Backfiring on downshift?

[MRV99]

A lot of manufactures are adding the burbles and pops on “high performance” variants of cars. The ///M3 does the same in sport+ And I believe have heard the AMG’s do the same

 

[RamseyF]

I dont get a lot of popping, when it does its mainly when I am in sport mode and in manual. when the revs are high as you let the engine sort of do the braking as you downshift. other than that its only occasional. The only difference I notice with premium is more pep. not much but its there. I dont get less or more exhaust popping with premium.

 

[wheelman55]

Another “could be”, make sure to take your foot completely off the gas pedal when using the engine brake. We used to call this a “lazy foot”.

FTO’s explanation is right on, if the throttle butterfly stays open on decel it’ll cause a pop from unburnt gas reaching the hot exhaust.

Have fun!

 

[mathman]

Another “could be”, make sure to take your foot completely off the gas pedal when using the engine brake. We used to call this a “lazy foot”.

FTO’s explanation is right on, if the throttle butterfly stays open on decel it’ll cause a pop from unburnt gas reaching the hot exhaust.

Have fun!

About this lazy foot: I was just doing a long descent (Ebbitts pass eastbound, descending into Markleeville. Steep windy descent, occasional flat/uphill sections). Was in second, rpm’s 3-4 k, occasional light breaking. But whenever I applied the accelerator (just staying in second. Rpm’s 3k or so no gas, then I’d apply light gas) I’d get the popping sounds described in this thread. After a while I got worried about the popping and switched from manual to sport mode — still some engine braking but much more brake pad breaking. But also all popping gone: sport mode on this descent would upshift almost as soon as I applied gas and would tend to downshift if I hit brakes.

Was I effectively doing a “lazy foot” when I wanted to speed up a bit? And if yes … is it a problem for the engine or just loud?

 

[wheelman55]

About this lazy foot: I was just doing a long descent (Ebbitts pass eastbound, descending into Markleeville. Steep windy descent, occasional flat/uphill sections). Was in second, rpm’s 3-4 k, occasional light breaking. But whenever I applied the accelerator (just staying in second. Rpm’s 3k or so no gas, then I’d apply light gas) I’d get the popping sounds described in this thread. After a while I got worried about the popping and switched from manual to sport mode — still some engine braking but much more brake pad breaking. But also all popping gone: sport mode on this descent would upshift almost as soon as I applied gas and would tend to downshift if I hit brakes.

Was I effectively doing a “lazy foot” when I wanted to speed up a bit? And if yes … is it a problem for the engine or just loud?

Mathman. The “lazy foot” that I referred to happens on deceleration if you don’t quite take all of the pressure off the gas pedal.

This was on two fuel injected Alfa’s that I own/owned. The fix was to adjust the air fuel mixture, usually making it a bit richer.

I don’t think that you can do this adjustment on the Raptor

You would need to figure out how to recreate the popping, then take your mechanic for a ride.

Maybe FTO has further light and knowledge to offer.

PS. At least in the Alfas the popping itself did no damage. The lean mixture though could cause some wear.

Good luck with your diagnosis and repost if you get a solution to add to the knowledge base.

Best.

 

[Keith88]

Gen3 does it here n there... wish it was standard in sport mode.