My car just randomly started misfiling, it starts good misfires when idling but at 60- 70 miles drives good. what could be the problem?
Nov 2, 2023 at 12:17 PM
Misfires when engine is idling?
2009 BMW 528I
KENGE1
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Hi,
Chances are, the misfire still is present at highway speeds. It isn't as noticeable because of the engine speed.
Has the check engine light turned on or started flashing while the engine is running? Also, often times a misfire is caused by an engine vacuum leak. If you haven't already, check to see if there are any disconnected or cracked vacuum hoses.
Here is a link that explains what to look for and how to check:
https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge
Let me know if anything is found, if the check engine light is on, or if you have other questions.
Take care,
Joe
Chances are, the misfire still is present at highway speeds. It isn't as noticeable because of the engine speed.
Has the check engine light turned on or started flashing while the engine is running? Also, often times a misfire is caused by an engine vacuum leak. If you haven't already, check to see if there are any disconnected or cracked vacuum hoses.
Here is a link that explains what to look for and how to check:
https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge
Let me know if anything is found, if the check engine light is on, or if you have other questions.
Take care,
Joe
Nov 2, 2023 at 1:10 PM
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