Pops and Bangs

[Steve-O 2007]

I have noticed with the hot weather my car pops and bangs alot more. Eg if I accelerate hard, press the clutch in and then blip / flick the throttle a little I get some very loud bangs (Sounds like a gun going off or a firework)

is this normal?

[StevenstonWullie]

my rev3 tubby does it all the time , pretty normal i think

[Martian_333]

Mine does this too (did) that was before it decided to transform into a large red kettle.

[Slarty]

It's because the exhaust is getting hotter due to the higher ambient temperatures.

Hot exhaust + over fueling on over run = burn inside the exaust/pops and bangs.

[Steve-O 2007]

Im guessing their might be some flame's as well??

[raptor95GTS]

most car ECU's shut the injectors off on a closed throttle above 1500rpm so you get the pop and bangs when you re apply the throttle after the gear change or blip the throttle with the clutch down

[Dan88]

mine does exactly the same and i love it!!!

flames and the lot

if you drive it enough you can get it to pop on demand, ideal for scaring people!!

[Martian_333]

Yeah all good

The pops/bangs I found you easily get after a fairly long run on the motorway/dual carriageway, constant 70mph the exhaust gets nice and hot, then when you pull off and change gears you can almost predict the bang/pop.

Night time just look in the rear view mirror, sometimes you can see an orange glow under the spoiler

[Steve-O 2007]

I need to do some night time driving now then

[fuchsiasteve]

Yes mine pops and bangs on the overrun. MR2 Turbo engines drip some unburnt fuel in to the cylinders when you shut off the gas to keep the fuelling primed to prevent lag (not turbo) when you go back on the gas. The result is that the when the turbo gets warm this unburnt fuel ignites on the turbo veins and causes the pops. Mine never pops when cold.

Be warned though if its doing it under acceleration it is not good

[TheRoadWarrior]

Yes mine pops and bangs on the overrun. MR2 Turbo engines drip some unburnt fuel in to the cylinders when you shut off the gas to keep the fuelling primed to prevent lag (not turbo) when you go back on the gas. The result is that the when the turbo gets warm this unburnt fuel ignites on the turbo veins and causes the pops. Mine never pops when cold.

Be warned though if its doing it under acceleration it is not good

All gasoline engines put some fuel into the cylinders on a closed throttle to help keep the cylinders cool, the ecu isnt doing it to reduce any kind of lag afaik.

[raptor95GTS]

Yes mine pops and bangs on the overrun. MR2 Turbo engines drip some unburnt fuel in to the cylinders when you shut off the gas to keep the fuelling primed to prevent lag (not turbo) when you go back on the gas. The result is that the when the turbo gets warm this unburnt fuel ignites on the turbo veins and causes the pops. Mine never pops when cold.

Be warned though if its doing it under acceleration it is not good

All gasoline engines put some fuel into the cylinders on a closed throttle to help keep the cylinders cool, the ecu isnt doing it to reduce any kind of lag afaik.

actually for fuel economy most modern engines on a closed throttle above 1500rpm do not inject any fuel.