A comprehensive pre purchase inspection (PPI) is an incredibly valuable service to car buyers that shouldn’t be over looked. In a competitive used vehicle market like New Zealand, there are always dicey vehicles around that could catch people out. In-depth inspections can often uncover secrets of a vehicle’s past and protect your future investment.

Narrow your shortlist

Unless your house has money trees growing outside, you’re not going to want to fork out $150 on a PPI for every single vehicle you look at, so before you commit to shelling out the cash, take some time to partake in a bit of DIY PPI to whittle down the contenders.

Start by looking under the bonnet

Are there signs of leakage, corrosion or damage? Warming up the engine will make coolant leaks more apparent. A freshly cleaned engine bay doesn’t really tell you much about the vehicle. Just because it’s clean or tidy, doesn’t mean it’s problem free, so start with obvious indicators like the engine oil and lube sticker. Thick, black oil is a sign that the engine may not have received adequate servicing or, if the oil level is very low, it may have an oil leak or an oil consumption problem.

Give the engine a good rev from idle, up to about 3000rpm or half its maximum rpm. A worn engine is likely to smoke under these conditions.

What can a professional PPI tell me that I might struggle to spot myself?

• Diagnostic checks like compression tests, blow by tests and head gasket checks

• Signs of recent panel work, corrosion or evidence of stripping a vehicle – these are tell-tale signs of prior damage, rust or a vehicle that has had more hits than The Beatles

• Leaks need to be checked invasively too - From the engine and drive train, through to the cooling system

• Batteries need to be tested to ensure that they have a decent life left in them, while faulty electronic systems, including diagnostic warning lights, can also spell disaster

• A road test should be carried out to uncover issues relating to the vehicle’s transmission, drive line and braking issues

What a PPI can’t do.

No matter how good the inspection, a technician can only look at the vehicle that sits in front of them on the day. They can’t foresee the future, but they can draw your attention to warning signs of potential repairs or WoF failures – as long as they’re showing signs of materialising.

The end decision on buying the car though rests with you.