Owners logging CNG cars in this hub report typical mileage of 25–32 km/kg for compact hatchbacks (Maruti WagonR CNG, Alto CNG, Tiago CNG) against 18–22 km/l on petrol in the same cars — a running-cost cut of roughly 40–50% per kilometre at current city CNG prices. The most common complaint isn't mileage, it's queueing time at CNG stations during evening peak hours in cities like Delhi and Ahmedabad.
At a glance
| Metric | Typical community-logged figure |
|---|---|
| CNG mileage (compact hatch) | 25–32 km/kg |
| Petrol mileage (same car) | 18–22 km/l |
| Running cost saving vs petrol | ~40–50% per km |
| Boot space lost to cylinder | Roughly one-third of boot volume |
| #1 owner complaint | Refuelling queue times at peak hours |
What this diary hub tracks
This page indexes ongoing mileage and cost diaries submitted by True Motion Auto's Indian community members running factory-fit and retrofit CNG vehicles. Each diary tracks the same basics — fuel-up frequency, distance covered, cost per fill, and any maintenance issue — so readers comparing CNG against petrol or diesel can see real numbers across different cities and driving patterns, not a single owner's best-case month.
What the logs show so far
- Factory-fit CNG (Maruti Suzuki, Tata, Hyundai) consistently logs better and more consistent mileage than aftermarket retrofit kits, which vary more by installer quality.
- City stop-start driving drops CNG mileage noticeably compared to steady highway cruising — the same pattern as petrol, but owners note the percentage drop feels larger on CNG.
- Cold starts are usually done on petrol reserve tanks before the system switches to CNG, which owners in northern winters flag as worth budgeting a small petrol float for.
- Boot space loss from the cylinder is the most consistent lifestyle complaint, especially in hatchbacks where it can take out close to a third of usable boot volume.
Refuelling reality check
Multiple diaries from Delhi-NCR, Gujarat and Maharashtra independently flag queue times of 15–40 minutes at CNG stations during evening peak hours, driven by station density not keeping pace with the number of CNG vehicles on the road. Owners recommend fuelling mid-morning or late at night where possible, and treating the reserve petrol tank as a genuine backup rather than an afterthought.
Maintenance notes from the community
- Get the CNG cylinder's mandatory periodic hydro-test done on schedule — it's a legal safety requirement, not optional.
- Have injectors and the CNG kit serviced by an authorised centre; owners report rough idling as the most common early symptom of a kit needing attention.
- Track fuel-switch behaviour after cold starts — a system that won't switch to CNG promptly is usually a sensor or ECU mapping issue, not something to ignore.
- Log actual km/kg every fill for at least three months before drawing conclusions — short-trip city driving skews single readings low.
Factory-fit kits carry a manufacturer warranty and generally outperform retrofits on reliability and mileage consistency. Check local CNG station density in your daily commute area before committing — sparse coverage erodes the cost savings through detours and queue time.
How to add your own log
Submit monthly mileage and cost entries through the community dashboard; diaries with at least three consecutive months of data are pinned above one-off posts, since consistency is what makes this hub useful for people deciding whether to switch.
Frequently asked questions
What mileage can I really expect from a CNG car in India?
Is factory-fit CNG better than a retrofit kit?
How much boot space does a CNG cylinder take up?
Why do CNG refuelling queues take so long?
Does a CNG cylinder need periodic testing?
Sources & further reading
- Petroleum and Natural Gas Regulatory Board (PNGRB) — CNG infrastructure
- Ministry of Road Transport and Highways — vehicle fuel and emission norms
Figures, prices and policy details were current at the last-updated date above. Automotive pricing, incentives and regulations change frequently — verify time-sensitive details with the linked primary sources. Read our editorial policy and fact-checking standards.
