280Z shakes when the rpms are between 1300&1800 please help
 

why would my 78 280Z shake when ever the rpms are between 1300 and 1800? also why would my rpms go up several hundred rpms when I pump the brakes? you can reply to tuffytime@msn.com thanx, Marc

Welcome to ZDriver!

Have you checked the basics?
-Have you checked the timing? What is it set to?
-Have you adjusted / calibrated the TPS?
-Have you checked the fuel pressure?
-Have you adjusted the AFM?
-Have you cleaned all sensor connections?
-Have you wiggled the ecu plug wires?
-Have you checked the spark plug tips to see if they are all the same? Wet? Dry? Color?

You might have a leak in the hose from your intake manifold to the brake booster or a leak in the booster itself. Check all the vacuum hoses and the large intake hoses to the throttle body.