Engine surge at low speeds

[Keith J.]

I just bought a new 2024 Big Bend 2.3 Bronco and I've been experiencing a low speed/low RPM engine surge when coming to a stop. Happens cold or warm, sometimes worse than others. I noticed it after installing a Corsa cat back dual rear exit exhaust system. Prior to that I installed a Corsa catch can and cold air intake. I didn't notice it until after the exhaust was installed. Maybe it was there the whole time but I just couldn't hear it because the exhaust was so quiet? The vehicle doesn't lurch or anything like that, but the RPM will fluctuate only when braking such as coming to a stop. Just wondering if any of the aftermarket parts have caused this for any of you? No codes or check engine light, just annoying. Thanks for any input.

Sponsored

 

[JKal]

I noticed this during cold start in the break in period, but went away around 2k miles. Now on 5k miles still haven't felt it again.

 

[Keith J.]

Ok thanks! I’m hoping it’s just a break in/learning thing because it’s extremely annoying.

 

[KABQ]

Is it the AT? It is probably just the transmission downshifting.

 

[Keith J.]

Is it the AT? It is probably just the transmission downshifting.

Yes it is auto and I think you're right.

 

[dgorsett]

Put it in Sport mode, it will be exaggerated.

 

[Keith J.]

Put it in Sport mode, it will be exaggerated.

Really? If so, that sucks.

 

[dgorsett]

Really? If so, that sucks.

Well, just because in Sport the transmission has a more aggressive shift strategy both up and down.

 

[TXBronco1313]

7k on my Bronco and I’m starting to notice the same engine surge everyone is talking about. Did anyone figure out what is causing it or if there’s a fix? I have the 2.3 auto engine

 

[Alanp970]

I’ve got 21K miles and mine does it occasionally. I don’t think it’s just the transmission downshifting because mine will actually lurch forward slightly like I tapped the gas pedal. No engine or exhaust mods on mine. I may go months without it happening so I haven’t been concerned

 

[TXBronco1313]

I’ve got 21K miles and mine does it occasionally. I don’t think it’s just the transmission downshifting because mine will actually lurch forward slightly like I tapped the gas pedal. No engine or exhaust mods on mine. I may go months without it happening so I haven’t been concerned

Yep same here I don’t think it’s the transmission it might be the fuel pump but I’m not 100% sure. I’m glad at least I’m not the only one it’s happening to

 

[Keith J.]

I’ve got 21K miles and mine does it occasionally. I don’t think it’s just the transmission downshifting because mine will actually lurch forward slightly like I tapped the gas pedal. No engine or exhaust mods on mine. I may go months without it happening so I haven’t been concerned

As soon as I installed the Ford Performance tune on it everything cleared up, hasn't done it since. I'm thinking that it had something to do with the aftermarket cold air intake or the aftermarket exhaust.

 

[Keith J.]

7k on my Bronco and I’m starting to notice the same engine surge everyone is talking about. Did anyone figure out what is causing it or if there’s a fix? I have the 2.3 auto engine

Ford Performance tune took care of the issue on mine. Hasn't done it even once since installed.

 

[Area51BS]

Are you sure it’s not the adaptive tranny? Get it reset

 

[TXBronco1313]

Ford Performance tune took care of the issue on mine. Hasn't done it even once since installed.

Haven’t done a Ford performance tune and with all honesty I’m not sure what I need/what to do. Any help guiding me through that would be appreciated

Sponsored