280zx underbody exhaust/drive train problem?
 

Hello everyone. 1982 280zx n/a manual.

I've searched and can't seem to find the answer to this problem, mostly because I don't know where to even start. I have 2 issues, possibly related.

1) This is getting worse, but the car seems to struggle accelerating when I goose it in 3rd gear or above.
I will shift into gear, hit the throttle, the rpms will jump again like they would in an automatic, but I'm already in gear.
They then settle back down and I can accelerate again.

2) when driving, there is a pinging sound under the car that changes tones with speed and gear. It doesn't affect the motor or appear to affect driving, but it sounds awful. I'm thinking it is a loose exhaust.

Any help would be appreciated. Thanks!

Well what have you checked? When was the last time you did a tune up? A basic tune up will do wonders for a tired motor: plugs, wires, cap, rotor, check sensors & connectors, etc.

All this is detailed in the FSM: XenonZcar.com S130 Factory Service manuals

My apologies but I just found the rattle. It was coming from a rusted heatshield. I'm thinking the rpm jump might be a sign that my clutch is going out? Just replaced the cap and oil but I'll try plugs and wires first. I've never replaced the clutch so I may look into that as well. Thanks!

A clutch starts slipping once it's worn out... So you hit the gas, rpms jump, you no go. :)

Oh, it might not be that then because I'm picking up a loud, resistant hum from the rear end of the car. It reminds me of the time my u-joint went out. Sorry about throwing all of these problems out there