Q: Engine shakes at idle, burning smell, only in cold temperatures

asked by on

Most of my issues ONLY happen when it is cold outside. When idling, either in park or at a stop light, my car does the following: - Idles EXTREMELY rough. Makes knocking noise. - Low RPMs, sometimes RPMs bounce up and down. Feels like it is going to stall, but doesn't. - Burning smell coming from vents (only happens after about 10 minutes of driving). - When it's extremely cold outside, my check engine light will blink when idling rough and then stop once I accelerate.

Other symptoms that I've noticed year round, regardless of temperature: - Car vibrates when using power windows, using heat or AC, and turning lights on.

  • Jerks a little when changing gears

Today I had a full tune up, new PCV valve, new valve cover gasket, and new air filter. No improvements, but CEL is now off. Mechanic said I'll need new motor mounts (for vibration), but shaking at idle, burning smell, and jerkiness all remain. Any suggestions?

My car has 165000 miles.
My car has an automatic transmission.

Hi there. The vibration could be the engine mounts loose on your engine or transmission. The engine knocking noise could be the engine pinging as there is not enough fuel to burn and the cylinders are colder than normal. This is a normal condition, however, if the condition continues as the engine is warm, then the engine temperature sensor has failed. The smell of burning in the vents is the dust burning off the heater core as the heater is operated. This is similar to the heater in a house that burns off the dust on the heating element causing the burning smell. The cabin air filter could also be full of dust causing the burning smell too. If you need further assistance with the vibrations and smells, then seek out a professional, such as one from Your Mechanic, to help you.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Engine shakes at idle, burning smell, only in cold temperatures

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Hello, I have an I35 Infinity 2002. Car wouldn't go pass 40 and acted like it wanted to shut off. I parked the car and saw white smoke.

If your engine is smoking white and has the smell of oil, then check for any oil leaks that would be leaking onto the exhaust pipe and burning off. The white smoke is water burning in the chamber and getting...

Q: smashed bumper in front and hood alittle.

Have you noticed any symptoms so far while driving it? It could be unsafe depending on how severe it is, but I would really have to visually see it and check under the hood to make the call. You can...

Q: Throttle Cleaner left in throttle body and I drove off....

If the vehicle is not driving correct after paying for the services then I would recommend taking it back to them as soon as possible as they should take you in and ensure they fix any problems. Especially for a...

Related articles

Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...