Thank u guys. what I found so far today was a hole in the boot between AFM and TB. Tomorrow I will get new ones and I also have a new AFM(rebuilt of course). so let's wait until Monday. Have a great weekend everybody.

Hello Z Fanatics........

I post a few weeks ago about my 1976 280Z. The problem........backfire in the air mass meter. Car idle beautiful, has fuel pressure, no vacuum leaks, timing is good, I try to run it around the block, no power, backfires. Sometimes feels like she want's to go but she cannot. Anybody any idea? I will be more than thankful for any kind of help. If anybody in LA area is willing to help me I am willing to pay:):):).

Maybe a bit late but ...

Will it rev up without a load?

If yes, then I'd want to completely rule out a fuel supply problem before messing with the fuel injection system.

If no, then I'd suspect the ignition process, broadly defined. Timing, air leaks, ignition module, sensor malfunctions, or the electro-brain itself.

Best of luck.

Chris

This website is like a clinic! The best site on the internet for owners of old Z cars who aren't trying to blow their engines up with mods! *giggles*

Thank u guys. what I found so far today was a hole in the boot between AFM and TB. Tomorrow I will get new ones and I also have a new AFM(rebuilt of course). so let's wait until Monday. Have a great weekend everybody.

Might be a good idea to address your fuel tank soon too. If the car was stored for as long as it was...I'd have a healthy dose of concern for the inside walls of your fuel tank, in addition to the other matters at hand you are addressing.

It revs very nice. backfire only with load.I just found yesterday a hole in the boot bet. AFM and TB. today I got new boots, but I have to wait until Monday to install them.

Edited January 23, 201114 yr by cmiulius

It revs very nice. backfire only with load.I just found yesterday a hole in the boot bet. AFM and TB. today I got new boots, but I have to wait until Monday to install them.

Mine has carbs, so I'm guessing a bit here. A hole in an air duct between the Air Flow Meter and Throttle Body? Too much air would lean it out, same as not enough gas. That might well be your problem. If nothing else, having a hole there would certainly complicate troubleshooting so it has to be fixed anyway.

Just a thought: If the new boots solves most of the problem, but not all, could a PO, unaware of the air leak -- which was also probably smaller at some time, have adjusted the FI to compensate? And with the leak fixed, end up too rich? I leave the answer up to the FI people.

Chris

use some duct tape to wrap the boot in the groves and patch the hole in the mean time if you want to see if thats your issue. If you do have a leak between AFM and TB, it will definitely cause it to not run right.

I got new boots. I'm waiting for Monday to come to be able to install them. very expensive parts, 92 dollars both(original.) . Better work after this. :):):)