C-Dawg

hey everyone!

so, it's hot today and i took my 1983 naturally aspirated 280zx for a spin. T-tops off, windows down cruisin'! very nice!

then i decided to stop at a gas station to get a quick splash. when i finished, my car had a little trouble starting. when i turned the key, you can hear the engine turning and everything, but it just wouldn't fire up. i gave it a few seconds to rest, then tried again. same thing. on the third try, i gave it a little gas and it finally fired up. and ran perfectly.

it's not the first time this has happened, but it's the first time it took more than two tries to start it.

why? it has no trouble starting cold.

thanks!

BlueKitsune

The problem is vapor lock. Its caused by the fuel rail heating up from the heat of the engine. The simple fix is to floor it every time you start the Z when its hot. Um Im sure the a mechanical fix for it but I've never bothered with it

Yzzerdd

Well the 280ZX manual I got online says that when you start the car within 30(?) minutes of shutting it off, to put the pedal to the floor while starting and let off once started. Mine never gave me that trouble.

--Ryan

C-Dawg

hmm...

i've noticed that most of the solutions for zx problems is to floor it. thanks, i'll give try it next time : )

280zx2by2

one solution might be to reinstall (or fix) your injector cooling fan... thats what its for, to prevent vapor lock

BlueKitsune

I dont have mine. It NEVER turned on and it was a waste of space. nor did I feel like spending the money to fix it lol

Niku-Sama

the fan does nothing to be honest, its the fact that huge fuel maze on top of the engine has so much fuel in it and no place to go.

i've herd having a simple in one and out the other fuel rail fixes it.

280zx2by2

i never had vapor lock the first year i had my car (and when the fan worked) after it quit working (for reasons i don't care to look into) i would get vapor lock every time i restarted my car even after it sat for about 4-5 hours

imo it works and if it wasn't so damn ugly id probably try to put it back in and get it working again...

Niku-Sama

i'd get it whhen the fan was on and working, so go figure.

having that much fuel up above a hot engine is just asking for it either way

C-Dawg

so the real answer is to get a new fuel rail?

i don't really care for all the clutter around the engine. my car is stock and i don't mind putting new technology into it.

maybe i should wait until i undergo a major engine modification before i change the fuel system...

thanks guys : )

Niku-Sama

well thats my awnser since mine didnt do any thing to cool when it worked

Z350BOY

What about putting thermal tape around the fuel lines??

Niku-Sama

kind of like that fire proof stuff that they wrap arround lines and wires that go near the exhaust?

might work, could always try it

PurePontiacKid

or a heatshield... could end up looking cool if it covers up all the vacuum lines and stuff on the intake manifold...

Oh, and I just had a thought: I noticed after cleaning all the connectors on my thermostat housing that it no longer stalls like 10 seconds after it starts when it's cold, on top of no longer starting hard when it's hot/warm... just something to try, maybe even get new sensors...

Niku-Sama

got new sensors on mine and it still does it, oh wells

a heat sheild i could see as a potental disaster, well how you explained it.

covering those lines isnt what is needed you need things under them to keep the heat away from them, but a sheild might be overkill and hard where as the fabric should be alot easier to use

skib

Ill break it down into 4 simple options for you

1. do nothing and just deal with vapor lock.
2. reinstall a working cooling fan, because its obviously there for a reason.
3. instal an after market fuel rail
4. (properly) wrap your fuel rail in some thin heat wrap (The 240z/260z's had the rails wrapped to avoid vapor lock too)

My recommendation is to install/fix the factory cooling fan.

I drive an N/A 280zx and a 240z with an L28et, the ZX has the factory cooling fan and the turbo car has a custom made fuel rail and a lot of **** heat wrapped in the bay. Never have any vapor lock on either.

PurePontiacKid

did you clean out any/all the oxidation on the connector on the harness after you put the new sensors in?

Niku-Sama

new connectors even... cause i broke em off