ZCar Forum banner
Status
Not open for further replies.
1 - 3 of 3 Posts

·
Registered
Joined
·
107,695 Posts
Discussion Starter · #1 ·
I've had this problem for quite some time but have not figured out a remedy.
When the car is hot and it sits for a while (like after running into a store for afew minutes), it is hard to start. Then after it does start it misses. After I rev it up and drive off (missing like crazy) the problem will go away.

If this is just vapour lock, what can I do? I've heard that insulating the fuel rail by the injectors helps this.

Suggestions please?
 

·
Registered
Joined
·
108 Posts
> I've had this problem for quite some time
> but have not figured out a remedy.
> When the car is hot and it sits for a while
> (like after running into a store for afew
> minutes), it is hard to start. Then after it
> does start it misses. After I rev it up and
> drive off (missing like crazy) the problem
> will go away.

> If this is just vapour lock, what can I do?
> I've heard that insulating the fuel rail by
> the injectors helps this.

> Suggestions please?

Injectors?? I thought Electronic fuel injection cars have no vapor lock problems!

On my carbeurated 260z--I've experienced the same problems--but have pretty much overcome them.

Basically it is the radiant heat from the engine/exhaust manifold when it is shut off that heats/boils the remaining fuel in the carbeurators/fuel lines. (look at where the manifold is in relation to the SUs--right next to each other!)

So when you come out of the store and try to drive the thing---the carbs have trouble with the vaporized fuel until the cool fuel from your gas tank reaches the carbs. All kinds of stumbling and no power symptoms(scary if you are accelerating out into traffic!)

On the 260z--there is an electric fuel pump in addition to the mechanical pump(unlike the 240)--the one on my 260Z was removed! So after hunting down a used one--the problem pretty much disappeared.

I would think on a carbeurated Z--an electric fuel pump would be the ticket. Or perhaps an electric fan that is independent of your electrical system--that is, a temp controlled fan that will run and cool off your engine while its shut off and then turn off after the engine is cooled down.

I would think insulating all the fuel lines would be a good idea for a EFI Z.

How about fashioning a heat shield out of steel to protect the carbs?
Well--hope this helps...

John
 

·
Registered
Joined
·
1,323 Posts
check your O2 sensor. When the car has a hot restart your O2 sensor must heat up to operating temperature before it starts working properly. I seriously doubt you would have any problem with vapor lock. It is probably because you have a heated O2 sensor.
 
1 - 3 of 3 Posts
Status
Not open for further replies.
Top