stuck in a restoration.

[superj243]

I've been trying to restore my brothers 1981 280zx it seems that the mass air flow meter has went bad. (well im guessing thats the problem.) I've cleaned the gas tank, put a new fuel pump in it, new fuel filter, rubber gas lines, sparkplugs, cut out the catalatic converter, adjusted the timing, new coil, and a new air filter, but it still wont idle and run right. ive ran a full tank of gas with injecter cleaner out of it so im pretty sure its not the valves or injecters. somtimes it backfires and sometimes it just quits. doesnt have the power to climb the hill to get it out of my driveway witch is a shame because i just put new tires on it. Can someone confirm that this is the problem? And if it is is there anyway of replacing it with a more modern/cheaper alternative?

thanks in advance for all of your help.

[SteveJ]

What is the fuel pressure?

[psdenno]

Have you pulled the injectors to check their spray pattern?

Dennis

[Zed Head]

Define the current state of the idle. "Not right" doesn't give any clues about what's happening. Have you confirmed that there are no leaks in to the intake system? All air must pass through the AFM. Any leaks at all will affect the way the engine runs. Even leaving the dip stick out will have an effect.

[superj243]

What is the fuel pressure?

How do I check that?

[superj243]

The state and of idle is rough, when I can get it to idle at all. It backfires, quits, looses oil pressure and dies, other than the backfiring it sounds just lime an L28 should.

[superj243]

Have you pulled the injectors to check their spray pattern?

Dennis

I checked the 3 that I could get to without taking off the fuel rail. They seemed to be fine.

[SteveJ]

How do I check that?

Depressurize the fuel rail and install an inline fuel pressure gauge.

[EuroDat]

When you depressurize the fuel system, be carefull if you remove a hose to do it. The system can get up to 36psi. Not saying it will have that much pressure, but what pressure is in the system will spray all over the place and if you are unlucky, in your face and eyes.

I have heard of some people activate the cold start injector with a 9 volt battery to release the pressure. I like living dangeroisly and just loosened the hose clamp on the filter, covered the hose with a old towel and pulled it off the filter.

One other tip, release the fuel filler cap to make sure the tank has no pressure in it.

Chas