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Discussion Starter · #1 ·
Temperatures are slowly dropping here and I noticing that when it's 10C (50F) or less, the cold idle is not so smooth.
In the first few seconds after start up I can ear a few misses or pops and once the idles drops to the normal speed it 'bounces' around between two speeds not too far apart.
As soon as I hit the gas or get going, all is back to normal with a smooth idle.

-I get no codes associated with misfires.
-I also checked and cleaned the MAF sensor recently.

Any ideas ?
 

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How's your air filter? Quick, easy check.
 

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Check/clean the throttle body.
 

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How many miles on your vehicle? Are you due to have plugs replaced?

Another consideration is: Do you have any moisture buildup in your tank? Big swings in temperature especially when your car has a tank that’s low on fuel can create condensation buildup in the tank that can create drivability issues that most often are misdiagnosed as hardware issues. People will often throw a bunch of money trying to chase an issue that won’t resolve until you fix the fuel itself. To rule this out, I’d buy a yellow bottle of HEET fuel treatment / ‘dry gas’ which functions as a moisture dispersant, and add that to a fresh full tank of quality gas. If it’s a moisture issue, a $3 bottle of HEET will dramatically improve the situation almost immediately and should resolve it entirely over the course of a tankful, and might benefit from the same program for a second tankful just to be safe. If there’s no change, then at least you ruled out a very easy to address and cheap possible source of the problem and then it’s time to look at other sources and fixes.
 

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I think everyone mentioned that
-air filter
-spark plug (my guess)
-Throttle body
-any other issue aside the cold start?
 

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Discussion Starter · #6 ·
Thanks all for your tips.
Car is only 56k km (35k miles)

-Air filter was checked a few months back. Will check again.
-Throttle body; I will try cleaning it. If I remember from the video by Yuri (volvosweden on Youtube)I should have a new gasket ready. will try to get one.
-Spark plugs; does pulling one to inspect gives a good picture or should I check them all ?
-Fuel moisture; I poured a bottle of Heet last winter. Could try another one...
 

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Discussion Starter · #7 ·
Re-checked air filter last week end : like new.
Half a tank of Heet treated fuel since, no noticeable changes.
Still the plugs to check. Should I pull one or inspect all of them ?

This situation is directly linked to colder outside temperature...any other ideas ?
 

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Stef1 can you do a quick video of it?

Re-checked air filter last week end : like new.
Half a tank of Heet treated fuel since, no noticeable changes.
Still the plugs to check. Should I pull one or inspect all of them ?

This situation is directly linked to colder outside temperature...any other ideas ?
 

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Discussion Starter · #9 ·
On this video you can see the tachometer fluctuate but it's hard to hear the 2-3 misses...


I'll try to make a better one today.
 
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