleed the air out from the hose, when u see R134a coming out from the connector, secure it again

Now, Turn the Low side **** on, and go jump into your car and start the A/C, wait maybe 10 minutes the bottle should be empty (remember to put the can into a bowl of warm water)

keep repeating until you are done.
do NOT use those "stop leak" ****, it will leak again so why bother.

 

You should probably contact your insurance company (presuming you have comprehensive) prior to attempting to repair this yourself- you may be covered.

By the way, such an item is properly called a "Caltrop".

Bummer.

 

Apparently nycgps hasn't been taking his meds again