A check-engine light just tells you something is wrong. It doesn’t tell you what — and a $20 code reader from the parts store doesn’t tell you either. We come to your driveway with a professional scan tool, read both the live data and the freeze-frame data from the moment the light came on, and trace the code to the actual failed component. The difference matters: a P0420 code can be a catalytic converter, but it can also be an upstream oxygen sensor, an exhaust leak, or a coolant-burning head gasket. Knowing which one saves you from buying a $1,200 cat you don’t need.

What diagnostics covers

• Full OBD-II scan — engine, transmission, ABS, body, and SRS modules
• Live data stream review (fuel trims, O2 voltages, MAF readings)
• Freeze-frame data analysis
• Misfire detection per cylinder
• Smoke test for vacuum and evap leaks (where applicable)
• Written diagnostic report with the actual probable cause + recommended fix

We use a professional bidirectional scan tool — the same kind shop techs use, not the basic code reader. That lets us actuate components (turn the fuel pump on manually, cycle the EVAP solenoid) to confirm the diagnosis instead of guessing. The written report comes to your phone before we leave.

Our process — what to expect

1. Tell us the symptoms + when the light came on + any patterns (cold start? after refueling? highway only?).
2. Same-day or next-day arrival window.
3. Initial scan + code retrieval + live data review (15-25 minutes).
4. If needed, follow-up tests: smoke test, compression check, individual sensor verification.
5. Written report + plain-English explanation + repair quote if you want to book the fix.

Typical pricing for diagnostics in Fort Wayne

Diagnostic visits in Fort Wayne run $89-$120 for the basic OBD-II scan + live data review + written report. More complex diagnostics — smoke test for EVAP leaks, compression test, cylinder leak-down — add $40-$80 each. If the diagnostic leads to a repair we do that same visit, the diagnostic fee rolls into the repair total. If we have to come back to finish the diagnosis (waiting on a part or for a symptom to recur), there’s no second-visit fee.

When we send you to a shop

Certain manufacturer-specific diagnostics — German cars with Volkswagen/Audi VCDS or BMW ISTA, some Hondas with HDS — go faster with the manufacturer scan tool than with our generic professional tool. We’ll do the basic diagnosis first and tell you whether you’d benefit from a brand-specific shop. Same with networking issues across multiple modules on newer vehicles where you need the wiring schematic.

Service area

Diagnostic visits across Fort Wayne and into the surrounding Allen County towns — New Haven, Huntertown, Leo-Cedarville, Monroeville, Woodburn.

Frequently asked questions about diagnostics in Fort Wayne

Why is your diagnostic different from a parts-store free scan?

Parts stores read the stored codes and hand you a printout. They can’t read live data, can’t actuate components, can’t review freeze-frame data, and they don’t know your vehicle’s specific failure patterns. A code is a symptom, not a diagnosis. We use the same scan tool a dealership tech uses and we read the data the parts-store reader can’t see.

What if the check-engine light is off when you arrive?

Codes that triggered the light stay stored in the computer for a number of drive cycles even if the light goes out. We can still pull pending and stored codes, look at the freeze-frame data, and review the long-term fuel trims for clues. If the light is fully out and no codes remain stored, we’ll discuss the symptoms with you and decide whether to come back when the light returns.

Will you tell me what the actual repair will cost?

Yes. Every diagnostic visit ends with a written quote for the repair — parts, labor, expected time. You can have us do the work that visit if it fits, schedule a follow-up if it’s a bigger job, or take the quote to compare with a shop. The diagnostic report is yours to keep regardless.

Do you do diesel diagnostics?

Yes — light-duty diesels (Cummins 6.7 in Ram trucks, Duramax in GM trucks, Power Stroke in Fords). We have the scan tools to read manufacturer-specific codes for these. Heavy-duty commercial diesels with class-8 powertrains we don’t handle — those need a shop with the right scan tools and lift access.

How long does a diagnostic visit take?

Most diagnostic visits are 30-60 minutes. A straightforward code that points clearly at a single failed sensor we can confirm in 20-25 minutes. A multi-symptom case where the codes don’t point at one thing — like a rough idle plus a misfire plus a fuel-trim issue — can run 45-75 minutes including the follow-up tests. We’ll tell you a range up front.

Can I just have you tell me what the code means over the phone?

We can tell you what the code generally means, but we can’t diagnose your specific situation by phone — that requires actually seeing the data. Code-to-actual-cause is not 1:1 in modern cars. The same code on two different vehicles can have very different root causes. The on-site visit is what gets you the right answer.

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