Intake pop/flap sound

[Zed Head]

Another thought that popped in to my head - the pressure inside the tank might contribute to the gassy smell by pushing fumes or liquid through any small leaks in the filler neck, in to the cabin.  But the tank's outlet and return lines will see the same pressure.  So it won't affect fuel pressure, since fuel pressure is between the pump and the regulator.  Doubtful that you would have over 28-36 psi of tank pressure under the cap since that would blow the tank up like a balloon.

 

Just saying, don't get distracted by the odd things.  There's a spring-loaded relief valve in the vent line that holds a small amount of pressure before venting.  And a valve in the cap to let air in if pressure goes negative.  So, the gas heats up, pressure builds, the gas cools down, the cap lets it reload.

 

Also, on fuel pressure - a clogged filter could lower flow and pressure.  Another simple fix, but only need to look at it if the measured pressure is low.

[urbtsx]

Not a problem zedhead, no offense taken.

I'm just listing all the things we notice, mainly to "think out loud".

Checking fuel pressure shortly

Sent from my Commodore 64 using Tap and Talk

[urbtsx]

Update:

Haven't been around much, finally found a tech who seems to have solved the issue. The guy installed a potentiometer. It's a small adjustable resistor that enables us to change the lean/richness.

Car runs beautifully. If anyone has questions let me know. this maybe a good place to start for the potential issues that the Z'a seem to have. After going through a slew of other suspicions that were not causing the main stuttering pre fire issue.

Thank you to everyone for their time, advice and comments. I'm hoping this has solved the issues.

[rcb280z]

Still would like to know what the problem was/is. There are several posts here regarding the "pot" install. People seem to like it. I have always fixed what was wrong not needing the "pot" fix.

Did the tech give you any idea what could be wrong? Why he decided on the pot.

[siteunseen]

Fastwoman's theory was the ecu would drift out of spec over the years causing the resistance to raise or lower. So it was get a new ecu or spend $5 at Radio Shack. I chose the $5 fix.

What like about mine is you get to tweak it on the fly. When I'm on the interstate I can lean it a little and get better MPGs and also lower the temp gauge. I've got mine in the passenger's floor board. Too lazy to hide it under the dash for now.

[rcb280z]

So tuning on the fly, I like that.