Boola 0 Posted June 2, 2004 Can anyone explain what the gurgling and occasional popping noise made from the exhaust on the overrun is? I had a VR6 golf and it made a similar type of noise and you hear Scoobies make it a lot. Cheers Chris Quote Share this post Link to post Share on other sites
VR6 0 Posted June 2, 2004 Overfueling meaning that unburnt fuel hits the hot exhaust, which is why it should only happen when the car is warm. Quote Share this post Link to post Share on other sites
Boola 0 Posted June 2, 2004 So is it a problem? I didn't think it was. Quote Share this post Link to post Share on other sites
Nick_Micouris 0 Posted June 2, 2004 Mine is doing it at the moment but I think that is because my downpipe is leaking Quote Share this post Link to post Share on other sites
Boola 0 Posted June 2, 2004 I have to say that I don't think it only happens when its hot. Also my golf made similar sounds. I hear lots of sports cars making the same type of sound and I don't think it has anything to do with a leaky downpipe. Does anyone have any other ideas? Quote Share this post Link to post Share on other sites
Nick_Micouris 0 Posted June 2, 2004 The reason I mention the leaking downpipe is that the leak is before the lambda sensor and therefore the lambda probe is relaying an incorrect fuel mixture leading to an overrich mixture, hence the unburnt fuel. I am going by what my stealer told me on this one. Quote Share this post Link to post Share on other sites
PhatVR6 0 Posted June 2, 2004 yep, mine burbles, pops, and overfuels, becasue my home made downpipe leaks like a sieve. Quote Share this post Link to post Share on other sites
Nick_Micouris 0 Posted June 2, 2004 http://the-corrado.net/.archive/forum/viewtopic. ... t=burbling this may shed some more light Quote Share this post Link to post Share on other sites
crazymarcel 0 Posted June 2, 2004 My car does this, think it always has, i dont worry about it. A lot of Nova/ Corsa drivers would pay for an exhaust that burbles and pops all the time. Quote Share this post Link to post Share on other sites
Chaos 0 Posted June 2, 2004 Overfueling meaning that unburnt fuel hits the hot exhaust, which is why it should only happen when the car is warm. ive got a pulsar gtir atm and it pops and bangs all the time, including from dead cold Quote Share this post Link to post Share on other sites
VR6 0 Posted June 2, 2004 Overfueling meaning that unburnt fuel hits the hot exhaust, which is why it should only happen when the car is warm. ive got a pulsar gtir atm and it pops and bangs all the time, including from dead cold That's why I said should ;) Something must be hot enough to be igniting the fuel though :?: Quote Share this post Link to post Share on other sites
Chaos 0 Posted June 3, 2004 true. but i can get up on a cold morning and drive down the road i will literally get big pops an bangs within 50 yds or so ive seen the light anyways ;) and the pulsar is hopefully going on saturday and then its time to seriously start looking for a vr6 corrado Quote Share this post Link to post Share on other sites
Boola 0 Posted June 3, 2004 Thanks for all the replies everyone. Last night I was walking home when a new Porsche turbo passed me slowing down with lots of rude gurgling noises coming from the exhaust. If a new turbo does it then I'm not worried about my Corrado doing it!!!! Quote Share this post Link to post Share on other sites
Kevin Bacon 5 Posted June 4, 2004 I had an interesting chat with Vince about this and the VR head in general today. I learned that the back 3 cylinders are the hottest running ones and the exhaust valves in these 3 almost glow red when going for it. This is why the valves and seats start pitting at around 30K and by 100K, they're pretty well past it but because at full throttle the valve train is moving so fast and so much air is being sucked in, you don't really notice it. It's on part throttle and midrange acceleration you notice it the most. I did notice a massive improvement in general smoothness and low and midspeed pull after my head was done, I have to say. So anyway, if your VR is popping really badly on overrun, you might have badly pitted valve seats. But other things such as leaky exhausts, leaky injectors, dead O2 sensor and free flow exhausts can also cause it. Quote Share this post Link to post Share on other sites
Scott 0 Posted June 4, 2004 Mine pops on the overrun a little - but its more of a burble.... and only when hot.... interesting info there Kev - will be checking out the exhaust valves when the engine comes apart... Quote Share this post Link to post Share on other sites
Kevin Bacon 5 Posted June 4, 2004 Yeah Vince's knowledge never ceases to amaze me. I learn something new everytime I call and visit Stealth! Quote Share this post Link to post Share on other sites
Nick_Micouris 0 Posted June 4, 2004 are these valves in the manifold or downpipe? Quote Share this post Link to post Share on other sites
Kevin Bacon 5 Posted June 4, 2004 No they're in the cylinder head dude......... Quote Share this post Link to post Share on other sites
Nick_Micouris 0 Posted June 4, 2004 sorry :-s I take it they are in the head, right? :oops: Quote Share this post Link to post Share on other sites
Nick_Micouris 0 Posted June 4, 2004 yeah - I am sorry was being very thick :lol: Quote Share this post Link to post Share on other sites
Kevin Bacon 5 Posted June 4, 2004 No worries :wink: Quote Share this post Link to post Share on other sites
Bojmobile 0 Posted June 4, 2004 My vavler suffers from this all the time - I think it sounds SPORRRRRRRRRTY! :wink: Quote Share this post Link to post Share on other sites
