Dumbest thing you did to your car

[gf]

What's the dumbest thing you did to your car?
So far mine was a quick and dirty ballast resistor replacement. I had no knowledge of soldering wires so just duct taped the wiring down for the weekend. Several other mechanical projects later I was driving one day and the car just stopped. I panicked and couldn't think so called the RACT.  "What monkey did this?" The mechanic said.

[irvine]

On my last e36 M3 I cut the springs.....

ALLLLLLMOST done it to my w116 but saving for a proper air ride setup 

[rumb]

I  already posted this a few months ago, but mine was not properly torquing lug bolts and loosing wheel causing $9500 damage.

My daughter's audi I was trying to reattach the rearview mirror and hit it too hard and broke the windshield.

same car I replaced some parts on front of engine and didnt engage clip that holds hood release correctly.  It took me 2 months to figure our how to get a coat hanger into the corrrect spot and release the hood finally. Probably spent over 8 hours total.

[JasonP]

I did not secure my new oil return hose and the belt rubbed right through it on the highway. I made it home but the engine was practically drained.

[adamb]

Late last year I was selling my Mercedes SLK in order to get something a little more family friendly. A keen lady "bought" my car in eBay and was coming with partner to collect. I decided to be nice by giving the lovely car a good wash. As I was cleaning under the wiper arms my hand slipped and the wiper recoiled, the edge cracking the windscreen. It was a £75 insurance callout to replace the screen. The lady took the car unrepaired with a £100 discount. Phew!

[floyd111]

I  already posted this a few months ago, but mine was not properly torquing lug bolts and loosing wheel causing $9500 damage.

My daughter's audi I was trying to reattach the rearview mirror and hit it too hard and broke the windshield.

same car I replaced some parts on front of engine and didnt engage clip that holds hood release correctly.  It took me 2 months to figure our how to get a coat hanger into the corrrect spot and release the hood finally. Probably spent over 8 hours total.

Guess you better hold on to that day job!