Hello, this is my first post to this forum, as my '83 280ZX NA has never given me any grief, til now. Here's the numbers at 2529 RPMs:

HC Reading = 2357, Limit = 220
CO Reading = 9.57, Limit = 1.20

Background of my car:
I'm the 2nd owner, and it has 123,000 miles, about 6000 miles per year. I just did the following about a week ago - Mobil 1 oil, Oil Filter, NGK Plugs, Fuel Filter, EGR Valve, Cleaned the K&N Air Filter, new Turbo Muffler. About 4 months ago, I had the dizzy rebuilt by Kim at Idaho Z. And over the last couple of years, I've replaced the Plug Wires, Dizzy Cap & Rotor.

My mileage has definitly dropped, now at about 16.5 MPG, seems like it was around 20 MPG when I bought the car about 5 years ago. The car's running pretty good.

TIA...Robert

 

Replace the fuel pressure regulator! Your fuel pressure is probably sky high.

That's what mine was like. If you idle your car for a while (30 secs) and then give it a quick rev, do you see black smoke shoot out?

My stupid car failed emissions for the second time now... it got worse barely. I'm going for a new oxygen sensor next. Oh, replace your oxygen sensor too along with the pressure regulator.

 

Thanks BleachZee. Can I get the Fuel Regulator & Oxygen Sensor at NAPA, or are these Stealer items?

Where can I see a pic of your '70 Fairlady Z?

 

Yes, Napa should have both. Or, if they don't you can order them online from Importedcarparts.com

Page 2 and 3 of my Zdriver gallery has some Fairlady Z pictures.

https://www.zdriver.com/gallery/show...500&ppuser=464

 

I'm looking at my FSM. When you say Oxygen Sensor, is that the same as the Air Regulator?

Where did you get that '70 Fairlady Z? I've seen a Fairlady ZX here in ABQ, but the guy had swapped drive trains.

 

The oxygen sensor is on the exhaust manifold. The air regulator is the Air Flow Meter on the intake pipe.

I got the Fairlady Z in Washington. Its one in a million chance to find one. Especially the early ones with original drivetrain.

 

In case anyone cares, here's what I did to get thru emissions
1) Replaced the fuel pressure regulator
2) Replaced the O2 sensor
3) Replaced all vacuum lines
4) Fixed a leaking injector
Thanks for your suggestions BleachZee...Robert

 

Did you notice any difference in performance after all that?

 

No, not really, just better gas mileage

 

Oh, BTW I see that in the posts above I too was failing emissions. A new oxygen sensor did the trick.