Weird pop on lift off.. WTF?

MDUBZ · Post by **MDUBZ** » Fri Oct 12, 2018 5:00 pm

Any ideas, it sound's like someone putting their finger in their mouth and making that pop sound you do as a kid.. it only occurs on lift off if I'm in 3rd and rev between 2k and 3k and lift off i get a loud pop.

Its a 3.0si

Scooba_Steve · Post by **Scooba_Steve** » Fri Oct 12, 2018 5:10 pm

Enjoy it

Silverzedtom · Post by **Silverzedtom** » Fri Oct 12, 2018 5:27 pm

As above, part of the fun.

Some people even spend money making the pops louder, myself included

MDUBZ · Post by **MDUBZ** » Fri Oct 12, 2018 5:31 pm

No.. this isn't a good pop. It sounds like someone hitting a glockenspiel

skelters · Post by **skelters** » Fri Oct 12, 2018 8:03 pm

Might be worth trying to record it or get someone to record it for you.

buzyg · Post by **buzyg** » Fri Oct 12, 2018 8:17 pm

Where is it coming from. Exhaust, under the car, engine bay, glove box?

MDUBZ · Post by **MDUBZ** » Fri Oct 12, 2018 8:45 pm

Ok.. so....
home to pub 1 : pop
pub1 to curry: pop
Curry to pub 2 : pop
Pub2 to home: try as I might, i couldn't replicate.. nice little blast with a clio williams I stumbled across ( used to really want one of those and a rare sight now) road was too twisty to get past but good fun.

The pop was coming from my left and slightly behind, had a passenger from pub1 to Curry house and he couldn't pin point it, but it was coming from his right so fairly central. I checked the boot or the chubby hole for any loose items that could have been knocking but nothing.. Exhaust was burbling nicely... any way, if it happens again I'll record it. The answer seems to be drink and it goes away....

coupedan · Post by **coupedan** » Fri Oct 12, 2018 8:50 pm

Gonna go ahead and say.. is it more of a thud sound..?
If so, could be the diff input shaft.. the 3.0si has a common issue with the diff input shaft "sticks" when you slow down or set off in traffic creating a thud like noise?

MDUBZ · Post by **MDUBZ** » Fri Oct 12, 2018 8:56 pm

Thx, nope, there is no thud or a feeling of vibration or jolt as drive engages. It's still silky smooth - It was a fairly high pitched pop which sounded like it was coming from just to my left. It had us both head scratching. I'll go out for a play tomorrow to see if I can do it again and record it.

tomrdy · Post by **tomrdy** » Sat Oct 13, 2018 7:52 am

My first thought was "mad! enjoy it" but after reading your description, that sounds annoying AF!

My wild guess is that it could be something to do with the vacuum from the sound generator (assuming you have one). What specifically I have no idea but worth a look?

The sound generator hole into the cabin is in the left footwell. If you remove the passenger side panel under the glove box (I assume youre RHD), you will see a hole on the firewall - this is where the pipe from the sound gen goes to. Maybe something is going on in there?

If you can't find it let me know and I'll remove mine (i was going to remove it to do some new wiring next week but I can do it earlier if it helps you out).

MDUBZ · Post by **MDUBZ** » Sat Oct 13, 2018 10:52 am

thx, yeah, my fist thought was it might becoming from the sound generator i had a quick look at pub 1; I wondered if the air intake was split and the sound was passing through into the cabin.. but everything looked pretty good and i couldn't get it to do it when the car was static.

and yes it was as annoying AF, not just the sound but because i couldn't workout what was doing it

MDUBZ · Post by **MDUBZ** » Sat Oct 13, 2018 8:07 pm

no sign today...

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