Hello

[Kev2575]

Hi I have a Mercedes’ 1999 clk320 need help with problem I can start the car it’s starts ok then drive to shop get back in it and it won’t start can be there for ages but leave it hours later it will or I start the car leave it running after about 10 minutes it cuts out and same problem it won’t start any ideas thanks

 

[SmartAmg]

Welcome, Kev.

 

[pgh13]

Hi Kev and welcome.
I'd be suspecting fuel. If you crack the filler cap, releasing any vacuum, does that help?
I've also seen reports of old seals in the fuel lines allowing air to be drawn in.

 

[Taffy7hfa]

Crank position sensors sometimes fail in this way. When it wont fire, see if the rpm counter moves when cranking.

 

[Kev2575]

Hi Kev and welcome.
I'd be suspecting fuel. If you crack the filler cap, releasing any vacuum, does that help?
I've also seen reports of old seals in the fuel lines allowing air to be drawn in.

Hi thanks I haven’t yet I will have go

 

[Kev2575]

Crank position sensors sometimes fail in this way. When it wont fire, see if the rpm counter moves when cranking.

Ok thanks I’ll have look

 

[Kev2575]

Hi Kev and welcome.
I'd be suspecting fuel. If you crack the filler cap, releasing any vacuum, does that help?
I've also seen reports of old seals in the fuel lines allowing air to be drawn in.

Hi just tried when it cut out and wouldn’t start took fuel cap off no vacuume there just came of normal

 

[Kev2575]

Ok thanks I’ll have look

Hi just tied it when it cut out no movement on rev counter when turning over

 

[AMGeed]

Crank position sensors sometimes fail in this way. When it wont fire, see if the rpm counter moves when cranking.

+1 for the CPS.

 

[brandwooddixon]

Crank position sensors sometimes fail in this way. When it wont fire, see if the rpm counter moves when cranking.

Agreed. A typical failure mode sees them working until they get warm/hot. This shows itself as either the car running until it gets up to temperature or if you've only driven a short distance heat soak whilst the engine is stopped warming the sensor up enough to fail.
It typically doesn't trigger a fault code either, but thankfully sensor and replacement isn't too costly.
I've had it happen on two different cars over the years.

 

[Kev2575]

Agreed. A typical failure mode sees them working until they get warm/hot. This shows itself as either the car running until it gets up to temperature or if you've only driven a short distance heat soak whilst the engine is stopped warming the sensor up enough to fail.
It typically doesn't trigger a fault code either, but thankfully sensor and replacement isn't too costly.
I've had it happen on two different cars over the years.

Hi thanks so the crank sensor recon try replacing