Sorry this is a long read but boy was it a scary Friday night! My motor got hydrolocked but I was able to save it. Here how it happenend first, I installed a water/meth injection kit on it two weeks ago. In this kit instead of a electrical solenoid valve I used a check valve. Thing is this was a temporary check valve since it was off a chemical pump and was made of pvc and used a spring and ball system. Seems like the seat the ball rested against got messed up or deformed and the ball didnt seal well. So, overnight it seems the water that was in the windshield washer resovoir leaked into the intake since the intake is in a lower spot. Not knowing this I went to start the car Friday night and it turned over once before stopping violently. I was like wtf? I turned the key one more time and all the lights woud go out (from starter not being able to turn). I popped my hood to see what happened and when all looked fine at first I got the a bad feeling so I checked the windshield washer fluid tank and it was empty. Holy crap my heart sank. I took the intake off and I put my hand in through the throttle body and it was full of water. I unplugged the coils, took out the fuel pump fuse, removed all the spark plugs and turned the engine...it spat out a bunch of water. I removed the throttle body and looked inside and it was holding a good half gallon of water. I stuck rags in the intake and dried up all the water. I cranked the motor over a couple more times to make sure all water was out. After that I started to put everything back together and pray I hadnt broken any parts or bent a rod. When I went to start her up she came back to life purring like if nothing happened. What a relief! No noises, no vibrations and no blow-by. The motor has less than 10,000mi and is a forged bottom end so it looks like the starter didnt have enough force to bend or break anything so Im lucky it happened at startup instead of while running. I did an oil change to be safe a drove her around yesterday, so far so good. Scared the living crap out of me though. I saw my wife telling me we didnt have anymore money for the car, LOL. NOOO!

 

I hydrolocked my 2003 C5 in 2005 while driving in a sudden massive downpour here in Houston. I have a Breathless Performance Vortex CAI which sucked up the water when I hit a low spot at an intersection.

Dealer picked up the car, pulled the plugs, spun the motor, changed fluids(twice), and the motor seemed fine. The throttle position sensor had to be disassembled later and cleaned but I have since put an additional 60K miles on the motor with no issues.

Good luck, sounds like you dodged a bullet as well.

 

I hydro locked an engine w/gasoline once. It was freaky.

 

EXACT same thing happened to me in October of last year (2009). Except i did it all myself. Been running strong ever since. Had to do the same with the TPS as well. Houston weather...

 

Thnx but it felt more like I dodged a balistic missle!