I have a Renault Laguna automatic, 2 litre, three or four years old.
It suffers from an intermittent fault which prevents it starting
properly - the engine will catch and run for a second or so and then
stop. After doing this a few times the engine will not start at all.
Generally if the car is left for a day or so the car will then start
with no problems. The car has been to the local Renault dealer a
couple of times with this problem; they have replaced the idle valve
and run the standard tests on the immobiliser but have not found any
fault. I have heard suggestions that the fault may be due to water
ingress through the aerial socket or through the sunroof. Does anyone
have any experience of tracing and fixing this particular fault?

Hi lgab,

This page suggests a catalytic convertor
problem, and a battery problem:
http://www.carsurvey.org/viewcomments_review_5118.html

Unless you have a rattle underneath the
car, I'd say no to the cat convertor.

But what about the electrical. Have they
narrowed it down to air? fuel? elec? Could
it be a weak battery? Maybe a shorted
cell in the battery? Is the engine
cranking strongly, and then just dies?
Have they ran the car on an analyzer
while its is working/not working? Any
computer codes thrown? 

-AI

Hello,
I have a 1969 Datsun pickup that does the same thing. It is tuned up
and ALL but still has trouble starting. I have resorted to starting
ether as I am unwilling to grind on the starter. It also has a hand
choke and needs to be set just so. good luck. Bill in Oregon, USA