Why the car won’t start, the engine knocks or a warning light is on
Symptom-based diagnosis: pick what is happening, answer two questions, and see the likely causes from simple to complex, what you can check yourself, and whether you can keep driving.
The answers highlight the matching cause in the list. The AI cannot see the car, so it gives likely causes, not a diagnosis.
- 1Low fuel, or the fuel gauge is wrong
- 2Plugs flooded after several attempts in the cold
- 3Fuel pump not switching on
- 4Faulty crankshaft position sensor or ignition system
- Check how much fuel there is – do not trust the needle alone
- Listen whether the pump hums when the ignition is switched on
- After many attempts, wait a while and try again
Prompt sent to the chat: «Help me work out what is wrong with my car: the starter cranks, but the engine won’t start. Suggest the likely causes from simple to complex, what I can check myself, and when to go to a service or call a tow truck. Car: [make, model, year, petrol or diesel], mileage: [km].»
You can send the chat a photo of the dashboard or a video with the sound – this works on the Starter plan too.
Work it out in the chatWhen you must not drive on
A red light means stop, a yellow one means check soon. Three cases where saving a few minutes costs the most.
Stop in a safe place and switch off the engine. Without oil pressure the engine can be ruined within minutes.
Stop and let the engine cool down. Do not open the hot expansion tank – the fluid is under pressure.
If the handbrake is off and the light is on, there may be too little brake fluid. Do not drive until you have checked.
What the dashboard warning lights mean
Twelve of the most common lights. Tap a light and the question about it goes into the form at the top. The symbols on your car may look slightly different.
Checking a car before you buy it: a checklist
Eight points to go through before you hand over the money. The AI will tailor the list to the model and mileage and suggest what to ask the seller.
- 1Documents and VINDoes the number match the documents and the body, how many owners.
- 2Body and gapsAre the gaps between panels even, any signs of repair.
- 3Paint thicknessA paint gauge will show repainted panels.
- 4Engine when coldAsk the seller not to warm the car up before you arrive.
- 5Tyres and suspensionIs the wear even, any knocks over bumps.
- 6Interior and electricsWindows, air conditioning, heaters, all the lights at start-up.
- 7Test driveAcceleration, braking, gear changes, any odd noises.
- 8Scanner diagnosticsFault codes in the control units, including recently cleared ones.
Car assistant in the chat – free
Starter – 0 ₽
30 energy units. Symptom analysis, reading a dashboard light from a photo and a checklist before buying – all of these are text requests, and they are free. For frequent questions there is Lite at ₽690 (150 energy) and Basic at ₽990 (200 energy).
Frequently asked questions
Why won’t the car start if the battery is charged?
Common causes: the gearbox selector is not in P, the immobiliser does not recognise the key, the terminals are corroded, the starter is faulty, or there is no fuel supply. Choose what the starter does on the first screen – the list will narrow.
Why does the starter crank but the car won’t start?
Usually it is fuel or spark: little petrol, the pump is not switching on, the plugs are flooded after many attempts in the cold, or the crankshaft sensor is faulty. Listen whether the pump hums when the ignition is switched on.
Is a knock when cold dangerous?
If the knock goes away once the engine is warm, it is often the hydraulic lash adjusters, and it is not urgent. If it does not go away, the knock is metallic or dull, and the oil level is low, do not delay the service.
Why is the check engine light on?
There are many causes, from a fuel filler cap that is not closed properly to misfires and faulty sensors. A steady yellow light is a reason to read the codes with a scanner; a flashing one means reduce the load and do not delay the service.
What do the dashboard lights mean?
Red lights mean stop or check at once, yellow ones mean check soon, and green and blue ones only tell you that a function is on. Send a photo of the dashboard to the chat and the AI will tell you what the light is.
Will the AI replace a car service?
No. It cannot see or hear the car, so it names likely causes and suggests what you can check yourself. The mechanic makes the diagnosis, and if the red oil or temperature light is on, stop first.
Find out what is wrong with the car before you call a service
Choose a symptomTryChat is not affiliated with Microsoft Windows.