Warm start issues with VP 8.1

[BMAG]

I have a 2008 252, it starts strong cold but just about every time has an issue starting warm. It revs like the battery is dead and needs a few cranks to turn over. The battery’s are both strong. I have asked around and people have said it could be the ignition coils or fuel pump. Does any one have any experience with this? Thank you.

[Titaniumboy]

Last summer I found a loose connection at the battery switch. Luckily it wasn’t causing any symptoms or issues. I would first check that all of your connections are clean and tight between your batteries and the starter.

[AsLan7]

.
Hey bmag. So glad you found us.

Sounds like it may be fuel starved at times when warm. Do you have an ECU scanner? Could be a sensor, fuel injector, dirty flame arrestor, etc. Sometimes a loose connection manifests itself in a warmer engine. Tough to diagnose over the internet. Definitely want to get it checked out though. An EFI or MPI engine should start right up every time regardless of temperature.

And welcome aboard mate.

.

[Kate]

"it starts strong cold but just about every time has an issue starting warm."

Sounds like vapor lock. (And, yes, it can happen to fuel-injected engines.) If so, there are various fixes.

Could also be worn out battery cables, as it was for me. Replaced them, problem fixed.

[bruceb58]

If it is cranking over slowly, first thing I would be checking is battery terminals at both the battery and engine sides and battery switch.

When the engine is running, what is the voltage at the battery? What is the age of the battery?

[NautiWeasel]

I'm on the bandwagon with the battery cables, specifically the ground. Ground issues seem to be exacerbated when the engines are warm from my experience. I ran into a similar issue with my older truck (I know, not a boat, or a 8.1, but a GM small block). Point is, check all the grounds are getting good connection with no corrosion between the terminals and cable ends/grounding bolts. It's a cheap fix if that's the culprit, and easy to check off the list.