Hi, just a quick question to you guys with Aftermarket fuel regs with gauges on. How quickly does your fuel pressure drop after switching your engine off?
I would say mine starts dropping nearly straight away and pressure is fully gone in 2mins, is this normal or is my reg knackered?
Also would this have any effect whilst the car is running as the injectors have been maxing out slightly early on a recent dyno run.
Car has a new Rcm fuel pump and cleaned flow matched/tested injectors so should be able to rule them out.
Is their a check valve in the reg etc.?
Many thanks Tim.

 

Why would you want fuel pressure when engine is off???????? Strange!!!!!!!

 

My living room goes dark at night when I switch the light off I'm sure there should still be a little brightness left.think about it....SJ.

 

On a serious note what size injectors are you running and what's your bhp?FPR are usually set at around 3 bar fuel pressure when stationary and engine running,how do you know the injectors are maxing out,has your car been mapped properly?SJ.

 

Yes the car has been mapped properly! I've just had a small issue with the injectors maxing out a tad before they should. Was checking all possible cause's. ie fuel pump/injectors/reg/ etc. Just wondering what peoples afr did with regards to holding pressure and if the check valve could have any effect on things. Sorry for asking sensible questions, im forgetting this is scoobynet!!

 

I gave you a sensible answer mate regarding your fuel pressure with the engine switched off.as you seem to already know that you wont get a sensible answer on scoobynet why come on here and start a thread to get a answer to your question?.the only reason I asked if the car had been mapped properly was that the mapper would know what duty your injectors are running at to achieve your desired bhp,what make is your FPR?i also have the RCM fuel pump which is a good bit of kit so I doubt that's your problem.get a mapper to plug into your ecu and get some figures any good mapper should know how to diagnose your problem and point you in the right direction.SJ.

 

Check when turning the engine on, ignition, not turning over. Does it go empty in less than 2 mins as well?

I have the same and had 2 quality sx regs fitted for testing, part of the issue was my bosch pump had no return valve on it so soon as the pump stops pumping the fuel works its way back through the pump itself into the tank. I've since put inline pump in with very low fuel flow restriction and it's better but mines not better than 2 mins to empty, prob 1.5 mins but used to be 30 seconds.

To check the injectors, quick and basic way is to block the return pipe, prime pump once and if you have non-return, that will confirm injectors not leaking and fuel system pipes okay and just points finger at FPR.