A plain-language read on what your Cummins, Duramax, or Powerstroke is telling you.
TorqueTrace turns your year, make, model, symptoms, and OBD-II or scan-tool details — including diesel codes like P20EE, P2463, P0401, and P0299 — into a credible first-pass report you can actually take to your mechanic. No upsell. No mystery.
- Founded by an ASE-trained technician. Built by a working mechanic, not a content marketer.
- Preliminary, not a diagnosis. Designed to sharpen the shop conversation, not replace it.
- Built for Cummins, Duramax & Powerstroke owners — plus gas and hybrid.
Active regen repeating + P20EE
Likely cause
Degraded SCR catalyst or a stuck DEF injector at this mileage band — both common on the 6.7L XCP. Possible NOx sensor drift on bank 1.
Confidence
MEDIUM. P20EE alone is multimode — the regen interval is the tiebreaker.
Next step
Have the shop pull live pre-/post-SCR NOx data before replacing the DEF injector. Skipping that step turns into a costly cat replacement.
Serious reads for serious trucks.
Three families we cover in depth — each with its own failure modes, scan codes, and shop conversation.
Cummins 2500 / 3500
5.9L ISB · 6.7L ISB (XCP)
Turbo / emissions / EGR / fuel rail
- Active regen every 100–150 mi
- P20EE DEF efficiency low
- Limp-mode after cold start
- Hard start under load
Duramax (Chevy / GMC)
LB7 · LLY · LBZ · LMM · LML · L5P
Injectors · FICM · DPF regen · oil cooler
- P2463 soot-load high
- Crank no-start cold
- White smoke on cold start
- Power loss under tow
Ford Powerstroke (Super Duty)
6.0L · 6.4L · 6.7L
EGR cooler · FICM · turbo · IPR / ICP
- P0401 EGR flow low
- Stiction / cold rough idle
- Turbo whistle under load
- Hard start after short trips
Five inputs in. One plain-language report out.
No invasive OBD-II pairing. No app download. You describe the truck or car and what it is doing — the same intake works for diesel scan codes (P20EE, P2463, P0401, …) and gas/hybrid OBD-II trouble codes.
Year
Model year. Trim level optional. We pull the relevant generation context.
Make & model
Manufacturer + model + trim. Powertrain info improves precision.
Engine / drivetrain
Engine size, transmission, drive layout. Optional but recommended.
Symptoms
In your own words. Sounds, smells, when it happens, how often, under what load. Diesel-friendly notes — regen cycles, EGR / DPF activity, cold-start behavior.
OBD-II / scan details
Paste trouble codes (P0420, U0100, …) or a photo of the scan-tool readout. Diesel scan codes (P20EE, P2463, P0401, P0299) work the same way.
A report you can actually take to the shop.
Synthesized, ranked, and explained — without the upsell verbiage you usually get when you search your own car's symptoms.
- Likely root causes ranked by probability against your symptoms.
- Plain-English explanation of what each suspect means — no jargon wall.
- Recommended next step: self-fix, scan more, or take it to a shop.
- A summary sheet you can forward, screenshot, or hand to your mechanic.
What the report actually looks like.
Excerpts redacted from a real-shape diagnostic. You will see this style of prose in your own report.
Symptom reported
Active regen every ~120 mi + P20EE DEF efficiency low after refill.
Most likely a degraded SCR catalyst or a stuck/leaking DEF injector — both common in this generation at this mileage band. Could also be a NOx sensor drift on bank 1.
Confidence: MEDIUM. P20EE on its own is multimode — the regen interval is the tiebreaker.
Next step: Have the shop pull live NOx sensor data (pre- and post-SCR) before replacing the DEF injector. Replacing the cat first is the costly miss here.
Symptom reported
Rough idle at startup, smell of unburned fuel on cold mornings.
Most likely carbon-fouled idle air control valve + contaminated intake tract.
Confidence: HIGH. Three of your symptoms line up with a single, cheap-to-test cause.
Next step: Have the IAC removed and cleaned ($60–120 typical). If roughness persists past startup, ask the shop to spot-check the purge valve.
Symptom reported
HV battery warning light, intermittent.
Hybrid battery module imbalance or a failing cell. Do NOT continue driving — the vehicle may unexpectedly lose propulsion.
Confidence: HIGH (symptom-level). Exact module diagnosis requires scan + dealer-spec test.
Next step: Stop driving. Have the vehicle towed to a Toyota-certified hybrid shop for a battery health inspection. Do not DIY charge.
One flat fee per report.
No subscription. Pay once, get one plain-language preliminary diagnostic report tied to the intake you submitted.
- One diagnostic report from your submitted intake.
- Plain-language write-up — no jargon wall.
- Summary sheet you can forward or screenshot for your mechanic.
- Free re-read if symptoms change within 30 days.
- Honest confidence flags — not every report is a near-certain answer.
One-time charge. No subscription. No automatic renewals. Stripe-hosted secure checkout.
Important: this report is preliminary guidance, NOT a diagnosis.
Read this before you submit an intake.
A TorqueTrace report is a synthesized first read based on what you submit. It is not a substitute for an in-person inspection by a qualified mechanic, dealer service tech, or specialist.
It does not replace scan-tool data collection, lift inspection, test drives, or warranty verification. Use it as a smarter starting point for a shop conversation — not as medical-grade advice about your car.
If your situation matches any of the items below, stop driving and contact a qualified mechanic before submitting an intake or relying on a report.
Stop driving and contact a qualified mechanic if any of these apply:
- Brake warning light, soft / spongy pedal, grinding, or any brake fluid leak.
- Steering pull, hard steering, visible fluid leak under the front end, or a clunk on turning.
- Smoke from the engine bay, exhaust, or under the car. Pull over safely and shut off.
- Fluid leaks you cannot identify — coolant, oil, transmission, brake fluid, fuel.
- High-voltage battery warning on a hybrid or EV. Do not continue driving — the vehicle may lose propulsion.
- Any smell of burning electrical insulation, fuel, or hot coolant.
The TorqueTrace team
Founded by an ASE-trained technician
The founder grew up turning wrenches in family shops and spent years turning customer-facing diagnostic explanations into a quieter, less mystified conversation. TorqueTrace is what they wished every owner had before the shop visit: a credible first-pass read that explains what is going on, what is not, and what to ask for next.
Want in early? We open a closed beta before the public launch.
Apply to join the closed betaThe intake shape is locked. The pipeline ships next.
Below is exactly what a real intake will ask for when it opens. Until then, drop your email — you will be the first to hear when reports ship.
Here is exactly what we will ask for.
- Submit year, make, model, trim, and engine/drivetrain.
- Describe symptoms in your own words — sounds, smells, when and how often.
- Paste OBD-II trouble codes (P0420, U0100, …) or upload a scan-tool readout.
- Optional: recent service history, mileage, driving environment.
Every intake goes through human-readable intake review before it ships, so what we ask for is what we will actually synthesize against.
Drop your email — we will open intake once the diagnostic pipeline ships.
We will only email you about TorqueTrace launch + closed beta. No drip marketing.