Do you think testing is the most important process when it comes to car repair?

hoodedstranger77

$1.89 o-ring fixed my MIL problem after I spent hundreds by randomly replacing part after part. Learned my lesson.

Alright. Im an idiot. I bought a scan tool several months ago. Started tinkering on my car trying to get the code P0171 off. I changed O2 sensors, MAF sensor, EGR valve, PCV valve. Ended up smoke testing it with a cigar and hose. Found out the leak was coming from a connector on top of the manifold that runs from a vacuum line into the brake booster. To fix this problem it cost me $1.89 for an o-ring for the connector. And I spent a lot of flipping money trying to get code P0171 off. Not to even mention the questions I asked you on this site. Ive learned my lesson. Testing is the most important thing when it comes to car repair. Otherwise you can spend a butt load of money for stuff you dont even need. And having a scan tool is NOT a fool proof way of testing your car for problems. It just sort of gives you can idea about what could be causing the problem. I cant believe all I needed to fix my car was a stupid o-ring. I will say Im relieved though. And I hope my experience can help others. Only a fool learns from his own mistakes. The wise man learns from the mistakes of others - Someone obviously smarter than me.