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tubbyG
23-03-2011, 21:36
I finally got a few little jobs finished today so I was able to take the 5 for a little drive:D, but there is still a couple of niggling problems.

when i shut off the ignition, about 2-3 seconds later a loudish pop comes from the exhaust (uncle buck style:eek:). any ideas?

Tony Walker
23-03-2011, 22:00
mine very rarely does that, hasnt done it for a long time tho. i think its when you switch it off a bit quick after stopping.

REBEL GT TURBO
23-03-2011, 22:13
When you shut down the engine you are stopping the spark to the plugs. You should not be backfiring when you hit the kill switch.

If there is carbon buildup on the piston, it can get "red hot" from long-term use, and it will ignite any fuel left in the cylinder regardless if there is spark. This would explain the backfire after a long day of running.

Take out the spark plug and shine a light down the hole. If the piston is black, you have carbon buildup. If it is metallic, it's something else. Carbon buildup can lead to detonation and yes, permanently damage your engine.

;)

Mart
23-03-2011, 22:30
Perfectly normal. No need to worry :agree:

Kris M
23-03-2011, 22:53
^^^^^^^ :agree:

Tony Walker
23-03-2011, 22:59
I too wouldnt worry about it.:agree:

tubbyG
23-03-2011, 23:06
When you shut down the engine you are stopping the spark to the plugs. You should not be backfiring when you hit the kill switch.

If there is carbon buildup on the piston, it can get "red hot" from long-term use, and it will ignite any fuel left in the cylinder regardless if there is spark. This would explain the backfire after a long day of running.

Take out the spark plug and shine a light down the hole. If the piston is black, you have carbon buildup. If it is metallic, it's something else. Carbon buildup can lead to detonation and yes, permanently damage your engine.

;)




thanks for the replys. The car has not really moved off the drive since before xmas due to me having no monies or time, the engine has been run up to temp every couple of weeks tho. I had a 285 cam put in last november, at the back of my mind i was thinking that the guy timed it in wrong ( it also wont idle alone below 1.5k - air leak at carb i think) but have no idea if that would even cause that ! when the head was off the top of the pistons looked ok, a slight build up of course but majority was cleaned off.

tubbyG
23-03-2011, 23:10
Perfectly normal. No need to worry :agree:


it never did it last year:confused:!!

but if its no big deal, I will put up with it for the time being till its all set up..........

Mart
24-03-2011, 04:55
All gtt's that I've owned, in various states of tune, have done it, but hey ho.

Alex
24-03-2011, 10:08
My GTT has never done this but my R11 did. I know of a other GTT's doing it, but as said, no need to worry. :)

markey b
24-03-2011, 10:51
my orange car does it :agree: