Q: Rough idle when cold

asked by on September 13, 2016

Hello there, thank you for asking about your 1997 BMW 760Li V-12. My car has 168,500 miles on it. It has a very rough idle when it’s cold and it stalls. After it’s warmed up it will delay and falter under light throttle. My check engine light never came on the first 12 times it did this. Do you know how I can fix this?

Check Engine Light is on Inspection $79.99 - $89.99 Get a Quote

Hello there, thank you for asking about your 1997 BMW 760Li. Your problem has many potential causes. It could be anything from a failed mass airflow sensor to a worn fuel pump. The first step is to retrieve the diagnostic trouble codes associated with the Check Engine Light. These codes serve as a starting point for any further diagnostics. I recommend having a professional, such as one from YourMechanic, diagnose your BMW by retrieving trouble codes.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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

What others are asking

Why is my engine making a knocking noise.1997 Saturn SL2

Hello. If you know that the timing chain is off then the engine should not run. If the timing is correct but the chain is loose due to other issues then that may be the knocking noise that you are...

location of CKP sens 1997 Nissan 4 cyl pickup

The crankshaft position sensor is on the left rear of engine

Transmission 2004 BMW X3

Hi there - this transmission (5L40E) has problems with valve body wear in higher mileage vehicles that can manifest itself in some of the behaviors you describe. This is due to hydraulic pressure not being high enough for complete, rapid...

Speed sensor p01443 code

Hello. The speed sensor is located on the left rear of the transmission. It should be accessible from the bottom of the transmission. The catalytic converters should not have to be moved in order to get to the sensor. Most...

Your mechanic come and replace oil for my BMW X5, but the car said the oil is below minimal, how to do that?

Hi Tony. Thanks for contacting us today. Sometimes directly after the oil is changed, the oil warning light will illuminate. If it does not clear up within the next day or so, then I would recommend adding one quart of...

coolant leaking from under car

Hello. A coolant leak can come from a number of places under the hood. Typically, if it just started smoking all of a sudden, it is because a hose failed or the water pump is leaking. I typically get...

When I poor coolant into my BMW radiator it emptys right away and there is no leaks

If you keep pouring in coolant and it is disappearing without any external leaks after two gallons of coolant then you have an engine problem or heater core is leaking into the a/c housing. Check inside car to see if...

Need to replace thermostat or thermostat.

I would agree with that mechanic, but it could also be low on coolant. I would check the level make sure its full, and then start it up, have a certified mechanic such as one from YourMechanic, feel the upper...

Engine clanking when starting

Hello. Most of the lights will flash or come on when the car is started. It is the manufacturers way of allowing the owner to easily determine if the bulbs are working properly. If the lights remain on after a...

Related articles

How Does a Radiator Keep an Engine Cool?
Car radiators cool off your engine and prevent your engine from overheating. Coolant absorbs engine heat and dissipates it through the radiator.
How Long Does an Exhaust Gas Recirculation (EGR) Tube Last?
The The exhaust gas recirculation (EGR) tube is part of your vehicle's EGR (exhaust gas recirculation) system and is part of the EGR valve. The EGR valve works to recirculate the exhaust gas your car produces so that you aren't...
How Long Does an Ambient Temperature Sensor (Switch) Last?
In In many late-model vehicles, the need to manually adjust heat and air conditioning has been eliminated. You can actually set your car’s computer to regulate the cooling and heating process based on the temperature at which you feel most...