Whats is the reasons that will delay car starting after some time of driving?

Well, if its a fuel pump, I would expect that it well delay at all scenarios.

 The real cause was the EVAP solenoid purge valve was stuck open. which allowed the fuel vapor (coming from the fuel tank) to  accumulate inside the intake manifold. and that's why it would take some time to dispose all this vapor before it can start correctly. New cheap valve solved the problem100%

so many rezones can be the cause of this problem

but before we answer we should ask a few questions to be able to diagnose this problem correctly

1: What type of vehicle we are dealing with and what model

2: what type of engine (petrol or diesel fuel )

3: surrounding wither conditions  

4:when did the last service take place and what was done and by whom and if this problem was noticed  at that time

5:  problem occurred recently or it has bin there for a long time and how often dose it happen

6: what type of fuel was used ( normal or high octane ) and in some countries we also need to know for witch station was the vehicle  refueled

7: was there any change in fuel type from  high to normal octane or in some countries from unleaded to leaded

all of these questions should be answered  before any one can diagnose this problem

Thank you

this problem can a result of failure of the following components, starter motor solenoid, ignition coil ,camshaft position sensor,crankshaft position sensor. These component have coils when these coils are edging tend to fail when subjected to high temperature. But when the temperatures goes down these components do function again.

Hi,

If you are using a petrol fueled engine, the proper reason would be the petrol inside your carburetor/fuel injector (intake manifold) will be vaporized after turning off your vehicle. This is due to the heat from the engine that gets transferred to the intake manifold and thus, vaporizing petrol fuel as they are highly volatile.

In this volatile state, suction from a naturally aspirated engine would not be enough for the vapors to get sucked into the engine. So the engine delays a bit as it gets a fresh mixture of air and fuel from the carburetor or the fuel injector.

When your vehicle is turned off for a more longer period of time, the vaporized fuels will get beck to it's semi-liquid, semi-gaseous state, and will get sucked inside your combustion chamber as the engine gets cranked.

This would be the best explanation on the delays. Thank You...

car sensor are not working good

Some factors. Battery system, fuels system or the starting systems. These two are the common causes. 

starter need to be checked....it won't work properly when hot

to have tine of sufficient rotation for diesel engine 500 rpm and for gasoline 250 rpm must reach.provided proper cooling,lubrication,electric or compression to have fuel,heat & air ful filled.

For Gasoline  Cars 

The number one reason you should consider is the (Fuel pump ) xxxxxxxx very important (will solve the problem) 

number two 2 - is the crank sensor 

For Diesel 

Hard to be the same Problem  if so

Diesel With  ECM (Hiwee Engines )  hook up your adapter (OBD) to it by experience once you see the problem you should already have the solution in your mind and easy to solve

There will be might battery weak or self dynamo problem should be check properly with auto electrician