| Author | Message | ||
     Chris Browne Frequent User Username: chrisb Post Number: 72 Registered: 2-2010 |
Hello everyone, My wife and I were on our way down the motorway this morning when we had the misfortune of a failure to proceed on the M1. The car had been running faultlessly at 70 mph when the engine suddenly cut out with no warning. All gauges were reading normal and there were no warning lights. Once on the hard shoulder, I was able to restart the engine briefly only for it to cut out again. After several minutes, I started the engine again and this time, it ran for long enough to reach the next exit of the motorway but the engine cut out again as I reached a lay by. There is no misfire, once the engine restarts, but a sudden loss of power when the fault recurs. After the initial failure, each time the engine stopped, it was preceded by an electrical "buzzing" which sounds like a relay cycling on and off very quickly or possibly something arcing (but no smoke or smell) from the area in the dash behind the switchbox/warning light panel. The RAC attended after a 45 minute wait but were unable to find the fault. By this time, the engine had cooled so I asked if the RAC patrol would be prepare to follow me back home, on the motorway, in case the engine stopped again. He agreed to do this and despite the buzzing occuring three times and the engine faltering but not stopping on the journey, we were able to get back home safely. I do all my own maintenance on the car but am a little incapacitated at the moment with a bad back so will have to wait to start stripping the dash down until I am more mobile. In the meantime, I wonder if any of my fellow message boarders have any suggestions what might be wrong or have had a similar problem which might point me in the right direction? Thanks, as always, in anticipation, Kind regards, Chris | ||
| Nigel Johnson Frequent User Username: nigel_johnson Post Number: 61 Registered: 12-2008 |
Hi Chris, I'm wondering if there is a fault in the ignition switch barrel. Do you have a heavy bunch of keys? Regards, Nigel. | ||
| Nigel Johnson Frequent User Username: nigel_johnson Post Number: 62 Registered: 12-2008 |
Hi Chris, I've just done a search of this site. Ignition switch or switchbox. Try it! | ||
| David Gore Moderator Username: david_gore Post Number: 1061 Registered: 4-2003 |
Nigel - I am with you on your diagnosis. Chris, please try driving the car with just the ignition key in the switch and see what happens. An extended run down a rough road will be a good test. If the problem doesn't show itself, try driving the car over the same route with your normal set of keys. If the problem reoccurs with the full set of keys, you will need to remove the switch box and take it to a locksmith who deals in Yale locks and they can get the parts to refurbish the lock cylinder and plug. While the switch box is apart, check the rotary switch contacts for pitting/damage from the arcing that was responsible for your "buzzing". If the contacts are badly damaged, see your local auto electrician about refurbishing the contacts otherwise you may have to source a replacement new/used rotary switch as well. A timely reminder to all R-R/B drivers; it is not good practice to drive the car with a heavy set of keys in the switch as the lock cylinder/plug are prone to wear from the loads imposed by the jiggling mass of keys hanging off the cylinder. | ||
| Chris Browne Frequent User Username: chrisb Post Number: 73 Registered: 2-2010 |
Hello everyone, Thanks for your prompt replies. Unfortunately, the ignition key is the only key on a lightweight RR rubber key fob but it sounds to me as if your suggestions may have hit the mark. I can't vouch for the size of the bunch of keys used by the previous owner(s) so I may be experiencing a problem that has been a long time in the making. Thanks again to all and I will report back once I am a bit more mobile and can get stuck into the problem. Kind regards, Chris | ||
| Chris Browne Frequent User Username: chrisb Post Number: 74 Registered: 2-2010 |
Hello everyone, Here, as promised, is an update on my on going difficulty. I removed the switchbox from the dash and removed every wire and terminal to check them and also thoroughly cleaned the ignition switch contacts. I tested the car and the fault recurred after approximately the same mileage travelled. Today, I decided to fit a known good coil and also removed the switchbox from the dash but left it hanging from a cable tie. I took the car out and - surprise, surprise, the fault is still there. At least I am now sure the noise is not coming from the switchbox but from inside the dash board somewhere to the right of the steering column. I also know that it is not a faulty coil. The detective work continues but I now have to dismantle the knee roll and remove the side carpet to expose the wiring and sockets in the hope that whatever it is will show itself. Oh the joy of running a classic car! Kind regards, Chris | ||
| Nigel Johnson Frequent User Username: nigel_johnson Post Number: 64 Registered: 12-2008 |
Hmm, I've recently heard of a dry joint to the fuel pump relay causing such problems. But, thats on'tother side. Regards, Nigel. | ||
| Paul Yorke Grand Master Username: paul_yorke Post Number: 841 Registered: 6-2006 |
Hi Chris, When the car will not start, take the king lead out of the dizzy cap and place it near an earth ( bonnet catch bar) and check for a spark. Have you noticed if the engine fire once after you cranked it over on;y when you turn the ignition off? And carry a tin of carburettor cleaner with. When she cuts out, remove the distributor cap and spray on the ignition module inside the distributor ( to cool it down) then try starting the car again. If it starts immediately after spraying, that may be the problem. If you have a spark then you can try pulling the oil pressure switch wire off to see if that is cutting the fuel pumps. | ||
| Chris Browne Frequent User Username: chrisb Post Number: 75 Registered: 2-2010 |
Hello Nigel and Paul, Thanks for your suggestions. I am fairly sure it is not a fuel supply problem as the engine cuts out instantly with no misfire or spluttering. Sorry if it's me being dim Paul but I didn't understand your comment "Have you noticed if the engine fire once after you cranked it over on;y when you turn the ignition off?" Could you clarify please? I have also just discovered that the car was fitted with an after market Piranha alarm which has been removed but I wonder how well the wiring was removed or insulated (or not, as the case may be!) Would a problem with the ignition module produce the electrical buzzing that I hear behind the dash panel just before the engine cuts out? I am not sure if the buzzing is the root of the problem or is being caused by a failure elsewhere in the loom. The hunt continues. Kind regards, Chris | ||
| Paul Dabrowski Experienced User Username: shabbyshadow2 Post Number: 21 Registered: 9-2005 |
I had this problem before and i think i have solved it, but i have not been driving my Shadow 2 - SRH 35979 much over the last few months. I had a situation when at idle i hear a buzzing/relay sound from behind the speedo and saw the speedo needle jumping up and down. This was then followed by the engine cutting out and not restarting until it was left for 20 or so minutes. On the front of the engine there are I think 2 oil pressure sender units, one is wired through the fuel pump to cut the fuel off it the engine runs out of oil pressure to avoid further engine damage. I think from memory, I disconnected the lead of the middle sender unit and it has never cut out again. Any comments anyone? | ||
| Julian Moreno Experienced User Username: morenoj Post Number: 13 Registered: 5-2005 |
The same thing happened to me in a horrible situation so far of my home in Spain......exactly the same...I disconect the oil pressure sender to the relay and the car works.....waiting for a new one because the fuel pump always working with the engine stopped but ignition switch on..I think is dangerous, but for me was the problem solved.....I hope can help you | ||
| Chris Browne Frequent User Username: chrisb Post Number: 76 Registered: 2-2010 |
Thank you Paul and Julian for your experiences. I will certainly try disconnecting the pressure sender but I am leaning toward the fault being the ignition module in the distributor. Having spoken to an independant RR&B specialist, he tells me that the symptoms of the failure point to the ignition module breaking down. I will replace that also and hope that I can find the problem. Kind regards, Chris | ||
| Dave Burbidge Experienced User Username: ovation Post Number: 44 Registered: 8-2009 |
Chris we had the same problem on our 82 Spur. Weak or no spark from the distributor. Turned out to be the distributor module. We replaced it with a new coil and distributor from RA Chapman Melbourne.Its a great peice of kit and I swear the car runs better than ever. When replacing the distributor the old ballast must be removed or the problems will continue. Hope this helps. | ||
| Chris Browne Frequent User Username: chrisb Post Number: 77 Registered: 2-2010 |
Hello Dave, I will obtain a new ignition module next week and fit it. I'm a bit puzzled by your removing the ballast resistor. I was under the impression that the Opus ignition system has to have a ballast resistor in order to function correctly? Kind regards, Chris | ||
| Dave Burbidge Experienced User Username: ovation Post Number: 45 Registered: 8-2009 |
I had a local garage put in the new distributor and coil because I travel a lot for work and we have a wedding business on weekends. My car stopped running just after a wedding the next weekend and I had the car towed to my usual Rolls mechanic who removed the ballast and told me the new unit didn't need it . I also replaced the distributor on my 82 Mulsanne with the new unit and coil and we did the same procedure.Not a hint of trouble since. | ||
| Randy Roberson Experienced User Username: wascator Post Number: 34 Registered: 5-2009 |
Sounds as if the problem might be temperature-related. Sometimes a fault will not appear until the offending part reaches a certain elevated temperature, then Screech: you are down. If the Car is driven shorter distances most often, there may not be an opportunity for the part to reach a high enough temperature to bring the problem on. However, on a longer journey, the temp does rise to the point that the problem manifests.One sure sign: after letting things cool a while, the Car will restart and proceed for a distance. Since the Car is already somewhat warm unless cooled completely to ambient, the time to the next shutdown will be shorter, in inverse relation to the length of time things had to cool. Electronic parts like ignition controls can exhibit this behavior; do I recall reading, ignition coils will do this also? I hope this helps you figure it out. | ||
| Chris Browne Frequent User Username: chrisb Post Number: 79 Registered: 2-2010 |
Hello Randy and everyone, Thanks for your comments. Here as promised is a further update on my "failure to proceed". I have now discovered that the chattering noise is indeed a relay and it is the fuel pump relay which is cycling very rapidly, so much so that the base plate gets too hot to touch. I removed the relay and took the cover off expecting to find damage to the contacts but everything was clean and undamaged. Having sought advice from a couple of RR forums on the web, it was suggested that the fault could be the ignition module inside the distributor breaking down or the ballast resistor. I was able to borrow a known, good ignition module and ballast resistor so I could substitute each in turn. With a substitute module I had the same fault so I refitted the original. With a substitute ballast resistor, I also had the same fault so I refitted the original one. I have also fitted a known good coil and I still get the same fault. Today I removed the speed control relay from behind the dash, which is the same type as the fuel pump relay, fitted that in place of the fuel pump relay and I still get the same fault so I refitted the original. I have also checked both fuel pumps independently and they are working perfectly. Because the fault is still the same, despite substituting the parts mentioned one at a time and testing the car each time something was replaced, I think I have proved that the ignition module, ballast resistor, coil, fuel pump relay, switchbox and fuel pumps are all OK. I now have all the original parts back on the car and after 20 minutes running from cold, the relay starts to chatter and shortly afterwards, the engine cuts out so I am back to square one. If anyone has any further suggestions on what to look at next based on what I have found, I would be very grateful. Kind regards, Chris | ||
| Nigel Johnson Frequent User Username: nigel_johnson Post Number: 67 Registered: 12-2008 |
Chris, check the continuity of the feeds to the fuel pump relay when she cuts out. Regards, Nigel. | ||
| Chris Browne Frequent User Username: chrisb Post Number: 80 Registered: 2-2010 |
Hello Nigel, Thanks for that - yes I will do when I am back with the car early next week. If and when I solve the issue, I will report back in case it affects anyone else. Kind regards, Chris | ||
| Jeff Young Frequent User Username: jeyjey Post Number: 68 Registered: 10-2010 |
The petrol pump relay is controlled by the oil pressure sensor. I'd be taking another look at it.... Cheers, Jeff. | ||
| Chris Browne Frequent User Username: chrisb Post Number: 81 Registered: 2-2010 |
Hello everyone, SUCCESS! The culprit was, indeed, the oil pressure switch on the oil filter housing. I pulled the live wire off it this morning and left the engine ticking over for over an hour and it kept running. I took the car out for a 30 mile drive and it never missed a beat. It would seem that the sensor was starting to fail and sending spurious signals to the fuel pump relay behind the speedo which was shutting down the fuel pumps and hence the"fail to proceed". I took a trip down the motorway to see my pals at Spying Flares, bought a new one, came back home and fitted in five minutes and the car is now running perfectly. I can't thank my fellow message board contributors enough as, yet again, they have proved an invaluable source of help and advice. I must admit that I had lost confidence in the car whilst this episode was unfolding but am glad to report that confidence is restored and I look forward to the coming season with renewed enthusiasm. Kindest regards, Chris PS. Apologies to Paul Yorke because if I had read his post and acted on it, I would have solved the problem much earlier. Paul, I promise to pay more attention next time! | ||
| Jeff Young Frequent User Username: jeyjey Post Number: 69 Registered: 10-2010 |
Funny thing is, that very same Paul Yorke just replaced mine a few months ago. ;) Cheers, Jeff. | ||
| Julian Moreno Experienced User Username: morenoj Post Number: 14 Registered: 5-2005 |
Can anyone tell me exactly what of the three oil switch sensors fail, I just replace the upper one that was loosing oil....but continues not working...please can you send me the spare name and number...Thank you very much.. Julian Moreno | ||
| Bill Coburn Moderator Username: bill_coburn Post Number: 1382 Registered: 4-2003 |
Julian/ If you call Flying Spares I am sure they can supply you with one. They are very inexpensive. I buy mine from the local auto supply shop. This is one of those 'things to keep an eye on' bits. If they start to leak change them immediately. And perhaps if that doesn't happen change it every five years anyway! Some years back I was driving a friend's very late Bentley in outback New South Wales and got the miss one pearl one etc treatment from the engine. It finally stopped. And then started again. We limped on starting and conking out until we pulled into a country 'service station. Actuallu, it was two fuel pumps and a tin shed. An old bloke came out to look at the car and I explained the problem. We opened the bonnet and diagnosed none other than the subject switch. More amazing, he had one! A lesson I haven't forgotten! | ||
| Chris Browne Frequent User Username: chrisb Post Number: 82 Registered: 2-2010 |
Hello Julian, Depending how old your Shadow is, there could be two or three sensors on the oil filter housing. The large one, nearest the oil filter is the oil pressure gauge sender. The small one, next to it is the oil pressure warning light sender and if you have a third sensor, this is the oil pressure sender which is connected to the fuel pumps. If the sender senses a drop in oil pressure or, as in my case, is faulty, it sends a signal to the fuel pumps relay which switches off the fuel pumps. If you are having problems with the engine cutting out, as I did, pull off the wire from the third sensor so it cannot switch off the fuel pumps. If it is this sensor which is faulty, a new one is only £20 UK. Simply screw the old one out, put your finger over the hole to stop oil running out, screw the new one in and connect the wire. Hope this helps. Kind regards, Chris | ||
| Julian Moreno Experienced User Username: morenoj Post Number: 15 Registered: 5-2005 |
Thank you very much, my car is SRK36623 1979 and have three sensors, the upper one I change it yesterday with an Jaguar spare exactly the same...it was loosing oil....but nothing good happen I put the wires in the relay and after 6 miles my car stopped again....Sure is the one that goes to the fuel pump relay.....but I need to know exactly the spare number because here we can only get metrical and I have to order it outside, so if you can give me the partt number I will appreciate it very much. Regards from Spain Julian Moreno | ||
| Chris Browne Frequent User Username: chrisb Post Number: 83 Registered: 2-2010 |
Hello Julian, The two smaller sensors are the same part number UE44823. They are available here in the UK for less than £20 UK. Kind regards, Chris | ||
| Julian Moreno Experienced User Username: morenoj Post Number: 16 Registered: 5-2005 |
Thank you very much I will order at soon as possible, King regards, Julian |
