HeMan Posted April 15, 2023 Share Posted April 15, 2023 Hello,I have noticed over the last few drives that the throttle pedal isn't very smooth on my 620S, which makes it tricky in traffic pulling away smoothly.I just disconnected the end of the cable and in isolation every part seems to move freely; the pedal, the cable and the thing on the engine end, they all move OK. But when I put it together, it is overly stiff, as if the cable is rubbing somewhere. Having listened carefully, the only sound which suggests friction, is at the engine end, and if I disconnect the pedal end it is still a bit jerky, which makes me think it is the engine end, where the wire inner cable comes out of the outer part.I considered a bit of lubrication, but my feeling is that it shouldn't rub in the first place, so this may not help and shouldn't really be needed. Or should I just put some 3-in-1 down the cable and hope for the best?My second question, is how do you get to it, as it is well and truly trapped below the inlet manifold above and supercharger pipework below! I can just about get a finger or two to it from the sides and there seems to be a black, square nut on it (see pic below, taken through the inlet manifold), but I can't seem to move it and don't know how it all goes together.Any help and advice would be much appreciated?P.s. I should add, the car is only 3 years old, so there are no signs of fraying or corrosion, every part still looks like new.Thanks Link to comment Share on other sites More sharing options...
Amos91 Posted April 15, 2023 Share Posted April 15, 2023 Mine went stiff after a track day, with the same diagnosis as you. Think my cable was old stock so the lube was dry.I bought a cable lubricator tool and some chain lube which forces the lube down the cable. It worked a treat and it has been lovely and light since. Link to comment Share on other sites More sharing options...
Hotfoot Posted April 15, 2023 Share Posted April 15, 2023 Is the cable close to the Exhaust headers? On my 420 the cable was routed quite close to the headers and it melted the rubber into the inner cable and made the throttle sticky and not smooth.Had to replace and reroute the cable higher up and used some heat shield sleeving. Link to comment Share on other sites More sharing options...
HeMan Posted April 16, 2023 Author Share Posted April 16, 2023 One of these you mean?You say you used chain lube, but the chain wax I have doesn't have the straw to connect to the nozzle and as I understand it the above tool only works if the can has the straw nozzle? The only thing I have with a straw that is close is the ubiquitous WD40, which I guess will do the job, but might not last as long as a heavier chain lube?Fortunately, on the 620S the routing of the cable is around the back and down the 'cold' side of the engine, so although I'm sure it gets hot, it shouldn't be anything like exhaust manifold hot. Link to comment Share on other sites More sharing options...
Amos91 Posted April 16, 2023 Share Posted April 16, 2023 Yes that's what I used. Then bought some wd-40 chain lube. I wouldnt use standard wd-40 as that will work very short term but it will probably displace the existing grease. Link to comment Share on other sites More sharing options...
HeMan Posted May 17, 2023 Author Share Posted May 17, 2023 Just wanted to follow up with this... I squirted some normal WD40 in by hand and that improved things, but I was concerned it would quickly evaporate or burn off.So I got some of this for £7:https://www.amazon.co.uk/dp/B00KMRDEMWAnd one of these for £8:https://www.amazon.co.uk/dp/B004LY3GDOMy first problem is that on my 620S the top (pedal) end of the cable has a plastic thingie attached for it to clip on to the pedal box hole. It seems odd that the plastic thing is fixed to the cable; there is no reason why it needs to be fixed on and it would make the cable very car-specific, but pull as I might it won't come off! This means you can't get the above tool clipped on to it!!! As mentioned above, I can't work out how to liberate the bottom end of the cable from behind the inlet manifold. But in the end I worked out I could just about get the above tool clamped on to the bottom end of the cable with the cable in situ, using feel alone, and then pass the tube of the spray grease between the inlet pipes and get it all plumbed in. A few squirts later, with plenty of rag held around to catch overspill, and I have a properly lubricated cable, with grease coming out of the top end, which must mean it is spread throughout the whole cable.Anyway, hope that helps someone sometime... Link to comment Share on other sites More sharing options...
7 wonders of the world Posted May 21, 2023 Share Posted May 21, 2023 Finishline MTB wet chain lube, drip it onto the exposed inner and let it run through, if there's a low loop then disconnect the pedal end first, few drops at a time and leave it a while, repeat until it emerges from he other end Link to comment Share on other sites More sharing options...
jbcollier Posted May 22, 2023 Share Posted May 22, 2023 Lube may well help, but, a properly made cable will have a Teflon liner and not need lubrication. If it needs lubrication, this means it's time for a replacement and it will be toast soon. The motoring gods are sending you portends now so you don't end up shipwrecked later. Link to comment Share on other sites More sharing options...
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