Stoffl

built BP NA with MS3 basic and NBFL purple injectors, all new injector seals

I've noticed that when I cycle the ignition on/off repeatedly within a shorter timeframe the engine appears to get flooded or the plugs get wet ?
This is just an assumption but the symptoms were AFR gauge reading pretty rich before start attempt and that the engine wouldn't start even after 10seconds of the starter motor turning it over. In both instances I was troubleshooting a airbag controller issue and cycling ignition on/off to check if the airbag light would shut off again after 8 seconds.
First instance I just let it sit for a couple hours after wasting 2h troubleshooting and double checking stuff in the engine bay. Then it started without issues.
Then same thing yesterday, noticed it wouldn't start again so I let it crank with wide open throttle for ~10s and after a bit of struggling and and some throttle it started again.

Now my question: is this normal behaviour - does repeatedly priming the fuel pump cause the injectors to leak into the combustion chamber ? Or just spray way to much fuel into the manifold due to built up pressure ? Or are some of my injectors failing and leaking ?

redursidae

If you post your tune we'll be able to tell exactly. It's likely that you have Prime Pulse enabled so every time you turn on the ECU it does a priming spray. Do it enough and you could flood it some.

Stoffl

huh figured I'm missing something obvious.

Yeah this is how my priming pulse table is setup currently.




I'l try to remember to zero out that table next time, thanks m8!

redursidae

Yep, that would do it! You're welcome. Glad it was something simple.

Zaphod

I would leave that priming pulse as is- if you need to switch the car on an off multiple times just floor the throttle while doing so- this will keep the priming pulse from happening (Flood clear TPS setting in the Cranking/Startup settings.

Greets
Sven

Stoffl

Right, wasn't aware this would also affect the priming pulse. Also a good shout.