| Author | Message | ||
     James Feller Prolific User Username: james_feller Post Number: 212 Registered: 5-2008 |
well, all I can say is WOW, welcome back 320Mbrs...you have been sorely missed... if you have been following our threads on these rectification works for Turbo charged cars you will by now be familiar with the highs and lows we have expirenced. In my case, the car was alwasy mechanically good however the achielles heal to my intermittent turbo boosting was indeed my Knock sensors as highlighted today. While all the improvements that RT and I have done certainly made the car 'better' it was still really just a fast Mulsanne S.... Now, we have renewed the absolutely crappy connnections onto the original knock sensors. The 'female connections' not only were badly corroded they also literally fell apart when we were trying to clean them up. No problems, we have fitted new connections, easy no worries. We again took both knock sensors out and this time really cleaned them up and soaked them in RT's 'special' whatever it is..... So with the knock sensors bright and clean again, put back in, the new female connections plugged in, lagging and holding pins put back we took the car for a drive. We didnt bother for the first part of the journey putting the boost gauge on, we simply thought 'lets feel if it makes a difference'....hmmmm with a delicous whoosh the car took off....RT smiled and said, OK get the guage out. Guage on and it was easily registering 6psi or about 320mbars. We repeated this a dozen or so times. With absolute precision and response the car went straight to these pressures and simply took off! I am now excited to get on the open road tomorrow and explore the performance. Now if you remember my has factory TB so hoping that with open road i can see 3-3500rpms and get TB working.... The upshot to this is KNOCK SENSORS not only age and become corroded, they simply will not allow the car to perform on anything much over 160mbars or 2-3 psi. I was reasonably lucky I suupose in so much as the car sometimes would perform and the knock sensors would behave and 'leave the waste gate alone and shut' but most of the time they would in error due to their appauling condition give me base boost ONLY. The work that RT and I have done has certainly improved the reliablity of the electrical connections to the solenoids this is paramount and the new positioning of the solenoids is very benefical and I recommend this highly. The knock sensors on my car frankly, I believe they were a big reason for my missing BOOST!!! so clean them up!!! its very much worth it I assure you. J | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 2660 Registered: 4-2003 |
In case you are wondering what we are on about, here is the knock sensor from my Conti R last Sunday. See the corroded electrical connections. This was usually working but occasionally not. It is now working as it should at all times. James’ were far worse than this one, and to quote him his looked as if they had a hornet’s nest inside. Note that if either knock sensor has a bad connection then there will never be any more than the base boost of 162 mBar allowed by the controller. Below is a picture of the new type of plug now fitted to both James’ knock sensors. Not only is it sturdier than the original, it can be released by the push of a thumb rather than prying a fiddly spring from it groove using an instrument screwdriver to release it. That will save someone a good 30 minutes when unplugging it in the future and ensure that no damage is done. The prong at the bottom is an old one: note the corrosion. On mine I cleaned it up with corrosion reducer, but would prefer to solder a new one on like James should the opportunity arise. RT.   | ||
| Lluís Gimeno-Fabra Prolific User Username: lluís Post Number: 262 Registered: 8-2007 |
Gents, Nice to see progress... I will take a look at mine. Something must be too right with your cars, would you have a nice leakage all will be rust-protected and your cars would be performing as they should  . I allow myself a little break here on knock sensors: My car has been driving now with different potentiometer attenuations, believe it or not anything from 380 Mbar max boost (no transient) produces a "lag" effect below 2600rpm. In my opinion despite of the attenuation, there is simply not enough exhaust pressure below 2200 rpm to get the turbo spinning fast enough to feel any significant increase in boost. From 2500 however the extra shove of the 380-390MBar is really perceptible. Best regards, Lluís | ||
| James Feller Prolific User Username: james_feller Post Number: 214 Registered: 5-2008 |
god its good!!! no tickets thanks goodness but 380hp is welcomed back!! hoorah! and might I add, in nothing crass, just a handsome 22 year old Bentley...love these cars! Oh and just as an aside issue, I can confirm again that quite surprising GOOD and improved fuel efficinecy im getting now the turbo is working to capacity!! its just gets better!  lag Lluis....hmmm I get a bit, i was telling RT today that just prior to kickdown there is about a second or so waiting for the pressure to build and then whoosh! Im prepared to accept that though in this car. my newer cars no! yep we are having fun assume you still are Lluis. cheerio for now! J | ||
| Lluís Gimeno-Fabra Prolific User Username: lluís Post Number: 263 Registered: 8-2007 |
Hoi again, Oh yes, and going to Germany soon ;-) I did have some headaches with the MAF sensor, but they are more or less solved and still have the odd drop of oil in the garage floor, oh well. To finalise tune up, I am getting a new O2 sensor from Bosch and re check all those nasty temperature sensor connections as my cold idle is not what it should be. See you, Lluís | ||
| Lluís Gimeno-Fabra Prolific User Username: lluís Post Number: 272 Registered: 8-2007 |
Dear all, The 3200Km holiday went beautifully and included some high speed driving in Germany. I can report of a perfectly working boost system and of a working knock protection system, which is very conservative: after a traffic jam in 30°C in Zurich and a few hours highway driving it was clear that something was interfering with boost, my guess is the knock sensors, nothing wrong with it, but good to know. In Germany I could experiment with boost over 160 Km/h, it's indeed interesting, at 2600 rpm, pushing the accelerator pedal will kickdown the car into 3000 rpm, a couple of seconds later you clearly feel the wastergate close and the car gain magically momentum, traffic and competence made my restrain my speed below 200 Km/h, the fastest part being between Wiesdbaden and the Dutch border. Also it's good to be able to say that after having changed the coolant temperature sensor and air flow meter, I was surprised to get a fuel consumption of ca. 14l/100 average under very difficult driving conditions, including mountain roads, city and highway and a perfect cold and hot idle. Only head ache still is an odd dropping of rpm to 400-500 on hot idle after suddenly closing the throttle, I will double check the cleanliness of the ISCV and will order the genuine Bosch AFM (which I did not due due to lack of time), as well as change the O2 sensor, simply as a matter of maintenance. The car is very dirty in and out, so it needs a week of love, it behaved faultlessly. Best regards, Lluís | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 2674 Registered: 4-2003 |
Dear Lluís, Great to hear the good news. James complained today about my dirty Conti R after just 300km from Canberra. Yes, it needs cleaning often. Those cities you mention are at my heart. A blast from Zürich to Berlin is a treat, n'est pas ? More to come on our local progress with Turbo matters.... RT. | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 2675 Registered: 4-2003 |
ps: James was a little sulky coming to visit this afternoon in his mind-bendingly and stupidly-fast multi-stage BMW turbo with about 999km on the clock while some valet lackey polished his Bentley for him at a secret garage. Now, James, which machine do you REALLY prefer ? RT. | ||
| James Feller Prolific User Username: james_feller Post Number: 227 Registered: 5-2008 |
ho ho ho! RT! yes I was a bit sullen as I missed the Big Blue while it was away for a few days but they have done a superb job and you know what im like, I cannot stand my cars dirty. Got it back this morning and looking out over the 'flight deck' bonnet is like looking across the inky blue of Lake Lausanne, just supurb.....as for what I prefer, well depends on my mood but....well you know the answer to that.... Lluis, great to hear! I sooooo miss Europe and its autobahns....while you risked nothing more than yourself and perhapes a rogue 'ghost driver' at 200 + klms per hour, here in Aus while my cars have often 'somehow' "i dont know' "it wasnt me' do these speeds....my freedom is at risk....its go to gaol in Aus if you are caught doing as such by Officer Plod. My TB is still being dormant....its a volcano ready to go with a few RT tests and mods....and if I see that bloody fabulous BRG Green Label Conti R dirty again ill be forced to wash the bastard myself Richard. yep more Turbo news coming. J |
