Well today me and my brother changed my head gasket,it was blown, and we changed the timing bekt and water pump, well we put everything back on and we turned it on, and it turn on fine but once we turned it on it would accelerate to 3000 RPM then fall suddenly to 1000 RPM then to 3000 RPM etc..We're not to sure what it is, but tomorrow we're gonna try and figure it out..Any Ideas what it could be??Please help

 

check for vacuum leaks and make sure all vacuum lines are hooked up

 

Also did you use the head checked to make sure it wasn't warped?

 

Sounds like a vacuum leak. Make sure you plugged the lines back where they were

 

Also could be an intake air leak from the TB or IM gasket.