Rory 0 Posted July 20, 2003 Driving home last night noticed my engine was making a clacking noise in time with the revs. After inspection this morning (and a near heart attack thinking it was the water pump) it truns out the centre spark plug in rear bank of cylinders was bobbling up and down and it was loose :shock: . I then took the offending HT lead off and the engine misfired when started. It seems as though even though the plug was loose, there was still ignition of the fuel. I tightened the plug and now the noise is gone :? . Is this a symptom of something more sinister? Or should i just ignore it? Quote Share this post Link to post Share on other sites
spoier 0 Posted July 20, 2003 Do you use a torque wrench on your spark plugs? You should. Were the threads dirty at all? You will get false torque values. Also plug threads should have a tiny drop of oil put on them when you put them in (with all aluminium heads - I assume the VR6 has alum head? I have a G60 :D) to prevent binding/galling from dissimilar metals Hopefully the plug hole isn't stripped. If it is you may be able to use an insert such as a helicoil to repair it without taking the head off... Skye Quote Share this post Link to post Share on other sites
Ice White Socks 0 Posted July 20, 2003 I bough my new storm last Sat- Perfect apart from a knocking noise like yours. Took it down to a VW specialist to get it checked out before buying it & the plug had come loose by about one and a half turns. The mechanic who tightened it back up said they have very long threads and it was unlikely to have caused any damage. I wouldn't worry about it. saying that the radiator blew up five days later :( :( . Bugger. Quote Share this post Link to post Share on other sites
dr_mat 0 Posted July 20, 2003 Same thing happened to mine, but I'm sure it "came loose" progressively after a service, cos I didn't notice it for some time. Once it got bad enough that I noticed the noise, I too had all kinds of thoughts about what it might be... The water pump was one of the most obvious. Anyway, cutting the long story short I finally found the loose plug (middle of the front bank), got it tightened up, and the engine has been fine since then. (Touching wood...) It surprised me how little impact on the driveability it had too - I had barely noticed the drop in performance and the tickover was not noticeably worse either. Matt. Quote Share this post Link to post Share on other sites
spoier 0 Posted July 21, 2003 It surprised me how little impact on the driveability it had too - I had barely noticed the drop in performance and the tickover was not noticeably worse either. ECU's are coool 8) It's amazing how much they can compensate Skye Quote Share this post Link to post Share on other sites
Kevin Bacon 5 Posted July 21, 2003 There's no excuse for loose spark plugs. This is precisely why I do my own servicing. Grease monkeys on a 9 to 5 just don't give a damn and silly mistakes like that occur all too often. It won't affect the engine running until the last thread gives way and you see a spark plug fly through the bonnet!! Kev Quote Share this post Link to post Share on other sites
Scott 0 Posted July 21, 2003 My mate thought he had a noisy tappet until he found a loose spark plug.......... Quote Share this post Link to post Share on other sites
Rory 0 Posted July 21, 2003 Not as if the compression is really high to push the plug out. Could the heat generated in the engine expand the block and loosen the plug cos these engines do run hot? Quote Share this post Link to post Share on other sites
sc16v 0 Posted July 21, 2003 Combination of the vibration of the engine causing the plug to come loose and the pressure in the cylinder helping it on its way. :D Quote Share this post Link to post Share on other sites
Rory 0 Posted July 21, 2003 Never had to buy a torque wrench before but as the block is aluminium im considering it :( Quote Share this post Link to post Share on other sites
spoier 0 Posted July 21, 2003 You don't even need an expensive "clicker" type torque wrench, even a simple deflection type or "bar" torque wrench are accurate enough for spark plugs If you do get a clicker, always dial the setting to zero when you put it away. It's a good idea to get it calibrated every couple of years as well. Skye Quote Share this post Link to post Share on other sites
CorradoVR6-Turbo 0 Posted July 31, 2003 There's no excuse for loose spark plugs. This is precisely why I do my own servicing. Grease monkeys on a 9 to 5 just don't give a damn and silly mistakes like that occur all too often. It won't affect the engine running until the last thread gives way and you see a spark plug fly through the bonnet!! Kev Im a mechanic...So i dont give a damn ? Quote Share this post Link to post Share on other sites
Kevin Bacon 5 Posted August 2, 2003 Im a mechanic...So i dont give a damn ? Sorry, didn't mean to offend anyone. I'm sure you do give a damn, but some mechanics don't and my comment was aimed at them. Kev Quote Share this post Link to post Share on other sites
