Buchanan Automotive Posted 16April, 2017 Report Share Posted 16April, 2017 Hi Paul , the new Siemens injectors & the hydraulic adaptors for these 4.7 Euro spec 928S models we do not sell over the counter , this is critical because we have to make custom fuel rail straps to make sure the fuel rails are perfectly aligned with the new injectors & their hydraulic adaptors & as each 4.7S has been apart over the years & the fuel pipes at front & rear of the engine ( that connect to the floating fuel rails) are all bent either shorter or longer or just bent anywhere after the last 34 years We have to get the once floating old fuel rails aligned perfectly , this does not take 5 minutes & is critical to eliminate any possible fuel leakage into the future , because we are going from barbed fitting at each end to barb fitting at the rail & then to a push on hydraulic fitting that takes modern injector "O"ring seals to hydraulically connect to the new injectorsAnd yes we re use the old fuel rails , unless they are badly rusted internally We are there only Porsche specialists in the world to my knowledge that use NEW injectors of the correct impedance & poundage for these 4.7S Euro spec , where as the others available are just 2nd hand injectors from another car from the States ( I think they are from a Ford or something similar ) , but to my knowledge they are just ultra sonic cleaned 2nd hand injectors , I could be wrong but thats only what I have heard , I am happy to be corrected with the knowledge that the others are in fact NEW injectors After 40 years + working on Porsche sports cars , the one thing I refuse to do is to fit 2nd hand injectors , because of risk of fire ( leakage from there injector body ) at any time The very reason I / we insist on new injectors is we see on a regular basis ( at our independant Porsche workshop ) is 4.7 928S / 911 3.2 / 944 / 951 / 5.0L 982S & 928S4 with leaking / weeping fuel from old ( original ) Bosch injectors bodies , not from the top "O" seal , but from the crimped together bodies of the injectors , been seeing it for years , its a result of far too many heat cycles & one too many ultra sonic cleaning of the injectors in the past Note 1 } The new Siemens injectors that we use are not designed for any one car , they are a custom injector designed for a particular impedance & poundage & flow rate , that why we use them Note 2 } We test the air mass meters our selves during the diagnosing stage Note 3 } With these cars getting into the 34 + years and thousands of heat cycles we see more & more that the air mass meter to injection wiring harness female multi plug are just crumbling , same goes for the three pin female multi plug for the crank angle sensor & the 8 X 2 pin plugs for the 8 injectors , if these are falling to bits , they have to be repaired properly RegardsBruce BuchananBuchanan Automotive Link to comment Share on other sites More sharing options...
ANF Posted 4July, 2017 Author Report Share Posted 4July, 2017 My 928 was running way too lean, hence all my low down running issues, with this now fixed and an abundance of low end power I now suspect that my fuel usage will rise.... sort of a double edged sword.... Link to comment Share on other sites More sharing options...
ANF Posted 31July, 2017 Author Report Share Posted 31July, 2017 Odometer now functioning and I am somewhat surprised by my economy....200km in total, 40km city/ suburbia and 160km country roads/ highway on 24 litres equates to 12 litres per 100km! This is way better than I had thought possible I will keep checking.Update, with my car now running as it should with POWER everywhere, it has now returned vastly different economy numbers..... with a small amount of spirited non suburban driving and some suburban driving it returned the lovely figures of 18.5 litres per 100km. Yet to be seen what a long country drive will return, but for smiles vs $$ still Waaaaay in front Link to comment Share on other sites More sharing options...
KGB Posted 1August, 2017 Report Share Posted 1August, 2017 Well done. My initially quoted fuel consumption figures not only align with those of the Owner's Manual, but also other users, yelp! Link to comment Share on other sites More sharing options...
ANF Posted 3August, 2017 Author Report Share Posted 3August, 2017 It should come down when the novelty of listening to the glorious V8 on song subsides..... doubt very much that will ever happen... Link to comment Share on other sites More sharing options...
KGB Posted 3August, 2017 Report Share Posted 3August, 2017 If Redracn hears the word subsidies we're doomed.... Link to comment Share on other sites More sharing options...
ANF Posted 3August, 2017 Author Report Share Posted 3August, 2017 If Redracn hears the word subsidies we're doomed....Booked in for that eye test yet...... Link to comment Share on other sites More sharing options...
KGB Posted 4August, 2017 Report Share Posted 4August, 2017 What? I can't hear you.... Link to comment Share on other sites More sharing options...
ANF Posted 4August, 2017 Author Report Share Posted 4August, 2017 Link to comment Share on other sites More sharing options...
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