# Water in Oil and New Car Warranty — What You're Entitled to in NZ

> If your car under warranty develops water in oil, you may have rights under the Consumer Guarantees Act and the manufacturer warranty. Here is what NZ consumers need to know.

- Canonical URL: https://www.eek.nz/news/water-in-oil-new-car-warranty-nz
- Published: 2026-02-03
- Author: EEK Mechanical
- Publisher: EEK Mechanical, a trade name of Forman Pacific, LLC

## Manufacturer Warranty and Oil Contamination

If your vehicle is within its manufacturer warranty period and develops water or coolant contamination in the oil, you likely have a claim under the warranty — provided the contamination is caused by a mechanical defect rather than driver error (such as driving through deep water). Head gasket failures, oil cooler failures, and intake manifold gasket failures within the warranty period are warranty items.

## Consumer Guarantees Act (CGA)

New Zealand's Consumer Guarantees Act provides protection beyond the manufacturer warranty period. If a vehicle develops a fault that a consumer would reasonably expect not to occur at that age and mileage — such as head gasket failure at 80,000 km on a vehicle sold as reliable for 200,000 km — the CGA gives you rights against the seller regardless of the expressed warranty period.

## What Documentation You Need

For a successful warranty or CGA claim arising from oil contamination: maintain all service records showing the vehicle was properly maintained; get EEK Mechanical's Oil Contamination Report documenting the contamination type and source; and if the dealer disputes your claim, refer to the Motor Vehicle Disputes Tribunal (MVDT). EEK Mechanical's certified report is accepted as evidence by the MVDT.

## Dealer Tactics to Watch For

Some dealers may claim contamination was caused by driver error or improper maintenance. Having an independent technical report from EEK Mechanical — obtained before the dealer inspects the vehicle — establishes the contamination state objectively. Call us first.

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Source: https://www.eek.nz/news/water-in-oil-new-car-warranty-nz