AEB: longer cranking after fuel pump change
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We were thinking we were running out of fuel pump capacity (fuel pressure gauge showed drop at WOT and higher RPM).
Upgraded to AEM 320lph. Since then
- need longer cranking to start
- run dry at about 1/4 on the fuel gauge
Any tips what might be causing the 2 symptoms?
Once had 'longer cranking' case (different car), traced it back to (assumption) new pump not having a built in 'check valve' that closes the supply line and maintains pressure in the fuel system (despite the manufacturer saying the pump HAD a check valve).
Could it be the AEM pump also does not have a suitable check valve, and allows the fuel system to depressurize when key off (and taking longer to pressurize when cranking)?
"Dry at 1/4 tank": I assume the pump (comes with foam spacer) does not slide down low enough (there is a 'step' in the OEM basket)?
Upgraded to AEM 320lph. Since then
- need longer cranking to start
- run dry at about 1/4 on the fuel gauge
Any tips what might be causing the 2 symptoms?
Once had 'longer cranking' case (different car), traced it back to (assumption) new pump not having a built in 'check valve' that closes the supply line and maintains pressure in the fuel system (despite the manufacturer saying the pump HAD a check valve).
Could it be the AEM pump also does not have a suitable check valve, and allows the fuel system to depressurize when key off (and taking longer to pressurize when cranking)?
"Dry at 1/4 tank": I assume the pump (comes with foam spacer) does not slide down low enough (there is a 'step' in the OEM basket)?
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