Question 1

What is Kaiju Mechanic?

Accepted Answer

Kaiju Mechanic is an AI-powered car mechanic app available on Android. It lets you ask any car question, track your vehicle's maintenance history, scan documents with OCR, and optionally connect an OBD-II adapter for live sensor monitoring and diagnostic code reading. Most features work with any vehicle, while OBD-II features require a compatible adapter and a 1996 or newer vehicle.

Question 2

What vehicles are compatible with Kaiju Mechanic?

Accepted Answer

Most features in Kaiju Mechanic — including AI chat, maintenance tracking, and document scanning — work with **any vehicle**. OBD-II features (live sensor data and diagnostic code reading) require a compatible OBD-II adapter and a **1996 or newer vehicle**, as OBD-II became a standard requirement for vehicles sold in the US starting that year.

See our [tested adapter recommendations](https://www.kaijumechanic.com/adapters) for full vehicle-support details.

Question 3

Do I need an OBD-II adapter to use Kaiju Mechanic?

Accepted Answer

No, an OBD-II adapter is optional. The majority of Kaiju Mechanic's features — including AI chat, maintenance tracking, document scanning, and the vehicle health dashboard — work without any adapter. An OBD-II adapter is only required if you want to use live sensor monitoring or read diagnostic trouble codes directly from your vehicle.

If you do want live data, see our [tested adapter picks](https://www.kaijumechanic.com/adapters).

Question 4

Which OBD-II adapter do I need?

Accepted Answer

Kaiju Mechanic works with standard **ELM327** OBD-II adapters over **Bluetooth Classic**, **Bluetooth Low Energy (BLE)**, and — on Android — **Wi-Fi**. Generic "OBDII" v1.5 clones are widely available online and at auto parts stores and work well, and so do brands like KONNWEI. You'll need a **1996-or-newer** vehicle for live data (2008+ gives the most detailed data).

**Wi-Fi adapters** (like the Vgate iCar Pro Wi-Fi) are supported on **Android** too — tap "Using a WiFi adapter?" on the connect screen, join the adapter's network, and the app finds it automatically. (After plugging in or power-cycling a Wi-Fi adapter, give it a minute or two — its network can take that long to appear.) One thing to skip: **ultra-cheap no-name clones** with old firmware that don't answer ELM327 commands.

If your adapter pairs but won't connect, see **"My adapter pairs but won't connect."**

Want specific, tested picks? See our [adapter guide](https://www.kaijumechanic.com/adapters) — ranked and tested.

Question 5

How do I scan documents with Kaiju Mechanic?

Accepted Answer

Document scanning is available to all registered users — it is credit-gated, not Premium-only. To scan a document, navigate to the document scanning section of the app and use your phone's camera to capture the document. The app uses OCR to read the text and AI to extract relevant data automatically. Supported documents include service receipts, invoices, insurance documents, and vehicle registration. Each scan costs **5 AI credits** from your monthly pool (free users get 15 credits/month; Premium gets 300).

Question 6

Can Kaiju Mechanic tell if my ECU has been tuned or reflashed?

Accepted Answer

Kaiju Mechanic can tell you whether your ECU's firmware has **changed since you first scanned it** — it cannot tell you whether a car is currently stock.

Here's how **Tune & Flash History** works. Every tune, dealer reflash, and TSB update leaves a fingerprint in your ECU's firmware (the ECU Firmware Signature). Kaiju Mechanic reads that fingerprint over your OBD-II adapter and stores it. There is no factory database to compare against — **your own first scan becomes the baseline**, and every later scan is compared to it.

That gives you three possible results:

- **Baseline Recorded** — your first scan. We've saved the signature, but there's nothing to compare against yet, so this scan cannot tell you whether the car is stock.
- **No Change Since Baseline** — the signature is unchanged since your first scan. This confirms nothing has been reflashed since then; it does not certify the ECU is factory-stock.
- **Non-Factory Tune Detected** — the signature has changed since your baseline scan. Consistent with an aftermarket tune, a dealer reflash, or a manufacturer TSB update.

This is useful for:

- **Tracking your own tune version history** across Stage 1, Stage 2, or dealer updates
- **Catching unauthorized flashes** between service visits — scan before and after you drop the car off

Because the baseline is the first scan on your own device, this **cannot verify a "completely stock" claim on a used car you don't already own** — a first scan of an unfamiliar vehicle establishes a baseline and nothing more.

Tune & Flash History is a Premium feature and requires an ELM327 OBD-II adapter (Bluetooth Classic, Bluetooth LE, or Wi-Fi) plus a 1996-or-newer vehicle. Open any vehicle in your garage and tap **Tune & Flash Check** — the result appears alongside your VIN and ECU Software ID.

Question 7

Can I save photos or documents without an account?

Accepted Answer

No. Uploading photos, scanned documents, and other media requires a free account. Creating an account is free and takes less than a minute — it also gives you 500 MB of cloud storage so your data is backed up automatically.

Anonymous (signed-out) users cannot upload or save media.

Question 8

How do AI credits work?

Accepted Answer

AI credits are a unified currency used across all AI features — chat, DTC analysis, and document scanning. **Free users** receive **15 credits/month** and **Premium subscribers** receive **300 credits/month**. Credits reset at the start of each billing cycle and unused monthly credits do not roll over. Any registered user can also purchase additional credit packs (50, 150, or 500 credits) that **never expire** and are used only after your monthly pool runs out — free users pay the list price and Premium subscribers get a 20% member discount. If you upgrade to Premium, any unused free monthly credits are carried into your new balance.

Question 9

Can I buy more AI credits if I run out?

Accepted Answer

Yes — any registered (signed-in) user can buy credit packs at any time, not just Premium subscribers. Free users pay the list price; Premium subscribers get a 20% member discount:

| Pack | Credits | List price (free) | Member price (Premium) |
|---|---|---|---|
| Small | 50 | $2.49 | $1.99 |
| Medium | 150 | $4.99 *(Popular)* | $3.99 |
| Large | 500 | $14.99 *(Best Value)* | $11.99 |

Purchased credits **never expire** and carry over month to month. Anonymous (signed-out) users must create a free account first. Storage add-ons remain Premium-only.

Question 10

How much do AI features cost in credits?

Accepted Answer

Credit costs vary by feature and complexity:

- **AI Chat (basic):** 1 credit
- **AI Chat (advanced):** 3 credits
- **DTC Analysis:** 3 credits
- **Document Scan & AI Extraction:** 5 credits
- **Maintenance AI Insight:** 3 credits
- **Maintenance AI Recommendation:** 1 credit

Every registered user — free or Premium — spends from the same credit pool. Free users get **15 AI credits per month** usable on any AI feature; Premium users get 300/month.

Question 11

Do unused AI credits roll over to the next month?

Accepted Answer

Monthly plan credits do **not** roll over — they reset at the start of each billing cycle. However, **purchased credit packs carry over month to month** and **never expire**. The app always uses your monthly plan credits first, and only draws from purchased credits after your monthly pool is exhausted. And when you upgrade to Premium, any unused free monthly credits are carried into your new balance rather than lost.

Question 12

Is Kaiju Mechanic free to use?

Accepted Answer

Yes! Kaiju Mechanic has a free tier that includes 1 vehicle, 15 AI credits per month (usable on chat, DTC analysis, and document scanning), maintenance tracking, OBD-II live sensor data and code reading (with a compatible adapter), a basic vehicle health dashboard, and 500 MB of cloud storage. Premium ($8.99/month or $79.99/year) adds 300 AI credits/month, unlimited vehicles, 5 GB of cloud storage, and a 20% member discount on credit packs (credit packs themselves are available to all registered users at list price).

Question 13

Does the free plan include cloud backup?

Accepted Answer

Yes. Free users get **500 MB of cloud storage** with automatic backup and sync. If you switch devices or reinstall the app, sign back in with the same account to restore your data.

For more storage, **Premium** includes 5 GB of cloud storage, with optional add-ons available if you need even more.

Question 14

How do I upgrade my subscription?

Accepted Answer

To upgrade to Premium (you'll need a free account first — upgrading isn't available while signed out):

1. Tap the **gear icon** in the top-right corner of the screen to open **Settings**
2. On the credit balance card at the top of Settings, tap **Upgrade** — or tap any Premium feature prompt from anywhere in the app
3. Select your billing period — monthly ($8.99/month) or annual ($79.99/year — 26% off, 3 months free)
4. Confirm the purchase through the Google Play Store

Your Premium features are available immediately after purchase.

Question 15

What does Premium include?

Accepted Answer

Premium gives you everything Kaiju Mechanic has to offer:

- **Unlimited vehicles** in your garage
- **300 AI credits/month** for chat, diagnostics, and document scanning
- **5 GB of cloud storage** with automatic backup and sync
- AI-powered DTC analysis (plain-English trouble code explanations)
- Document scanning with OCR and AI data extraction
- Custom maintenance intervals
- Premium-only storage add-ons (+2 GB for $0.99/mo, +10 GB for $2.99/mo)
- A 20% member discount on credit packs (credit packs themselves are available to all registered users at list price)

Premium is $8.99/month or $79.99/year — 26% off, that's 3 months free.

Question 16

How much does Premium cost?

Accepted Answer

Premium is **$8.99/month** or **$79.99/year**. Paying annually is **26% off** the monthly price — that's **3 months free**.

Both plans include the same features: unlimited vehicles, 5 GB of cloud storage, 300 AI credits/month, AI diagnostics, document scanning, and more. You can upgrade from **Settings > Subscription** in the app.

Question 17

What's the difference between monthly and annual Premium?

Accepted Answer

Both plans include exactly the same features. The only difference is how you pay:

- **Monthly Premium:** $8.99/month — billed each month, cancel anytime
- **Annual Premium:** $79.99/year — billed once a year, 26% off (that's 3 months free) compared to monthly

You can choose your billing period when subscribing through **Settings > Subscription**. Annual billing is a good choice if you know you'll be using Premium regularly.

Question 18

Does annual billing save money compared to monthly?

Accepted Answer

Yes. Annual Premium is $79.99/year versus $8.99/month — that's **26% off**, or **3 months free**, when you pay annually.

You can choose your billing period when subscribing through **Settings > Subscription**.

Question 19

How much storage do I get, and what counts toward it?

Accepted Answer

Storage limits depend on your plan:
- **Free:** 500 MB (cloud)
- **Premium:** 5 GB (cloud), with optional add-ons available

Storage is used by vehicle photos, scanned documents, service record attachments, and modification documentation. The maximum file size per upload is **25 MB** on all plans.

Question 20

Are there storage add-ons available if I need more space?

Accepted Answer

Storage add-ons are available to **Premium** subscribers:

- **+2 GB:** $0.99/month
- **+10 GB:** $2.99/month

Storage add-ons are separate subscriptions from your Premium plan. You can add, change, or cancel them independently through Google Play.

Question 21

How are payments processed?

Accepted Answer

All payments are processed through the Google Play Store. Kaiju Mechanic does not collect or store your credit card information directly. All payment processing is handled securely by Google Play.

Question 22

How do I restore my purchases after reinstalling the app or switching devices?

Accepted Answer

To restore your subscription and purchased credits:

1. Sign in with the **same account** you used when you originally subscribed
2. Make sure you're signed in to Google Play with the same Google account that made the purchase
3. Go to **Settings** > **Subscription** and tap **Restore Purchases**

The app re-checks your purchase history with Google Play and restores your plan and any purchased credit packs.

If nothing is restored, the usual cause is a different Google account in the Play Store than the one used for the original purchase.

Question 23

What happens if my payment fails?

Accepted Answer

If a payment fails (for example, due to an expired card), the app shows an **orange banner** at the top of the screen explaining the issue. Credit-consuming AI features (chat, DTC analysis, document scanning) are blocked until it's resolved, and the banner links straight to your payment settings in Google Play.

Update or replace your payment method there and Google will retry the charge automatically. Once it succeeds, full access is restored — usually within a few minutes.

Your purchased credits are unaffected; they never expire.

Question 24

What happens to my data if I cancel or downgrade?

Accepted Answer

Your data is preserved when you cancel or downgrade — we don't delete anything just because you changed plans. Here's what changes:

- **Vehicles:** All your vehicles stay in your garage and remain fully functional — you can view, edit, and run diagnostics on all of them. New vehicle creation is paused while you're over the free plan's 1-vehicle limit. Upgrade anytime to add more.
- **Credits:** Unused monthly plan credits reset at the end of the billing period. Purchased credits **never expire** — they stay in your account and remain spendable on the Free plan, so you don't need to re-subscribe to use them.
- **Files:** All files are preserved. If your storage exceeds 500 MB (the free plan limit), new uploads are paused until you free up space or re-subscribe.
- **Service Records:** All maintenance history is fully preserved.

Note: Accounts that remain inactive for an extended period may be subject to our data retention policy. We'll always notify you by email before any action is taken.

Question 25

How do I get a refund?

Accepted Answer

Kaiju Mechanic subscriptions and credit packs are billed by **Google Play**, so refunds are handled there rather than by us directly.

To request a refund, go to [play.google.com/store/account/subscriptions](https://play.google.com/store/account/subscriptions), find Kaiju Mechanic, and use Google Play's refund process — or contact Google Play support.

Kaiju Mechanic cannot process refunds directly. If Google Play has already declined a request and you think there are circumstances we should know about, contact our support team and we'll help where we can.

Question 26

How do I cancel my subscription?

Accepted Answer

Subscriptions are managed through the Google Play Store:

- **Android:** Google Play Store > Profile > Payments & subscriptions > Subscriptions > Kaiju Mechanic > Cancel

You can also start from inside the app: tap the **gear icon** in the top-right corner to open **Settings**, then tap **Subscription** ("View renewal, change, or cancel plan") — it takes you straight to your Google Play subscription management. That row only appears while you have a Premium subscription. Your premium features remain active until the end of your current billing period, after which your account reverts to the Free tier. All your data is preserved.

Question 27

What happens to my add-ons if I cancel Premium?

Accepted Answer

Storage add-ons are **separate subscriptions** from your Premium plan, so cancelling Premium does not automatically cancel your add-ons. You'll need to cancel them separately through the Google Play Store if you no longer want them.

To cancel a storage add-on:
- **Android:** Google Play Store > Profile > Payments & subscriptions > Subscriptions

Credit packs are one-time purchases, not subscriptions — they're not affected by cancelling Premium. Any purchased credits remain in your account and are available when you re-subscribe.

Frequently asked questions

General

Product Features

AI Credits

Billing & Plans