Cranks but won't start. No error code
 

Hi everyone,

I have a 2008 e350. It cranks but will not start. When we plug in a diagnostic tool, it doesn't show any error messages.

So far we have tried replacing the crankshaft position sensor and are now looking at the fuel pump relay as a possible suspect.

Putting a few drops of gas in the air intake will start the engine.

Also, if the car is cold, such as in the mornings, the engine will start without a problem.

I know very little about cars... but could that be a MAF sensor issue? Since colder air is more dense, it allows "more" in in the morning.

Also, you should consider changing the title to "Car cranks but only starts when it's cold." The more descriptive the better. Maybe someone else has had a similar issue.

I hear there is a TSB for the 2008's to change 4 relays under the hood. Bad batch of relays suspect.