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Discussion Starter · #1 ·
Has anyone noticed how long it takes for the high idle to drop with the 2.4. Is it normal for this little 4 banger to do that, I know it's winter and all but to me it's not cold enough for an engine to high idle for more than 10 mins ... Sat there waiting the idle to drop but nooooo.. so I idled the long way through the parking lot and finally towards the end it dropped.
 

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I have a 2011 and 2012 Chrysler 200, both with 2.4L. On a cold start they go to 2000 RPM briefly, and within about 5 seconds are down to about 800 RPM or less in Park. Something is wrong.
 
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I don't know the temps, but on my Compass's temp gauge, it usually needs to hit the first 1/4 mark before it comes of 'high' idle. I put 'high' as such because my WGE 2.4 only goes up to 1,100rpm and it sits there until it hits the previously mentioned mark.
My sister's Dart, with the Multi-Air 2.4, has also kept a high rpm with a long idle, even after a tune up and such. It's been going on since she's had it, from what I remember. Nearly 100,000 miles later, that Dart's still going strong, if not atleast decently.
 

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1966 Crown Coupe, 2016 200 S AWD, 1962 Lark Daytona V8.
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If this is the 2014 Cherokee, there have been some software updates that may improve cold start, remote start (cold), shift and 4WD (PTU) behavior. Having the latest and greatest software versions installed can vastly improve the ownership experience:

Font Parallel Screenshot Number Document


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Font Screenshot Number Document

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Discussion Starter · #6 ·

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Discussion Starter · #7 ·
-33c this morning .. the idle hangs around 1500rpm. did not get a chance to look at anything on the Jeep last night , had to work late, but was able to do some reading and found this info from another forum about this topic.

The engine bay and front grills on the Cherokee are designed and optimized for the bigger V6 engine, and when the smaller 2.4L is installed in there, there is too much airflow in the engine compartment, meaning the engine can't warm up as well and can't maintain optimal temp on the freeway.
To combat this, the engineers added active grill shutters that close when you approach freeway speeds and reduce airflow in the engine bay. This also helps with aerodynamics, but I believe it's 50/50 for engine temperature control and fuel efficiency.

This doesn't help you at slower speeds and when parked though, so intrinsically it takes longer for the 2.4L to warm up than the V6. It also takes longer for it to warm up than it would have taken, had the engine bay and grills been designed around the 2.4L engine instead of the V6, as is the case in the Renegade, which warms up considerably quicker with the same 2.4L engine. (my wife has a renegade, so I get to compare the two vehicles all the time)

Another factor that doesn't help the 2.4L is that it has 5.5qts of oil. That's a relatively large quantity of oil for a 4 cylinder engine, and all that oil needs to be warmed up too.

It takes considerably longer for the oil temp gauge to get to halfway than it does for the coolant gauge...


Let me know what you think, I can see some of that being true to some extent but I would have to say that there are other factors involved with this High idle.
 

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These factors are insignificant.
And the author neglects the fact that engines with smaller masses will inherently warm up faster than larger ones. And the 2.4L engine in my car takes 5.0 qts of oil, not 5.5, and 1/2 qt is also irrelevant to warmup. My car is fully warm in 30-degree temperatures in less than 2 miles of driving.
 
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1966 Crown Coupe, 2016 200 S AWD, 1962 Lark Daytona V8.
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I disagree with the purpose of the grille shutters. It won't really have any affect on core engine temperature. Diesels use them because the diesel engines rely on combustion heat more than gasoline engines.
They close off at higher speeds, not to maintain engine temperature, but more to reduce aerodynamic drag and improve fuel economy:

In addition to the thermostat rationality P0128 fault, there is a bulletin about a thermostat housing issue. Use the housing that is marked 'INZI' as shown below.

There is a software update for the HVAC controller. It may not improve heat output, but may improve display accuracy.

Do you have heated seats and steering wheel?

A floor heat airflow issue is addressed by replacing a floor duct.

A clarification of air door operation is addressed.


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Discussion Starter · #10 ·
This KL is a North edition .. has heated seats and steering wheel .. also I notice when starting it the rear defrost comes on too. Lots of draw when starting the Jeep in cold temps. And it takes 5 liters not 5.5, But with that said @ImperialCrown has given me lots of homework to do, so I'll be looking into the battery and any codes that may be there. Check on what is posted above by @ImperialCrown but also I'm going to look at if a winter front is a good idea and a Wolverine heating pad. We are coming to the worst part of our winter where temps stay below -30c (-22F) for close to 3 months (On average) and I've noticed how fast the fuel tank is disappearing with all this high idle... need to get to the bottom of this .. thanks for all your suggestions so far and I'll keep you posted to findings.
 

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This KL is a North edition .. has heated seats and steering wheel .. also I notice when starting it the rear defrost comes on too. Lots of draw when starting the Jeep in cold temps. And it takes 5 liters not 5.5, But with that said @ImperialCrown has given me lots of homework to do, so I'll be looking into the battery and any codes that may be there. Check on what is posted above by @ImperialCrown but also I'm going to look at if a winter front is a good idea and a Wolverine heating pad. We are coming to the worst part of our winter where temps stay below -30c (-22F) for close to 3 months (On average) and I've noticed how fast the fuel tank is disappearing with all this high idle... need to get to the bottom of this .. thanks for all your suggestions so far and I'll keep you posted to findings.
I think you can configure what accessories (heat, defrost, seats, wheel) come on with which type of start (all, remote) in the radio settings.
 
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Discussion Starter · #12 ·
I think you can configure what accessories (heat, defrost, seats, wheel) come on with which type of start (all, remote) in the radio settings.
Yes you are right but this is my wife's so she dictates what is used... ;) I do not change anything in fear of ... :ROFLMAO:
 

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Discussion Starter · #13 ·
Well we have gone over this jeep looking at all suggestions and everything looks normal, I'm thinking that this is the parameters set for this Jeep and how it deals with colder weather.
 
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