cheesey 0 Posted May 6, 2008 since setting the timing on the G its got a rattling noise like a loose bolt notices on even mild throttle is this pinking (someone said it was) none of my other car have sounded like this it was a completely different noise and very distingtive and sound nothing like it but all cars are different Quote Share this post Link to post Share on other sites
Supercharged 2 Posted May 6, 2008 Sounds like it... weather has got hotter since you set it up too most likely... Make sure you have a good tank of fuel and take a 13mm ratchet spanner out then keep testing and adjusting the timing until it stops pinking. Quote Share this post Link to post Share on other sites
cheesey 0 Posted May 6, 2008 just been out and it only makes the noise when you get to 2700/2800 revs even if im lightly accelerating but not always (is that when the boost starts coming in) is there anything on the boost side that could rattle like that Quote Share this post Link to post Share on other sites
Supercharged 2 Posted May 6, 2008 Pinking / pinging should be fairly high pitch - like marbles hitting each other... If it's not the above it could be an exhaust heatsheild - or the one at the bottom of the cat maybe?? Quote Share this post Link to post Share on other sites
cheesey 0 Posted May 6, 2008 sounds like a rattley bolt/nut from the drivers side some where if you rev the car standing still you cant hear it definately a rattle no cat Quote Share this post Link to post Share on other sites
Guest Posted May 6, 2008 strangely after reading this thread i went out for a blast in my G60 and guess what? looked in the engine bay when i got back, as since i have had this G60 its always "pinked" a little at certain revs (as my other G60 Rallye did awell mind :norty: ) and i looked at the knock sensor (down by rad fan) and its been unplugged :nono: god knows how long its been like that? but it must be a while as it has a nice layer of dirt and dust on it :eek: guess i could have knocked it off when doing the charger pipework last week? i think i have plugged it back in properly? but the loom seems very tight in that area, and the metal clip seems a bit of an angle? and its almost as hot as the face of the sun under there at the mo :grin: have to wait till it cools from its 25 mile 3 figure blatting :nuts: I dunno what effect if any this being plugged back in will have? but it ran fine without it :lol: it just had that tell tale pinking around the 1500 & 2800 rpm range, its only very slight and almost immediately clears passing that range, much more noticable when the ambient temp is high like today aswell Quote Share this post Link to post Share on other sites
paul20v 0 Posted May 6, 2008 Hi When unburned fuel/air mixture beyond the boundary of the flame front is heated and pressurized by the advancing flame front for a certain length of time, detonation occurs. It is caused by an instantaneous, explosive ignition of pockets of fuel/air mixture. The cylinder pressure rises sharply beyond its design limits, and if it is allowed to persist, detonation will damage or destroy engine parts. The deleterious mechanisms range from particle wear caused by moderate knocking, to holes punched through the piston or head caused by serious knocking. Detonation can be prevented by the use of a fuel with higher octane rating, richening the fuel/air ratio, reducing peak cylinder pressure by increasing the engine revolutions (e.g., shifting to a lower gear), decreasing the manifold pressure by reducing the throttle opening, or reducing the load on the engine. Because pressure and temperature are strongly linked, knock can also be attenuated by controlling peak combustion chamber temperatures at the engineering level by compression ratio reduction, exhaust gas recirculation, appropriate calibration of the engine's ignition timing schedule, and careful design of the engine's combustion chambers and cooling system. As an aftermarket solution, a water injection system can be employed to reduce combustion chamber peak temperatures and thus suppress detonation the knock sensors retard the timing stopping this so if there not connected ,connect them and if there not making any difference renew them . hope this all helps :) Quote Share this post Link to post Share on other sites
Guest Posted May 6, 2008 :eek: very usefull info, i have plugged the sensor back in properly for definate now, is there any definitive way of checking its operating as it should though? sorry for thread hijack :norty: Quote Share this post Link to post Share on other sites
paul20v 0 Posted May 6, 2008 :eek: very usefull info, i have plugged the sensor back in properly for definate now, is there any definitive way of checking its operating as it should though? sorry for thread hijack :norty: knock sensors are funny things and dont always show up on diagnostics if the car is pinking they are first port of call if basic timing checks out and you are not running rubbish fuel , also never over or under tighten them i think its 15nm off the top of my head but you would have to check. Quote Share this post Link to post Share on other sites
Guest Posted May 6, 2008 cool, cheers for the info, i will see what its like over the next few days, hopefully it will improve what was already running well :lol: might sling a new sensor on it anyway just to be on the safe side, think they quite cheap from vw anyway, im servicing it next week as its going to Normandy on hols with me, so plugs oil filters will all be done so i may as well do the sensor if needed, i can get it checked on vag com tommorow at my mates "vw" dealership :grin: Quote Share this post Link to post Share on other sites
paul20v 0 Posted May 6, 2008 have a good holiday :salute: Quote Share this post Link to post Share on other sites
boost monkey 0 Posted May 7, 2008 The deleterious mechanisms range from particle wear caused by moderate knocking, to holes punched through the piston or head caused by serious knocking. :scratch: Quote Share this post Link to post Share on other sites
cheesey 0 Posted May 7, 2008 just put a new knock sensor on vw (£ 51 got some new other wires they said i needed but didnt) still the same the old 1 was in tatters as for the noise i dont even accelerate hard and the knocks there same revs Quote Share this post Link to post Share on other sites
paul20v 0 Posted May 7, 2008 The deleterious mechanisms range from particle wear caused by moderate knocking, to holes punched through the piston or head caused by serious knocking. :scratch: i take it you mean the wonderful word '''Deleterious''' means harmful or injurous to health, hence the use of it in that sentence sorry. :) Quote Share this post Link to post Share on other sites
paul20v 0 Posted May 7, 2008 just put a new knock sensor on vw (£ 51 got some new other wires they said i needed but didnt) still the same the old 1 was in tatters as for the noise i dont even accelerate hard and the knocks there same revs if its pinking is your basic timing right , and did you torque the sensor to 15nm no more no less , it tends to be heavy loads more than hard acceleration in and around mid rev range generally , if not maybe the noise is something else what colour was the sensor as a lot of v a g engines have two , one blue plug , and one green plug. Quote Share this post Link to post Share on other sites
cheesey 0 Posted May 9, 2008 it was a blue 1 now green Quote Share this post Link to post Share on other sites
paul20v 0 Posted May 9, 2008 it was a blue 1 now green most of the cars i have had , use both i dont actually think theres a difference only the length of the wire. Quote Share this post Link to post Share on other sites