Expat Posted August 11, 2015 Author Share Posted August 11, 2015 No new email since Lotus7 club advised me of yours of 18h35. Not in the junk file either. Link to comment Share on other sites More sharing options...
CA Sevener Posted August 12, 2015 Share Posted August 12, 2015 JK: thanks for the idea, putting a monitoring connection on the fuel pump will be my next approach.Simon_h: I appreciate the Evora lead. Some quick searching did indeed turn up the right kind of photos...I will do some more digging. Do you happen to know any of the following that has been intriguing me:1) Is the Lambda sensor wideband or not?2) Is the ECU locked or is there some way to link in to this ECU over and above an OBDII monitor?3) How does the immobilizer work?The fuel pump seems to use the earth at the rear of the car. It is at the back of the transmission tunnel. While the bolt is tight etc., your comments are going to encourage me to actually take it apart, clean and reassemble.What is really getting at me is that this problem was not present for the first 2k miles and when the car is running, there is not hint of it. Ah well, the joy of 7 ownership. Link to comment Share on other sites More sharing options...
simon_h Posted August 12, 2015 Share Posted August 12, 2015 Mark,The lambda is not wide band, its just a normal switching sensor.The ECU is locked down and the only data available is that the is down the OBD port. Its not going to be quick enough for logging but does work with most scan tools. I saw, on your blog I think, you asked about some OBD stuff, cat mon and o2 readiness? Anyway they are not enabled as its not required for the level of approval the 7 is at in Europe. There is no rear o2 so cat mon is not possible for example.As far as the immobiliser goes, intermitantly I would say!I think there should be enough info on the diagrams you have to work out the ECU pin out if you cant find one. As I say it wont be exactly the same as a Lotus but close.As to why it didnt do this and does now I really dont know. Wiring would still be my first guess. Link to comment Share on other sites More sharing options...
CA Sevener Posted August 21, 2015 Share Posted August 21, 2015 Expat and others,Had a day off work today, so I put the car on axle stands and slid underneath. I undid, sanded and retightened the rear earth point and the earth points at the front of the loom near the ECU (these are attached to a bolt that holds the ECU to the top of the aluminum bulkhead beneath the battery.After all this...no change. One thing I did notice after some extensive start/stop testing was that when the car did not start the oil pressure and water temp gauges behaved oddly and instead of their usual move to their correct positions, when the engine was cranked, they swung hard over to maximum. Does this point to anything?It leads me to believe that perhaps the front ECU loom earth points could be better placed. Does anyone have some ideas here as to what might be better?Here's a picture of the earth tags bolted to the ECU tab, between the battery & heater here.Mark Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted August 22, 2015 Member Share Posted August 22, 2015 ... the oil pressure and water temp gauges behaved oddly and instead of their usual move to their correct positions, when the engine was cranked, they swung hard over to maximum. Does this point to anything? There was an explanation of this but I can't remember it. (And I always forget which way the resistance changes and have to look it up.) If it's consistent could you add the instantaneous battery voltage when this happens.Jonathan Link to comment Share on other sites More sharing options...
CA Sevener Posted August 22, 2015 Share Posted August 22, 2015 JK, I wish I could, but it happens intermittently and mostly when I am actually out and about. I am going to think about the best way to be able to monitor the voltage on the battery and on the fuel pump. The temp and oil pressure are not directly connected to the sensors on the EU5, but I believe are controlled by the ECU.The process to get it to start is simply to switch off the ignition, wait for the immobilizer to kick back in (~30 secs) and then try the starting process again. So far it always has started, with a worst case of perhaps 5 of these switch off and wait cycles. The engine always cranks solidly, so I was not suspecting a battery issue.you can always tell if it is going to start before it does because you either hear the fuel pump or not.i moved the ECU connections directly to the battery yesterday afternoon, but have not had time to test it, except to verify the car would start, and of course it did first time then...but I have learned that that this is not an indication of a real fix, yet.Mark Link to comment Share on other sites More sharing options...
Expat Posted August 25, 2015 Author Share Posted August 25, 2015 CA Sevener:Interesting photo. Here's mine for comparison. As you can see the bolt holding the ECU in place is not used as an earth; one holding the battery carrier is used instead. And I can only find one earth!I have now done nine starts in succession with no problems and, above all, no refusals to start. Maybe we've cracked it ; I doubt it ,but will keep cleaning earth points as and when I find them! /sites/default/files/images/users/6502/DSCN0034-01.jpg Link to comment Share on other sites More sharing options...
CA Sevener Posted August 26, 2015 Share Posted August 26, 2015 Expat,interesting. Do you have the main battery negative attached to the engine? I am assuming that this connection is the earth for some of the loom points to ground?good news on the starting. I have not resolved my version of the problem. By the way, do you always get to hear the fuel pump priming on the final ignition position before cranking the engine?Mark Link to comment Share on other sites More sharing options...
Nigel Riches Posted August 26, 2015 Share Posted August 26, 2015 Hi Ex pat, have you tried shorting the wires of the start button together, or substitute another grunty switch in its place, the problem you describe sounds like an intermittent connection in the supply voltage to the ecu, might be something else for you to rule out. Nigel Link to comment Share on other sites More sharing options...
Expat Posted August 26, 2015 Author Share Posted August 26, 2015 CA Sevener:There are two thick (8 or 10mm) leads coming from the battery negative terminal one goes to the chassis and can be seen in bottom right of my photo. the other goes to the engine using one of the bell housing bolts.One of the things I have tried to train myself to do is listen out for the fuel pump, but I often forget! Sorry, but I can't give a definite answer to your question yet. I'll keep on training cos I like the sound of your starting technique! If nothing else it should hammer the battery a little less.Nigel: Everything lights up on the dash on the first push of the START button so I don't think it's the button.It could well be an intermittent supply (or earth) for the ECU. Not having a pinout makes it difficult to know where to look. I have cleaned one ECU earth connection as mentioned above (post 43) and, so far, have had no trouble. Having said that I can almost guarantee that it won't start tomorrow! Link to comment Share on other sites More sharing options...
CA Sevener Posted August 27, 2015 Share Posted August 27, 2015 Expat, thanks for the battery lead description. That sounds like a much neater plan to the one I have. I have a spare thicker lead too. Another thing to try.Nigel: I also had thought that it was something to do with power to the ECU. I thought it was the ignition switch being intermittent, so put a new one on thanks to Derek at Caterham. However, no change. Perhaps this second ignition switch is also intermittent? It's possible... I may try some hard wiring.Mark Link to comment Share on other sites More sharing options...
Expat Posted August 28, 2015 Author Share Posted August 28, 2015 Just talked to the people who sold me the R300 (Caterham Competition France), who are now back from holiday, and the head mechanic (Benoit) says that he knows this problem and the cure is most likely (99%) to bypass the immobiliser. He knows how to do this and can even give instructions over the phone to a competent (French speaking) mechanic.Hope this helps Link to comment Share on other sites More sharing options...
Expat Posted September 23, 2015 Author Share Posted September 23, 2015 Found out how to remove immobilizer, so I did! And replaced it with a dummy which hard wires the feeds to the ECU and/or fuel pump and starter motor (Which never gave any trouble anyway).Just to note also that there has been no trouble starting since I cleaned up a few earths. Only time will tell if I've cracked it or not! Link to comment Share on other sites More sharing options...
Tony Whitley Posted September 26, 2015 Share Posted September 26, 2015 Fingers crossed! Link to comment Share on other sites More sharing options...
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