I am writing to warn others about our experience with Nathan Evans and Denver Mobile Auto Repair. Our story is the same as other reviewers, just a different amount and different excuses. After thousands of dollars lost and weeks of being left with an inoperable bus, we called another mechanic to figure out what was wrong.
Here is the factual timeline of our experience regarding Nathan:
* First Visit (7/21/2026): Nathan forced a Diesel Particulate Filter (DPF) regen cycle, cleared codes, and assured us the bus was fit for service. He claimed he needed to get the Engine Control Module (ECM) code to make "proper DPF regen adjustments."
* Second Visit (7/31/2026): The DPF light returned within a week. Nathan collected full payment upfront to order a replacement blower motor and dome light. He also charged a fee for an "ECM computer code adjustment" to change DEF fluid temperature settings.
* Third Visit (8/7/2026): The DPF light returned a third time. Nathan claimed a faulty dosing head was the root cause and collected a 50% deposit to order the part.
Following the third deposit, Nathan went completely radio silent for two weeks. He finally texted claiming he was injured but would return the following week. We wished him well and asked for a timeline. He then vanished for another three consecutive weeks, completely ignoring all outreach.
After a month of the bus remaining inoperable, we cut our losses and hired an independent, certified technician. Here is what the new mechanic discovered:
* Fraudulent Diagnostic Charges: The manufacturer (Thomas Built Buses) does not even require or utilize the manual ECM code override adjustments Nathan charged us for.
* Severe Misdiagnosis & Negligence: The actual root cause of the DPF failure was inaccurate airflow and filter temperature sensors. Because Nathan failed to diagnose these faulty sensors, his repeated forced regeneration cycles could not actually clean the filter and kept feeding the ECM inaccurate readings.
* The Resolution: The new mechanic simply replaced the faulty sensors, baked the filters clean, and ran a standard regeneration cycle. The bus immediately passed its emissions tests and we successfully registered it the very next day.
Nathan charged us for parts never received, specialized labor that wasn't required or performed, and completely abandoned the job. STAY FAR AWAY from Denver Mobile Auto Repair and Nathan Evans and any of his other companies. We have officially filed a formal complaint with the BBB and the Colorado Attorney General's Office to have him investigated for fraud and to try and recover funds. read more
