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Reanimotion Reanimotion is offline
umop apisdn
Join Date: Jun 2014
Location: Brisbane, Australia
Posts: 507
stock efi pressure is usually 45 psi and most quality injectors seem happy to operate normally up to around 75 or more
there are several YouTube videos comparing counterfeit injectors against genuine and the Chinese knock-off will generally shut down as pressure rises over 60, according to the fellow on the video Bosch will usually run up to 120 (see )
Delphi/Siemens-Deka should be similar to Bosch

I only have the logs to go by so the pressure plateau we are seeing on the sensor log may be something other than a stuck needle.
But Cranking and therefore low battery voltage and therefore limited voltage for the injector to work with against the high fuel pressure points to it not opening under those conditions

as to the no Fuel delivery, I should say "little to no" as there may have been some, but there could also be none
The air plate needs to move a little away from the resting point to begin the fuel flow. With a massive CP and little vacuum when cranking, it's possible the plate and arm did not move enough to provide enough fuel to open the injectors

the ImmediateWarmCrankNoStart log
showed a 13.3AFR and control pressures peaking at 702kpa (103PSI) @ 90% duty on the first run
cranking at 240rpm which seemed to catch but die after peaking at 1000RPM
the second was similar but cranked longer at 310RPM no catch

If the AFR can be trusted - and as there was a loose connection then I'm guessing by the flat line and same AFR that it was probably peaked at max lean not 13.3 - then I'd say there was little to no fuel delivery

1981 928S 4.7 ROW with KE3-Jetronic and Franken8 (AEM Inifinty) "Be the man your dog thinks you are."
Yes! mechanical/hydraulic constant flow injection can be managed by a modern EMS
Old 02-12-2017, 09:39 PM
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