Turbocharger Underboost
The BOBCAT-P0299 (Bobcat) diesel fault code means: Turbocharger Underboost. This is a serious severity code.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- intermediate
- Estimated cost
- $50-$2,500
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Common Symptoms
- Severe power loss / slow cycle times
- Black smoke under load
- Turbo whistle changes pitch
Probable Causes (Ranked by Likelihood)
- Split intercooler boot (radiator frame flex) Very Likely
- Stuck/sooted VGT vanes on Kubota turbo Likely
- Plugged air filter / plugged DPF creating back-pressure Possible
- Failed boost pressure sensor Possible
Step-by-Step Diagnostic Procedure
Pressurize intake with smoke machine and locate leaks.
Scan VGT position command vs. actual; command sweep via Service Analyzer.
Check DPF back-pressure and differential; force regen if indicated.
Frequently Asked Questions
What is Bobcat code P0299?
Bobcat P0299: Turbocharger Underboost. This code is reported on Bobcat equipment running the described engine family.
Can I keep working with Bobcat code P0299?
Limited operation only -- finish the current task then shut down for repair.
How much does Bobcat P0299 cost to fix?
Typical repair cost: $50-$2,500. Off-road diesel shop labor runs $125-$175/hr in 2026. Dealer diagnostic software (Bobcat Service Analyzer) is usually required.
P0299 on Other Platforms
The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown: