Fuel Pressure Regulator Circuit Low
The KUBOTA-P0091 (Kubota) diesel fault code means: Fuel Pressure Regulator Circuit Low. This is a serious severity code.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- intermediate
- Estimated cost
- $20-$80 connector, $180-$450 SCV
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Common Symptoms
- Low power
- Stalling at idle
Probable Causes (Ranked by Likelihood)
- Open wiring to SCV Very Likely
- Corroded SCV connector (row-crop spray exposure) Likely
Step-by-Step Diagnostic Procedure
Wiggle-test SCV connector.
Ohm test harness end-to-end.
Frequently Asked Questions
What is Kubota code P0091?
Kubota P0091 means: Fuel Pressure Regulator Circuit Low. Serious code -- address promptly to avoid inducement / further damage.
Can I keep using my Kubota with P0091?
Serious fault -- you can move the machine to a shop but don't run it under load. Use Kubota Diagmaster software (dealer tool) for full diagnostics.
How much does P0091 cost to fix on a Kubota?
Repair cost range: $20-$80 connector, $180-$450 SCV. Compact-tractor labor is typically $110-$150/hr in 2026.
P0091 on Other Platforms
The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown: