Credov's researched list of the 4 faults the Lexus GS300 (GRS190) is known for (2005–2010), 4 of them serious or costly. Each one says what to look for when you check the car, so you can spot it before you buy. Not every car has these faults: they are the ones worth checking on this model.
What to look for: Smell for petrol and look for fuel stains on top of the warm engine, and ask for the recall record.
Why it matters: The register describes high-stress areas created during pipe manufacture that, with fuel pressure pulsation and corrosive agents in fuel, may fracture over time. A high-pressure petrol leak in the engine bay is a fire risk and the car cannot be retailed until rectified.
Sources: 1
What to look for: Feel for a shaky idle at cold start, listen for a misfire, and check the OBD scan results for misfire codes.
Why it matters: The 4GR-FSE and 3GR-FSE inject fuel only directly into the cylinder, so nothing washes the intake valves; the retrieved workshop source ties misfire codes and rough running to that deposit build-up on IS250 and GS300 of this generation. Cleaning is a labour job on the intake side, which changes the buy price.
Sources: 1
What to look for: Listen for quick, even cranking on a cold start and a few hot restarts, and ask about any stalling or no-starts.
Why it matters: The register states the harness insulation has insufficient flexibility, the internal connector can move, wear, and lose electrical contact, so the engine may not start or may stall while driving from loss of fuel pressure.
Sources: 1
What to look for: Check the brake fluid level, look for fluid wetness behind the master cylinder, and feel for a slowly sinking pedal.
Why it matters: The register explains the seal relies on polymers in Toyota brake fluid; with other fluids the rear seal can dry and curl, leaking fluid, dropping the level and gradually degrading braking performance.
Sources: 1
Got a question about a Lexus GS300 (GRS190)? Ask Credov: a noise, a warning light, a part or how to fix it.
On top of the faults above, every Credov inspection covers the basics: fuel smell, leaks or filler rust, engine oil leaks, power steering fluid leak, drive belt cracks or squeal, rust underneath: chassis and mounts, engine mounts, engine oil level and colour, coolant level, colour and leaks, head gasket failure signs, cold start: rattle, knock or smoke, rough or hunting idle, engine running hot on gauge, gearbox or diff oil leak, swapped gearbox without lvv and more.
Researched by Credov from manufacturer recalls and service bulletins, owner reports and workshop sources. Repair prices are typical ranges, not quotes. See also fault codes and repair costs.