Bassman 1 Posted October 29, 2007 My 405 (XU7) has been making a chattering noise under load for a while now and it has started to irritate me. I thought it was probably a consequence of wear (148k miles now), but I also changed the cambelt as this had 70k on it, this made no difference. I had to fill up today and the Shell garage I normally use had run out of 95 RON unleaded so I filled up with V-Power. This has seemed to make a difference and the chattering has stopped on all but the steepest hill near where I live, which if I floor it in 2nd the chattering returns and is obvious again, although probably not as bad as before. Bearing in mind that this car has a full motronic ECU with wasted spark ignition, so no dizzy to advance / retard. Is there anything I can do to try and prevent / minimise this happening with 95 RON? Would adjusting the cam belt (I believe the XU7 engine has some adjustment in the pulley) help? Thanks Rob Share this post Link to post Share on other sites
GTI6BOY 29 Posted October 30, 2007 i had the same problem with 17" wheels, gone back to 15s now and its gone Share this post Link to post Share on other sites
ALEX 98 1 Cars Posted October 30, 2007 (edited) Sounds like fueling is out, are the injectors clean? Not a good solution but might be worth trying some redex or something similar. Edited October 30, 2007 by ALEX Share this post Link to post Share on other sites
Bassman 1 Posted October 30, 2007 Sounds like fueling is out, are the injectors clean?Not a good solution but might be worth trying some redex or something similar. Good idea, I pass Halfrauds on the way home, so I can grab some redex and smoke the neighbours out tonight. Not sure about the state of the injectors, they haven't been touched in 12 years, so they could be under-performing. Share this post Link to post Share on other sites
