Interesting discovery

[steady88]

So I have a 1979 280zx and have been having an issue with my engine (1 of 2 issues preventing me from getting her registered). I have posted in another section about my problem a few months ago, but I think I may have narrowed it down to the fuel system in particular. The engine is running pretty rough and has a lack of power. I have noticed an interesting pattern though after working on it. Every time I open up the fuel system to work on it and then close it back up (reconnect and tighten all hoses) it runs great for around 5 - 10 minutes! What's going on here? I have replaced the fuel pressure regulator and installed a pressure gauge between the filter and rail and all appears okay. What on earth is going on!!!

 

I would appreciate your help, I'm so confused! 

 

Thanks! steady88

[pauly_adams]

I said it before and ill say it again, your getting a pressurised tank, theres a metal line that goes to the carbon canister put compressed air through it, mine keeps getting blocked but since ive disconnected the carbon canister and just let it vent to air ive had no issues

[steady88]

I said it before and ill say it again, your getting a pressurised tank, theres a metal line that goes to the carbon canister put compressed air through it, mine keeps getting blocked but since ive disconnected the carbon canister and just let it vent to air ive had no issues

 

Got it solved!!! I had tried what you suggested a while ago, but it made no difference. I have since tried driving with the fuel cap off and it runs perfectly! I think the valve in the fuel cap is stuffed and not letting air into the tank.

[Zedric]

I said it before and ill say it again, your getting a pressurised tank, theres a metal line that goes to the carbon canister put compressed air through it, mine keeps getting blocked but since ive disconnected the carbon canister and just let it vent to air ive had no issues

Allot of people on this forum don't seem to care about anti pollution gear. some of the quotes I've heard are just stupid. Evaporative  emissions control is so simple and effective, why not use it. The only difference between my 76' 260Z 2 seater and a modern car is the modern car uses the ecu to tell the carbon canister to purge instead of a vacuum line. I love my 76' 260Z 2 seater for allot of reasons, metric dash, evap emissions control but, when it came to the air injection pump and manifold, it was seeya later. I new back then I could make it clean and efficient and when it came to getting it road worthy it passed the emissions test by a big margin. Now days with precise EFI fuel metering and cat's there is no reason to have a planet killer. Yes I know that even if I could develop a pure hydrogen fuel solution with zero emissions the heat alone would still be a factor, but at least I'm trying to be cleaner. Just a thought guys.