Hey guys, I'm new here. I just bought a 1977 280z that has sat for the most part of 6 years. I have done a full tune up as of this far, but I'm still having one issue, and need a little guidance in the right direction. When I get the car under a load, no matter whatr speed or gear, it starts to cut out and miss pretty hard. The only part of the under hood ignition system that I have not replaced thus far is the Dizzy, simply out of laziness, but my old man seems to think I have a problem with the fuel injection system rather than the ignition. I know the car has a pretty big exhaust leak on the manifold, and I am just waiting for a new header to arrive to fix that problem. Other than that does anyone have any suggestions as to where I can look? Thanks in advance.

 

Welcome to ZDriver!

I would start by pulling all the spark plugs & checking all the tips. Check the color & check to see if any look different than the rest.

What did you do for the "tune up" ?
Also, what's the timing set to?
Have you checked the coolant temp sensor (square double plug on the thermostat housing), and the AFM?

 

I put new plugs in. Gapped at what the Hayens manual stated, but I can't remember off the top of my head. New rotor button, oil and filter, air filter. I did not remove the dizzy, once again out of laziness. It's got a new coil and igniter. The MAF is a remanned unit that has only been on the car for 3 months. I got a reciept from the guy I bought the car from for that. I'm not sure about the timing because I don't have a timing light.