Why does the new Audi car shake during cold start?
3 Answers
The following are the reasons why a new Audi car shakes during cold start: 1. The engine temperature is too low, and the temperature of both fuel and lubricating oil is very low. During a cold start, a richer air-fuel mixture is required, which in turn demands higher ignition energy. If the spark plug gap is too large, or if the ignition coil and high-voltage coil are aged, it can lead to a decrease in ignition energy, causing the car to shake. 2. Uneven operation among cylinders causes engine shaking. In multi-cylinder engines, significant differences in ignition energy between cylinders, as well as varying degrees of wear in pistons and piston rings, can result in inconsistent compression ratios. This leads to uneven power output from the engine, causing shaking. 3. Incorrect air-fuel mixture ratio leads to shaking. During a cold start, if certain engine sensors or some sensor signals have large errors, the ECU may make incorrect judgments. This can result in errors in fuel injection timing and ignition timing control, leading to engine shaking.
I just switched to an Audi last year, and the new car shakes quite badly during cold starts. At first, I was a bit panicked, but later a friend told me it's normal, mainly because the engine oil viscosity is high during cold starts, leading to insufficient lubrication, and the low temperature requires the engine to warm up. The new car is still in the break-in period, and the parts haven't fully settled in yet. Occasional shaking isn't a big issue, and it might improve after driving a few more times. Check the engine oil level and cooling system to ensure there's no debris buildup, and use high-quality gasoline—avoid low-grade fuel. After starting, patiently wait a minute or two for the engine to warm up; once the idle stabilizes, it should be fine. If the shaking persists or worsens, take it to the dealership to check the spark plugs or sensors. Don’t ignore it—severe shaking can affect driving safety, especially in winter when temperatures are low. Don’t delay maintenance for a new car; getting early inspections can prevent future issues, saving you time and hassle.
As someone who loves delving into cars, I think the common causes of cold start shaking in new Audi vehicles lie in the ignition system and fuel control. During cold starts, the spark plugs haven't warmed up sufficiently, leading to uneven ignition. Coupled with possible momentary insufficient fuel supply from the injectors, this creates an imbalance in engine operation, resulting in shaking. Audi cars have numerous electronic units, and the software adjustments upon startup might be sluggish or misjudge temperature effects. It's advisable to use simple tools to check voltage and inspect the fuel injectors, ensuring the battery has enough charge to avoid weak starts. New cars have less carbon buildup, but frequent short city drives can lead to impurity accumulation, causing shaking. Regular highway driving to clear carbon deposits or using fuel additives can help alleviate this. The key is not to tamper with the car yourself; professional diagnostics are safer, and new cars usually come with free servicing during the warranty period. Before daily starts, wait for the engine preheat signal light to turn off before driving, and minimize frequent short trips to allow the engine to warm up properly.
