Misfires, rough idle, and does the oil on the dipstick smell like gas?

Audi 3.0T Fuel Injector Replacement. Full Set
at your home.

2009–2017 Audi 3.0T TFSI B8-platform 3.0T TFSI Audi models 🟠 Big job, diagnosis confirmed before anything is booked

By 70–100,000 km the 3.0T's six Bosch injectors leak down and their seals weep fuel into the oil. We replace the complete set with new seals at your home, in one visit.

Get a Flat Quote Call/Text 647-450-0406

What's actually failing.

The Bosch direct injectors in the supercharged B8-era 3.0T live a hard life, seated in the combustion chamber, cycling at high pressure, exposed to full combustion heat. By 70–100,000 km they leak down: the internal sealing surfaces wear until injectors dribble after they should have closed, and their spray patterns degrade from a precise cone to an uneven spit. Cylinders stop receiving matched fuel charges, and the engine tells you with P0300-series misfire codes and a rough idle.

The second failure is sneakier: the injector seals weep fuel past them into the crankcase, diluting the engine oil. Fuel-thinned oil loses film strength, and that's the oil protecting your bearings, cam lobes and turbocharger journals. You can catch it on the dipstick: a level mysteriously rising, or oil that smells distinctly of gasoline. Oil dilution is a quiet engine-killer because nothing about it feels wrong from the driver's seat.

On a six-injector engine at this age, replacing the failing one or two is false economy: the others share the same hours and the same wear, and access on this supercharged V6 is the bulk of the labour. The proper repair is the complete set, six new injectors, all new seals, bringing every cylinder back to a matched baseline and stopping the dilution at its source.

The symptoms.

If your Audi is doing any of these, this is the likely cause:

  • Misfire codes (P0300–P0306), sometimes wandering between cylinders
  • Rough idle, worst when cold
  • Oil level rising between changes, or oil smelling of fuel
  • Fuel smell at the dipstick or filler cap
  • Worsening fuel economy
  • Hesitation or stumble under load
  • Black, sooty deposits on spark plugs

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What this job typically costs.

$2,500–$3,500
what dealers typically quote for this repair
Our approach is different: one flat quote for the complete job, given before any work starts, parts, labour, everything. No hourly meter, no surprise add-ons. And if a smaller fix solves it, that's what we'll tell you.

See how that range compares across Mississauga, Oakville, Milton, Brampton and Etobicoke in the GTA Repair Price Index, honest shop & dealer ranges for the jobs people actually get done.

Confirm it first

Let's confirm the diagnosis before anyone spends this.

Fuel Injector Set Replacement (All Six) is a big job and shops quote $2,500–$3,500 for it. The single most valuable thing you can do before committing that is have the diagnosis confirmed independently, $100–$250 flat, at your location, no hoist needed, because a diagnosis isn't the repair. Plenty of cars arrive at that quote and turn out to need the smaller version of the problem.

And the honest scoping condition, up front: once I've seen it, I tell you straight whether it's something I can do at your place. If it needs a hoist, a press or a machine shop, I say so and point you to someone who has one. I don't take a job and figure it out in your driveway. That's the whole deal, and it's why the diagnosis comes first.

Get it looked at, and get a quote

What the car is doing plus what you've been quoted. Fares reads his texts between jobs.

Straight answer including "this one belongs in a shop". Or call/text 647-450-0406.

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The complete fix includes.

  • Six new injectors, the complete set
  • All new injector seals and one-time-use hardware
  • Engine oil and filter change to clear fuel-diluted oil
  • New spark plugs if fouled
  • Fuel system leak check and rail pressure verification
  • Fault-code clear and road test
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How this works at your home.

A full-day job at your home. Reaching the injectors on this supercharged V6 takes real disassembly, that's where the hours go, then each injector seats with new seals and exact torque, followed by a leak check before the engine runs. We finish with an oil change, because driving off with fuel-diluted oil would undo half the point of the repair. No hoist needed; it's methodical top-of-engine work.

Why not to wait.

Two damage paths run in parallel. Misfires dump unburned fuel into the catalytic converters, which overheats and ruins them, cats for this car are an expensive add-on to what should be an injector job. Meanwhile fuel dilution is thinning the oil protecting every bearing in the engine, and bearing wear is cumulative and irreversible. Neither path announces itself loudly; both are well underway by the time the misfires are constant.

Frequently asked questions.

Can injectors be replaced at my home?

Yes, it's a day of careful top-of-engine work at your driveway: disassembly for access, six injectors seated with new seals at correct torque, a leak check, and a fresh oil change before the road test. Everything needed comes with us.

Why does a set of injectors cost what dealers charge?

Six precision direct-injection units are genuinely expensive parts, and the access labour on the supercharged V6 adds most of a day at dealer rates, hence $2,500–3,500. We quote one flat price for the complete set, seals, oil change and testing before any work starts.

Can you replace just the bad injector instead of all six?

Mechanically yes, economically no. The access labour is identical for one injector or six, and the remaining five have the same mileage and the same wear curve, replace one now and you're paying the teardown again within the year. One matched set, one labour bill, done.

What's the deal with fuel getting into my oil?

Worn injector seals let fuel weep past into the crankcase, where it thins the oil. Thinned oil can't maintain the protective film your bearings and turbo journals depend on, it's engine wear happening silently. New seals stop the leak, and the included oil change clears out what's already diluted.

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Send it over for a free second opinion. I'll tell you straight what the job actually involves, and if their quote is fair, I'll tell you that too.

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Is your Audi doing this right now?

Describe it to the AI mechanic, or send it to Fares below. We come to you in Mississauga, Oakville, Milton, Brampton and Etobicoke.

Get a Flat Quote Call/Text 647-450-0406

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