Hot engine no start

[Hughie3]

I have a V40 D4 engine starts perfectly cold but when it reaches normal temperature if it stops either stop start or switching it off it doesn’t want to restart. Have to crank and crank for ages when if lucky it will start. Drives beautifully just the not start when hot problems . Has anyone come across this problem.

[GrahamBrown1]

You will need to have a look at some live data via a diagnostic tool to see what’s going on. Sounds like it’s fuel system related. A Volvo plug in may pin point the issue with a fault code but some fuel data where I would start.

Depending on which D4 you have 5 cylinder or the newer 4 cylinder, I’d be looking at rail pressure when hot on a 5 cylinder. It may be an injector is leaking back when hot and draining the system.

The injectors on 4 cylinder engines monitor there own pressure via there own individual sensor but proper diagnosis is required. Anything else is purely guess work.

[Hughie3]

Had it diagnosed by nonevfranchise Volvo garage and they found the followingP00047B - Fuel volume control valve circuit high, mechanical fault, low fluid level. P13307B- injector control pressure lower than desired, mechanical fault, low fluid level. They referred me to a diesel specialist who are mainly Bosch specialist but my system is evidently Denso. They had the injectors tested and they were found to be within spec. They couldn’t help after changing air mass meter and crank sensor. So far spent close on a 1000 to no avail. Looks like I’ll have to bite the bullet and go to the local Volvo dealer.