John Vine Posted July 16, 2016 Share Posted July 16, 2016 Hi Piers,Thanks for the feedback.I believe my SS-R had a diagnostic plug in the engine bay (rather than under the dash). I'll check and report back.Re a comms cable for your 967, I see one has recently been added to the Equipment for Loan Register (item #53).JV Link to comment Share on other sites More sharing options...
John Vine Posted July 19, 2016 Share Posted July 19, 2016 Hi Piers,My S-in-L has just sent the following photos of the diagnostic cable hooked into his 967 ECU.The first shows the location of the cable:The second confirms that this is an RS232 serial cable:Hope this helps,ETA: Just to clarify that this cable wasn't fitted by CC but by a Lotus Service Centre in an attempt to resolve a persistent misfire.JV Link to comment Share on other sites More sharing options...
Area Representative Piers300 Posted July 19, 2016 Author Area Representative Share Posted July 19, 2016 Hi JohnThe cable is being installed on Saturday, so watch this space. Piers Link to comment Share on other sites More sharing options...
Paul Deslandes Posted July 19, 2016 Share Posted July 19, 2016 RS232 yes, but not standard pin outs at the ECU end of the cable. If making your own cable, follow the SBD diagram but don't worry too much about the resistors which can be left out or both either 1k or 1.2k Ohms.Paul Link to comment Share on other sites More sharing options...
Area Representative Piers300 Posted July 24, 2016 Author Area Representative Share Posted July 24, 2016 Well, I think we have a result. Arnie Webb very kindly came over to my house on Saturday. He said the first thing that needed doing was to install the RS232 cable into the ECU, as without it, we were in the dark to what was going on. He already suspected one item and this would show up on the laptop once connected. So once the cable was installed and connected to his laptop, we cranked the engine and Arnie noticed that the signal from the flywheel sensor was very strange and all over the place.We removed the flywheel sensor, something I have not replaced and found a bit of swarf on the magnetic tip. This was what Arnie suspected from the start. As the sensor looked rather tatty, a quick trip into Canterbury where we got a new unit. When installed, the car started first press of the button and has continued to do so since yesterday. The signal from the new sensor was as it should be on the laptop.So it looks to have been the crankshaft sensor that was causing the problems and some regular starts from cold should prove we have cracked the problem.A very big thank you to Arnie Webb for his time to sort my problems out. Piers Link to comment Share on other sites More sharing options...
John Vine Posted July 24, 2016 Share Posted July 24, 2016 Well done, chaps! ETA: But I'm still puzzled why the engine should start with a shot in the RBs, and then idle well once started....JV Link to comment Share on other sites More sharing options...
Area Representative Piers300 Posted July 24, 2016 Author Area Representative Share Posted July 24, 2016 I am told by Arnie, that the ECU gets it signal from the crank sensor and then the ECU gives the engine some fuel. As the signal from the crank sensor was rubbish due to the swarf on the tip, the ECU was not giving the RB's any fuel, hence it would start if you squirted some in and the speed increased which was sufficient for the system to run and get a better voltage from the sensor. Piers Link to comment Share on other sites More sharing options...
John Vine Posted July 24, 2016 Share Posted July 24, 2016 That makes sense, Piers. Thanks. JV Link to comment Share on other sites More sharing options...
EEK Posted July 24, 2016 Share Posted July 24, 2016 Hindsight is of course 20/20http://www.ecutesting.com/rover_non_starting_common_faul.html Link to comment Share on other sites More sharing options...
Bottrill Posted July 24, 2016 Share Posted July 24, 2016 Piers, I'm genuinely happy to hear the good news. Please let me know how the car behaves over the next few startups. Unfortunately I may have spoken too soon. The lasts two attempts have resulted in our original symptoms on my R300. The car is booked in with Nick Potter for its annual service plus fuel filter change in a few weeks so I will ask him to take a look at the crank sensor based on your findings. Lee Link to comment Share on other sites More sharing options...
revilla Posted July 24, 2016 Share Posted July 24, 2016 But if the ECU wasn't getting a decent crank sensor signal, how could it be firing the ignition (and at the right timing)? Not saying that wasn't the cause, would just like to understand in detail. Link to comment Share on other sites More sharing options...
John Vine Posted July 24, 2016 Share Posted July 24, 2016 But if the ECU wasn't getting a decent crank sensor signal, how could it be firing the ignition (and at the right timing)?That's a very good question. I look forward to the definitive explanation!Piers: Ks (certainly the EU2s) are known to suffer from interference affecting the crank sensor. Angus (and Tessa) reported this problem here (about halfway down, under "Actual problem..."). It might be a good idea to check that your crank sensor lead is well away from HT leads.JV Link to comment Share on other sites More sharing options...
Area Representative Piers300 Posted July 24, 2016 Author Area Representative Share Posted July 24, 2016 Lee The replacement sensor from Eurospares was £23 and is pretty easy to replace. It just bolts into place and has a plug and socket arrangement .I will get you the part number tomorrow as sitting in bed reading posts at the moment. Revilla when Arnie connected to the ECU and we cranked for the first time, the software displayed some very strange readings from the sensor, no doubt caused by the swarf on the tip of the sensor. As I understand it, the ECU would not switch on the fuel with this incorrect signal. I am no expert in this at all so it is from my memory from talking to Arnie. By squirting fuel into the t/b's , the engine starts and I must assume that the voltage from the sensor gets better and the ECU then gives fuel. John the wiring for the flywheel sensor is a fair distance from the new HT leads, as it is down by the clutch cable. However the HT lead from the coil runs quite close. I will check it tomorrow when I do some start tests Piers Link to comment Share on other sites More sharing options...
Area Representative Piers300 Posted July 25, 2016 Author Area Representative Share Posted July 25, 2016 Lee. The crankshaft sensor is Euro Car Parts no: 419750061 and had a list price of £72.26 and I paid £23.49. Description is crankshaft sensor Rover/MG 2. I am not quite sure why the discount but probably a cash sale. Piers Link to comment Share on other sites More sharing options...
Bottrill Posted July 25, 2016 Share Posted July 25, 2016 Many thanks Piers. I will take a look tomorrow. All makes sense reading the above. I will let you know how I get on.Lee Link to comment Share on other sites More sharing options...
Area Representative Piers300 Posted July 25, 2016 Author Area Representative Share Posted July 25, 2016 Unfortunately, the car would not start today, but did fire once or twice on the first attempt. Since then and numerous attempts - nothing, so we are not there yet. Incredibly frustrating and I have not squirted fuel into the t/b's and I am sure it will then start. Only thing that has not been replaced is the TPS, but when connected to the laptop, it seemed to be working to specification. I did take out the new crankshaft sensor and put the old one back in, but no difference so the new one went back in.Piers Link to comment Share on other sites More sharing options...
revilla Posted July 25, 2016 Share Posted July 25, 2016 Can you connect a voltmeter between one of the terminals on the intertia switch (either one if you can do it without disconnecting) and earth and see what it shows when cranking? It should read zero when the engine is stopped, something like battery voltage when it's running ... But I'd be interested to know what when it is cranking but refusing to start. Basically, is the ECU powering the fuel pump when cranking or not. Link to comment Share on other sites More sharing options...
Bottrill Posted July 25, 2016 Share Posted July 25, 2016 We seem to be going round in circles don't we Piers. I removed my crank sensor this aft and indeed it did look like it had seen better days as the tip was typically grubby, but as it is a magnetised I was wondering whether this would effect its use. I have picked up a replacement (thanks for the part number) so will fit this tomorrow morning. Once warm, mine will start on the button. After a few hours and a cold engine the issue resurfaces. Same with yours?Lee Link to comment Share on other sites More sharing options...
Area Representative Piers300 Posted July 25, 2016 Author Area Representative Share Posted July 25, 2016 Lee. Yes, it seems that we have the same issue. If I start it by squinting fuel in the T/B's, away it goes and it runs smoothly and goes well. Last week, I went to the local 7 Club Meeting. I had to squirt fuel in to start the car at home and I had a 40 minute run to the meeting. So after eating, we came out and it started first time, so I felt confident it would start when time to leave. Another 45 minutes of chat and time to go and of course it would not start, much to everyone's amazement. A quick squirt and away it went and ran fine.The only thing I have not replaced is the ECU and the TPS and then there is the wiring.. Plus I do have he original in tank pump, but this was checked when serviced and was I think 3.5 bar at the fuel rail.Lee. I will keep you in the loop on all developments. Piers Link to comment Share on other sites More sharing options...
Area Representative Piers300 Posted July 25, 2016 Author Area Representative Share Posted July 25, 2016 Hi Lee. I believe that all speed sensors have a magnetic tip. The ones I use at work on large Diesel engines will pick up swarf particles, caused by the starter motor ring gear engagement. When it happens, the ac voltage coming out of the magnetic pick-up is very badly effected and the speed control system goes a bit haywire. Piers Link to comment Share on other sites More sharing options...
Bottrill Posted July 26, 2016 Share Posted July 26, 2016 Hi Piers, have you tried priming the fuel rail/lines a couple of times with the ignition on/off before engaging the starter? I think a gentleman earlier in the thread mentioned it? It is bizarre how changing the crank sensor immediately solved the issue for you (I'm assuming when cold?) then reverted back to the original problem. That possibly indicates a signal to ECU wiring issue somewhere?Has the issue always been like this with your car or has it got progressively worse recently?Lee. Link to comment Share on other sites More sharing options...
Area Representative Piers300 Posted July 26, 2016 Author Area Representative Share Posted July 26, 2016 Hi Lee. No I have not tried the on off priming. I will try it later today. Going back six years when I got he car, it was never that easy to start, but it always did start. We have done two IOW trips and on both occasions it would not start, but eventually did after a lot of fiddling, as I always thought it was an ignition problem. In the last four months since coming back from the IOW, it has got really bad to the extent it does not even fire when cranked.Like you, I think it is probably something simple like a bad connection, because if I squirt in fuel, it starts and runs fine and keeps running and will restart when hot - sometimes. Piers Link to comment Share on other sites More sharing options...
John Vine Posted July 31, 2016 Share Posted July 31, 2016 All incredibly frustrating, Piers. Just to recap...If the engine won't fire, but does start with a fuel shot into the RBs, somewhere along the way the ECU is either not telling the fuel pump to run, or not telling the injectors to fire, or not telling them to fire for sufficient time. The fact that it starts when fuel is available suggests the ignition is working OK.Have you had a look at the map and whether the TPS is set correctly at idle? A few more thoughts....What gaps do your RBs have when closed?What spark plugs are fitted?Do CC have any suggestions?JV Link to comment Share on other sites More sharing options...
Bottrill Posted July 31, 2016 Share Posted July 31, 2016 Piers,just to add to Johns post above, trawling through the archives I stumbled upon a thread from Ben Ferrey, a previous owner of my car. He had issues with the car not starting at one point which was diagnosed to the large grey connector under the throttle bodies. There was a loose wire in one of the terminals. Worth a look....Lee Link to comment Share on other sites More sharing options...
Area Representative Piers300 Posted July 31, 2016 Author Area Representative Share Posted July 31, 2016 Lee. Thanks for the tip on the connector. I will have a look after the German GP.i did look at it before but could not get it undone. How does it release? Piers Link to comment Share on other sites More sharing options...
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