2005 300 2.7 rough idle, stalls at stop
 

Hi everyone,

Hope maybe someone out there has a answer for this one. My sis-in-law has a 2005 300, 2.7 liter. 97,000 miles. Yesterday started to have a rough idle after driving and stalls sometimes at a stop.

Checked for faults, none stored and check engine light doesn't come on.

I did a battery reset to reset the throttle body and it made no difference at all.

Weird thing is that when it stalled, none of the dash warning lights came on. Turned the key off then back on and the warning lights came back up, and went off as usual when the car started.

Any ideas would be greatly appreciated!

Sorry my friend, but its a 2.7Litre. I'm a big DODGE/CHRYSLER/JEEP man myself but Dodge was terrible with the 2.7L. They are a nightmare. My dad's Intrepid with that same engine has the same problem, and if not mistaken, it as something to do with the pistons. Do some research. Best bet, get an engine swap done for a 3.5L. Hope thats helps.

I don't think it's a piston issue, it runs fine when driving, just at idle its terrible.

Do these engines have a idle air control valve?

Yes. Look for a vacuum leak. Another possibility might be a dirty throttle body.

After replacing the throttle body, which made no difference, I told sis-in-law to take to dealer, didn't want to spend anymore of her money on educated guesses. Dealer computer found the EGR valve faulty right away. So much for 350.00 Scan tools from tool dealer (over priced Matco tools!)! Just replace EGR valve this past summer too, failed within 5 months. Rockauto part, hopefully they will refund me.

I have done a lot of research concerning modern aluminum engines and I really cannot fault the 2.7L as far as design.

There are some things that must be understood about small high output engines of this type. They will NOT hold up if neglected.
A lot of people claim this engine is junk, but the same can be said for similar issue with VW, GM, Toyota and other small engines.
1st. RUN 100% SYNTHETIC OIL and change it on schedule. These engines run HOT and cook mineral oil causing sludge issues.
2nd. They are sensitive to poor quality FUEL. Here is a wake up call. 10% Ethanol gasoline is a piss poor quality gas.
It takes it's toll over time.

Look folks. Everyone compares apples to oranges.
The old cast iron block v8 and I6 engines that lasted for decades without problems are GONE. With gasoline running between $3-$4 a gallon we have to rely on cars with small displacement high output engines.
The 2.7l is about 165 cu.in and produces 200hp. That is amazing, but it is not without a price.
I bought my Sebring with a 2.7L so I could park our '04 Hemi Durango (hungry, hungry Hemi) that got 15mpg around town.
This Sebring is getting 23-24MPG around town and that makes me smile when I'm filling up the 12 gallon tank.
I was in tears filling up the 28 gallon Durango tank.