Hi!

I have a Camaro Z28 -95 (LT1). I've changed the cam shaft to a LT4 hot cam. Then I was driving for about 100-300 miles after that and then the car was losing a lot of power. Every time I drove after that, it was just getting weaker and weaker. Now it will start when it's cold and run for 3 minutes and then it stops.
I switched spark plugs and tried to start, but it is still running for approximatley 3 minutes.
I have a diagnostic program that shows me Code 33- (MAP sensor high), and then I started to think that maybe there is something wrong with the vacuum system. When Engine is turned of, the MAP is the same as outside (this is why I think the sensor is OK but the reference is messed up). But when I start, everything looks normal but the MAP is rising constantly until it is almost as high as outside and then the engine stops again.

What do you suggest I do next?

Thank you!
/Patrik

 

put a vacuum gauge on it and see what you actually have. lifters could be pumped up, valves loose, hose off,?? loose intake,