System: Powertrain (P-Code)
SAE Standard (Generic)
Family: Alt Fuel Pump Performance
Code P2A90: Alternative Fuel Pump C Performance
Diagnostic & Technical Explanation
Code P2A90 (Alternative Fuel Pump C Performance) sets when pump A, B, or C is not delivering the fuel volume or pressure the ECM expects for its commanded duty cycle, despite the pump's individual circuits testing fine. A worn pump plunger or check valve, air trapped in the supply line from the tank, or a partially clogged inlet filter are the most common physical causes.
First-listed procedure
Rank #1
Check alternative fuel supply line for air or restriction
Easy DIY
This is the first procedure in the authored
consideration order, not a measured cause likelihood. Execute it only when its prerequisites
and diagnostic findings support it. Its cost and labor estimates (where known), the step-by-step procedure and the
remaining 2 procedure(s) are in the licensed dataset. Ordering context.
Full family: Alt Fuel Pump Performance
What this page does not show
This page publishes the fault mechanism and the code index. The licensed dataset adds, for
every one of the 15,886 codes, the full authored repair set (56,729 procedures in total)
with the fields deliberately withheld here:
- Procedures 2..n after the first-listed procedure
- Aftermarket parts cost ranges in USD (
est_parts_cost_min/max_usd)
- Professional labor-hour estimates (
est_labor_hours)
- Step-by-step diagnostic and repair instructions
- Replacement-part mappings and catalog lookups
- 6,637 manufacturer-specific OEM codes across 32 makes ($149 tier)