2010 Buick Lucerne rough idle

[Wardonkey]

I own a 2010 buick lucerne with 54,000 miles on it. Recently and only when the car has sat outside in negative wind chill temps the engine will roar and feel like it's lagging when accelerating. And it will idle rough and will do this even at operating temp. But if I garage it, and then run it, it's fine. I'm clueless as to what this could be and if any of you have any thoughts on this I would like to hear them.

 

[Wrenchturner44]

I am assuming that you also are not getting a check engine light or any fault codes? If not, I would start checking some simple things. Is your air filter clean and air box / air cleaner sealed correctly. MAP sensors can be slow to respond if there are leaks with ambient cold air inadvertently entering the intake stream. Check also any EGR, PCV, and EVAP systems and controls. If your car has a fuel filter when was it last changed? Cold fuel (more dense) can flow slower through a dirty filter. Try switching fuel providers or adding some gas treatment to the fuel to properly rid any possible water contamination.

 

[Wardonkey]

I am assuming that you also are not getting a check engine light or any fault codes? If not, I would start checking some simple things. Is your air filter clean and air box / air cleaner sealed correctly. MAP sensors can be slow to respond if there are leaks with ambient cold air inadvertently entering the intake stream. Check also any EGR, PCV, and EVAP systems and controls. If your car has a fuel filter when was it last changed? Cold fuel (more dense) can flow slower through a dirty filter. Try switching fuel providers or adding some gas treatment to the fuel to properly rid any possible water contamination.

Correct...no check engine light. I'll check those things you mentioned.

 

[Lubener]

I would check fuel pressure and for vacuum leaks.. Then use a scan tool and post your live data, otherwise everyone is just guessing with your money. Fuel trims will tell a lot and give meaningful direction to pinpointing the problem..

 

[mk378]

When the engine revs up but the car doesn't go proportionally faster, it is a transmission issue. At least check the transmission fluid.

 

[incognito_2u]

I leaning towards a leaking air intake gasket.……..Scan tool with fuel trim PIDs will confirm.