why does exhausts pop

[carter]

driving home today and realised that my exhaust pops when changing up and don gear. i knows that is nothing to be worried about but curious as to why it does it.

 

[Andy_Mk3]

Is it a standard exhaust or aftermarket? A lot of aftermarket ones do it, just the unburnt fuel in the exhaust getting hot and going bang

 

[astranaut]

mine does it coming down the gears, i've learnt how to make mine do it when i want it to, i love it!!

 

[Astraguy09]

Its just unburnt fuel in the exhaust, not a bad little trick however could indicate (if its doing it too much) that your over fueling/spark is weak!

 

[turbojay]

my let does it all the time, but thats because im using a 3.8 bar fuel reg instead of a 3.5 so as said the unburnt fuel goes bang inside the hot exhaust

 

[carter]

its straight throught 3 inch exhaust to boxer backbox. i am running a fse boost valve and i do use a fair bit of fuel. got new plugs just waiting on leads

 

[Andy_Mk3]

its straight throught 3 inch exhaust to boxer backbox. i am running a fse boost valve

that'll explain why then

 

[carter]

sometimes wish it had a volume button though, can get annoying sometimes- maybe gettin old lol

 

[astranaut]

know what you mean, mine isnt majorly loud but the constant drone on the motorway ARRRGHH!!!

 

[turbojay]

get the fse boost valve off there mate, they are known for upping or lowering the fuel pressure as they are pants, it wouldnt surprise me if its running mega rich.

have you got a gauge on there???? do you know what pressure your running???

once more it may not be fuel and it may just be exhaust and you could be running lean which = melted pistons.

also what engine is it???? any mods to engine????

 

[corsa_evn]

my x20xev pops gearing down and when you let off but thats got a 4 branch and a 3.5 bar fuel reg from a v6 vectra, still have the cat in to, im scared if i remove the cat its going to get even louder as its got a sportex cat back system the middle box looks like a cherry bomb, louder + flames would result in more plod fines

 

[reidy22]

mines does it all the time foot on foot off cuming down the gears etc thats a 1.2 16v 55plate corsa

 

[Mark T]

Usually a sign the Throttle position sensor isn't showing Idle position and cutting the injectors.

 

[savage16v]

get the fse boost valve off there mate, they are known for upping or lowering the fuel pressure as they are pants, it wouldnt surprise me if its running mega rich.

have you got a gauge on there???? do you know what pressure your running???

once more it may not be fuel and it may just be exhaust and you could be running lean which = melted pistons.

also what engine is it???? any mods to engine????

Mine worked fine matey, had a gauge on it and kept checking the pressure was as it should be

 

[carter]

no gauge and dunno wht its running. its an 82bhp 1.4 8v jobby - astra si. it goes really quick up the revs for a 1.4 but feels like its laking in power when i hit 70ish but still goes to 110mph, someone told me it sounds likes its been cammed however, i aint had the rocker cover off yet to check. should i just get a big block? be easier wouldnt it. seen a c25xe engine on ebay in need of headgaskets.