CM11 Santa Fe Fuel Issue
 

Hi All, and thanks in advance.
I have a 2010 Santa Fe with D4HB engine (the later engine with longer glow plugs). I'm now at a desperate point! It all started with taking a bit longer to start every time, got to the point of driving and it would restrict the RPM and power WITHOUT the engine light coming on. If i pulled over, turned off & restart, it'd be fine for a while.
progressed to if engine was put under load (3rd gear trying to accelerate) it would lose power & stall (engine power, not electrical).
it's now got to the point of can start if I give it a sniff of brakeclean, but soon as brakeclean is gone it will stop.
fuel pressure (via obd11) is reading 470kpa before cranking, reaching 1200-1500kpa while cranking, and when starts with brakeclean will reach 4400 then just drop to 470kpa. Which of course it stalls.
Battery good.
I'm assuming pressure sensor is ok as it's reading on obd11.
Pressure reg on fuel rail is receiving voltage during cranking.
Pressure reg audibly operates when external voltage is applied.
Solenoid on high pressure pump is receiving voltage. Unknown if/what this Solenoid does.
remove fuel line from filter outlet, plenty of flow from low pressure pump.
remove return line from fuel rail, same delivery as from filter (i would have thought no return flow until pressure is built in rail.).
I'm super desperate for assistance as I'm 100kms from nearest dealer. I have plenty of mechanical knowledge so I can check anything recommend.
Thanks again, looking forward to hearing some ideas.

Update as I continue.
solenoid on high pressure pump and fuel pressure reg, both receiving 9.5v. Which drops to 8.5v upon cranking.
glow plugs only receiving 3.5v, currently removing airbox etc to clean any & every earth & power connection i can find.

Appears there is insufficient power (Voltage) to the circuits.

I would suggest checking battery cables and connections and if removed, cleaned and reinstalled and no change battery might be suspect.

Thanks Hanky,
I've removed ground connections that I can find & cleaned them, same with positive connections including replacement of positive battery terminal.
Connected a jump cable from negative post to engine ground & a set of jump cables to a running vehicle to eliminate possibilities of bad battery.
unfortunately status remains unchanged.
If it makes a difference, vehicle sat unused for 6yrs. I replaced battery & used without issues for 8mths. Then the problems started to arise.
cheers

When a vehicle sets for a lengthy period of time, many things can be affected.
We don't know the condition of the battery cables internally and if there is a problem there it can affect everything within the vehicle.

Is there somewhere i can connect jump cable as a second cable? Like running from battery to starter on old school to eliminate the chance of cable issue.
battery to under bonnet fuse box??
Or am I better to lift said fuse box to check all elec connections under there?
Xheers

There is no good place to use jumper cables that are easily accessible to prove the original cables are defective.

The better way is to do a voltage drop test to verify the cables are not providing high resistance.

Once you start poking around under fuse panels ,you present the opportunity for other problems.

Ok, thank you.
I'll start on some voltage drop testing.
what you're saying makes sense as I've run into similar on PWC engines.
As time progressed the issue got worse, therefore as time went on the electrical issue got worse. I'm in a new location now that has a bad keyhole wasp problem, wondering if there's a nest under fuse/relay panel.
time will tell, I'll keep you updated.
thanks again

Great you are willing to tackle this, not hard to do.

Just a reminder, the vehicle circuit has to be under load, attempting to operate the starter, when measuring the drop.

Please let us know what you find, thanks.

Just a quick thought.
even though obd is reading rp. Etc. What's the chance of crank sensor causing this issue?