SL55 starting problem

[pk311ymb]

Hi all, my SL won't start after being left in the Sun. I suspect fuel vaporisation but I suppose it could be a fuel pump on its way out? It is accompanied by the Emissions warning lamp coming on intermittently. Any ideas?

 

[BachelorDays]

You've got to give a bit more info. Does it crank, etc. How long has it been parked in the Sun?

 

[pk311ymb]

Hi - yes it cranks very well. It's not a battery problem. It was in the Sun for less than an hour. After a few tries it starts and runs normally.

 

[alexanderfoti]

Had you driven the car shortly before, and parked it up?

 

[BachelorDays]

Hi - yes it cranks very well. It's not a battery problem. It was in the Sun for less than an hour. After a few tries it starts and runs normally.

Warm engine that cranks but refuses to start until given a rest for a bit is almost always a crankshaft position sensor.

If it happens first thing in the morning too, or after the car has been sitting there for 3-4 hours, then I'd think fuel supply.

 

[alexanderfoti]

Was going to mention cps, they also tend to show failures on very hot days when stuck in traffic.

 

[pk311ymb]

Yes. I should have said it cranks very briskly once you engage the starter (key or keyless) and after 5 secs or more it stops cranking having failed to start.

 

[pk311ymb]

Crankshaft position sensor sounds plausible - would that illuminate the Emissions light?

 

[BachelorDays]

Was going to mention cps, they also tend to show failures on very hot days when stuck in traffic.

Your earlier question had cps written all over it.

 

[alexanderfoti]

Your earlier question had cps written all over it.

 

[alexanderfoti]

Crankshaft position sensor sounds plausible - would that illuminate the Emissions light?

Doesnt always light the check engine light, but it will log a fault code. Its approximately 50 pound part, from Mercedes, 1-2 hours labour to change.

 

[BachelorDays]

Crankshaft position sensor sounds plausible - would that illuminate the Emissions light?

You mean the Engine Management Light. CPS often doesn't throw its code. However, on my car it would - and the EML would come on too.

You could get hold of a cheap scanner (£10+) and get the codes. If the EML comes on, you'll have a code in there.

 

[pk311ymb]

OK chaps - next question - can I fix it (quite handy) or is it a garage job?

 

[alexanderfoti]

Its not difficult to actually replace, but access can be hard. Its located at 2 o clock in the bell housing at the back of the engine, and they can get stuck in place. Its held in with a Torq bolt