Oh, you mean jump start it. Then forget all the turbo stuff, we thought you were trying to put a turbo on it.

In that case, it probably backfired into the intake- maybe an injector was leaking fuel into the intake while it was sitting there, and it happened to backfire upon starting for some reason. Or maybe the FPR is damaged and leaking fuel into the VAC lines.

That would cause the intake to blow- I suppose its possible that the pressure got through the PCV system to blow the oil cap off.

There really isn't much you can do except start tearing it down to get rid of the damaged stuff- check all the gaskets up top too, that kinda pressure can damage gaskets easily.

The fuel pump is in the tank- that won't cause it. But its hard to tell you exactly what is messed up without looking at it. It doesn't have anything to do with jumping the car though- something was mechanically wrong inside the engine- likely something was leaking fuel.

 

My 2000 Monte SS did this 2 weekends ago. I had left it parked in the driveway for 3 weeks and left the GPS plugged in stupidly and killed the battery. The temperature outside was in the mid 20's F. I hooked up the other car to the Monte for a jump start. Waited a couple minutes. Never did I spray anything in there to help start it or any additional cranking with failure to start. Battery is 2-3 years old.

Turned her over to ON and listened to the fuel pump prime up, gauges all came up to normal, power looked good via the boosting car. Then turned to start and the engine turned maybe twice and BOOM! Explosion and flames shooting out the engine compartment. Blew the intake manifold all to heck.

 

I hear this happening alot when getting jump start. Is getting jumped the reason for this or is it cause the motors in a spot thats hard to start and thats why most think needs a jump?

 

Apparently the 3800 has a tendency to leak fuel into the intake manifold. Under daily driving it isn't enough cause issues, but leave it sitting for some time and enough fuel leaks in there that the conditions are right for an explosion, just need a spark!