Question for new 4XE owners, is this normal?

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Stale

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It’s an intentional strategy that runs the secondary air pump and runs the engine rich and at high RPMs to accelerate heating the cats on cold start up. It’s pretty common across many makes/models, but FCA seems to make it especially obnoxious on many vehicles.
I didn't realize that this was even a thing, but googling/reading about it makes perfect sense with what I'm seeing. It definitely sounds like an electric compressor, stops around a minute after engine starting, though it's strange that it doesn't always happen. This morning was colder than it has been lately (~35 degrees), and it did not happen today; where-as last week it was doing this on 60 degree days (granted this difference is trivial compared to cat converter temperatures, but I would imagine that it should kick on during every cold start?)

Makes me wonder if either there's some complex logic that determines when this pump engages, or if perhaps there might just be an issue with it as to why it's occasionally so loud.

Service appt is set for Thursday, I'll talk to them about it just to be safe.





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bkinnj

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I didn't realize that this was even a thing, but googling/reading about it makes perfect sense with what I'm seeing. It definitely sounds like an electric compressor, stops around a minute after engine starting, though it's strange that it doesn't always happen. This morning was colder than it has been lately (~35 degrees), and it did not happen today; where-as last week it was doing this on 60 degree days (granted this difference is trivial compared to cat converter temperatures, but I would imagine that it should kick on during every cold start?)

Makes me wonder if either there's some complex logic that determines when this pump engages, or if perhaps there might just be an issue with it as to why it's occasionally so loud.

Service appt is set for Thursday, I'll talk to them about it just to be safe.
Very interested in what they say. It appears mine does this more when it's colder outside.
 

FirstF80InSpace

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I was at the dealership today for a test drive and cold started one. It was around 6 degrees celsius. No compressor sound at all.
 

Windshieldfarmer

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My 2.0l motor in my Recon has always been a bit noisy on start up....but not like OP’s. Thank would call that an EV driving incentive....
 

Dryver

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I didn't realize that this was even a thing, but googling/reading about it makes perfect sense with what I'm seeing. It definitely sounds like an electric compressor, stops around a minute after engine starting, though it's strange that it doesn't always happen. This morning was colder than it has been lately (~35 degrees), and it did not happen today; where-as last week it was doing this on 60 degree days (granted this difference is trivial compared to cat converter temperatures, but I would imagine that it should kick on during every cold start?)

Makes me wonder if either there's some complex logic that determines when this pump engages, or if perhaps there might just be an issue with it as to why it's occasionally so loud.

Service appt is set for Thursday, I'll talk to them about it just to be safe.
I thought about this some time after I posted my previous post about fuel tank pressure self-test. My son's 1997 Volvo GLT had a secondary air system, which is what brought it to my mind.
 
OP
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Just a quick update, so of course yesterday this sound was reoccuring *every* time I started the engine (even warm starts, which is something new), and today at the dealer it was silent... #MurphysLaw

Have a follow-up appt on Monday morning to try again, as I'm not willing to leave it there just yet.
 

JustinWPI11

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Just picked up our 4xe today and this was happening. Didn’t happen at first but driving the rest of the day it did at each start up. It was pretty cold here though. Please keep us posted.
 

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Just a quick update, so of course yesterday this sound was reoccuring *every* time I started the engine (even warm starts, which is something new), and today at the dealer it was silent... #MurphysLaw

Have a follow-up appt on Monday morning to try again, as I'm not willing to leave it there just yet.
Hi @Stale,

At this time, are you working with a Jeep Wave Specialist alongside your dealer? If not, please send us a private message with your VIN, mileage, and dealer so that we can provide additional support while in service for this.

Darlene
Jeep Cares
 
OP
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Took it in again today, this time it cooperated and made the noises. Dealer agreed it sounded different, and also agreed on the description of a compressor-type sound (ie, not engine itself). They happened to have another 4xe on the lot which they checked, and it too made similar sounds.

Though with no true mechanical issue (ie, nothing actually broken) & another vehicle with similar sounds, we're going to give it some time to see what (if anything) happens. We decided to have another look at it during it's first service, at which point we should know if it's getting worse or not (and there might be some additional information out there from more vehicles on the road).
 

Jehovasfitness

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That's a super annoying sound upon startup, especially for those that have a garage. On top of that everyone will look thinking your Jeep is about to blow
 

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Just picked mine up today, and went out to sit for a bit in it and play with the radio. And I also got this sound when I started up. I remembered this post. So please keep us posted as to what you find out.
 

JustinWPI11

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For what’s it’s worth. I had this Day 1 after we picked it up. Been driving it a week plus and haven’t heard it again. Also didn’t seem to be quite as load as the original posters. But please keep updating this page as it seems there are several of us that have experienced this.
 

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I experienced something like this yesterday. I was in my garage with the top and windows all open. At first I thought the engine was running. It sounded possibly like cavitation or an unbalanced fan.

I turned off the AC and it went away. When I turned the AC back on, I could hear it but not as loud as it had been.

The next startup, it did the same thing but also there was a very high fan speed for about 20 seconds.

Another time the fan ran high for a bit once I had it on the charger in my garage. I figured that was climate control cooling off the battery.

With an engine running I may have not noticed any of those sounds typically.
 

michail

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Reading through some of the other posts here made me think some more. The sound reminded me of the noise an AC compressor will make when there is a brief power outage.
 

Newbie 4xe

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The loud noise kicked in maybe 5 or 6 times for me so far in my five weeks of ownership and 1,275 miles (260 hybrid, 1,015 electric, 1/8 tank of gas remaining from dealership fill-up). I plug in all the time and I don’t experience this on startup. It has kicked on a few times (but not always) when my battery was running lower, but not always under 1%.

I have not used the AC yet so my issue isn’t related to the compressor.

I have noticed that when I hear the loud motor noise, the rpm stays at around 2k. The last time it happened I accelerated, but was still running on battery so the rpms stayed at the same level.

Isn’t there a small secondary motor that kicks in to make sure the battery doesn’t run too low? Maybe this is the motor that is making a very loud noise?

Please do let us know what you find. My 4xe doesn’t exhibit this problem regularly enough to take it to the delearship to diagnose.
 

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