Cold start and light acceleration surging engine, or loping. Anyone else have this issue?

[ljinnc]

I have a 2025 Big Horn with the 3.0L Hurricane engine with 1400 miles. My problem is that the engine surges at cold start and also during light acceleration where it changes gears around 2k rpm it also surges. Does anyone know what the problem is or experienced this problem?

 

[jmr]

Mine maybe twice early on during startup would surge. It hasn't done that since and I'm at 3,700 miles.

 

[motomarc]

Yes when starting it revs to 1400 i think for 1 minute. Someone posted about it. Mine stumbles /surges during warm up or fast idle whatever they call it now. 5500 plus miles almost always remotely started.

 

[Brahmajoe]

I have a 2025 Big Horn with the 3.0L Hurricane engine with 1400 miles. My problem is that the engine surges at cold start and also during light acceleration where it changes gears around 2k rpm it also surges. Does anyone know what the problem is or experienced this problem?

I’ve been hearing about a computer flash update, unsure if you had it already. Do you know your build date?

 

[ljinnc]

I’ve been hearing about a computer flash update, unsure if you had it already. Do you know your build date?

I've not had any updates and the truck was built in August 2024

 

[ljinnc]

I've not had any updates and the truck was built in August 2024

I guess that I should mention that I stopped by the dealer and the service advisor said that it sounded like the fuel pump needs replacement

 

[2025Rebelguy]

I started watching for this and this morning on cold start my 2025 Rebel ran rough and seemed to misfire for the first 20-30 seconds (estimate).

 

[Brahmajoe]

I started watching for this and this morning on cold start my 2025 Rebel ran rough and seemed to misfire for the first 20-30 seconds (estimate).

You might be able to get your dealer to flash it, they usually wanna see a check engine but worth a shot, it’s a software update takes 10 mins

 

[2025Rebelguy]

You might be able to get your dealer to flash it, they usually wanna see a check engine but worth a shot, it’s a software update takes 10 mins

I haven't seen a CEL light... and the symptom list doesn't seem to indicate cold start misfiring.. I'll call my dealer and ask if any updates were done after the truck was built (Aug. 2024)

 

[Brahmajoe]

I haven't seen a CEL light... and the symptom list doesn't seem to indicate cold start misfiring.. I'll call my dealer and ask if any updates were done after the truck was built (Aug. 2024)

It’s cold start catalyst misfire, it’s under other updates at the bottom

 

[2025Rebelguy]

It’s cold start catalyst misfire, it’s under other updates at the bottom

thanks, I see that now...

 

[2025Rebelguy]

my dealer did the software update, it still seems to surge a bit but the audible misfire seems to be gone.

 

[Foogie]

I picked up mine on 24 October. It's an August 2024 build date. I had them flash it prior to my picking it up...somebody posted the TSB in this forum regarding CELs for misfires and I sent them that.