R35 GT-R Pre-Purchase Inspections & Health Checks
Most used R35s have been modified. Plenty get the parts pulled off before sale — with the tune left in. We check what you're buying before you buy it, or sort the one you already own.
Gearbox concerns? See GR6 transmission repairs.
The Problem
When the tune doesn't match the car
An owner modifies their R35. When it's time to sell, the parts come off and go on the next project — but the tune stays in the ECU, still mapped for hardware that's gone. The new owner gets a car that runs like this:
Hunting idle on cold start
Likely cause: The tune is calibrated for intake or exhaust hardware that's no longer on the car
Down on power
Likely cause: The map expects mods that were removed before sale, so the engine never hits its targets
Low boost
Likely cause: Boost control mapped for downpipes or an exhaust that's gone back to stock — or a leak
Flat spots and hesitation
Likely cause: Fuelling mapped for injectors or pumps that were swapped back to standard
Heavy fuel use
Likely cause: The engine running rich because the tune's airflow assumptions no longer hold
Check engine light or limp mode
Likely cause: Fault codes from sensors and hardware the tune expects but can't find
None of this shows up in a seller's ad. It shows up in the ECU, on the dyno, and on a cold start the next morning. That's where we look.
What We Do
Before you buy, or after
Same workshop either way: we work out what's actually on the car, what the tune expects, and close the gap.
Pre-purchase inspection
Before you hand over the money. We go through the car and tell you exactly what you'd be buying.
- ECU + TCU read — is it tuned, and for what?
- What's fitted vs what the tune expects
- Boost, fuel system, and leak checks
- GR6 transmission health check
- Road test
- Written report — and a quote for anything it needs
Checkover + retune
Already bought one that doesn't drive right? We find what's actually on the car, fix what needs fixing, and retune to match.
- Full mechanical checkover
- Diagnosis of any running issues
- Custom dyno tuning w/ EcuTek — ECU + TCU
- Boost, fuelling, and cold start verified
- Dyno sheet + road test before handback
From the Workshop
One that came in exactly like this
This GT-R arrived with the full set of symptoms: hunting idle on cold start, down on power, boost nowhere near target. The tune in the ECU didn't match the hardware on the car.
We went through it, then wrote a fresh custom dyno tune w/ EcuTek — ECU and TCU — matched to what's actually fitted.
- Power
- 330.9 kW
- Torque
- 558.5 Nm
Cold starts clean, boost on target, shifts sorted. It drives the way a GT-R should.
FAQ
Common questions
- Why would a used R35 run badly?
- The most common reason we see: the car was modified, then the seller took the parts off before sale — but left the tune in. The ECU is still mapped for downpipes, injectors, or an intake that isn't there anymore. The result is hunting idle, low boost, flat spots, and a car that's down on power.
- What does the pre-purchase inspection cover?
- We read the ECU and TCU to see if the car is tuned and what the tune expects, then check what's actually fitted. Add boost and fuel system checks, a GR6 transmission health check, and a road test. You get a written report and a quote for anything the car needs — before you buy it.
- Can you inspect a car before I buy it?
- Yes — that's the point. Arrange with the seller to get the car to us at 8-10 Molan St, Ringwood, and we'll go through it. If the seller won't allow an independent inspection, treat that as your answer.
- The mods were removed before I bought it. Do I need a retune?
- If the tune was written for those mods, yes. A map calibrated for hardware that's no longer fitted will idle badly, run rich, and miss its boost targets. A retune matched to what's actually on the car fixes it — ECU and TCU.
- How much does it cost?
- Depends how deep you want to go — a pre-purchase inspection costs a lot less than the surprises it catches. Call or send the form through and we'll quote it before anything starts.
- What if the inspection finds problems?
- You get it all in writing: what's wrong, what it costs to fix, and what we'd walk away from. Use it to negotiate the price or to keep looking. Either way you're deciding with the facts.
Google Reviews
What our customers say
4.7 from 167 Google reviews
"Az and the Revzone team demonstrated care and took the time to explain everything in detail, making sure I understood all my options and felt confident throughout the process of purchasing an exhaust for my car. Their knowledge, honest advice, and customer service made the whole experience easy and stress-free. Highly recommend Revzone to anyone looking for professional, reliable, and passionate support for their performance car needs. Thanks team"
Yass Thomas
2 months ago
"Revzone did a great job fitting my cold air intake and tuning my VB WRX. Car is much more responsive down low and is perfect for a daily driver. Jeff was extremely helpful and insightful through the whole process and I would recommend to anyone looking for a tune of their car!"
Michael Chen
3 months ago
"I was lucky enough to come across Revzone many years ago now, and I will continue to be their valued client. To get great customer service, quality and value for money is not very common in any industry, let alone the car industry. Thank you for your help over the years. Brian"
Brian Hills
2 months ago
Looking at an R35?
Get it inspected before the money moves — or bring in the one that doesn't drive right. We reply within 24 hours.