Joe Harrison Posted April 15, 2008 Report Share Posted April 15, 2008 Gidday, I am running a older LEM on a jaguar v12. It was running fine on yesterday, but today when i went to start it, it would just crank and cough and crank and cough. But not start. Sounds so close to starting. I have a seriall link and have had a fiddle with cranking enrichment but nothing seems to make a difference. I've checked that its getting fuel - it is. And it has intermittent spark. Its running a LINK CDI ignitor and standard jaguar coil and distributer. Sometimes it will spark and sometimes it wont. however, it will still not spark when its getting spark. Its really frustrating, as i can't see what could be causing it to fail to start. It was running on the same settings on the link yesterday with no problems at all. And nothing has changed but it just wont start. Could anyone tell me what to look for? and any test i can do to find the cause of the problem. Thanks in advance Quote Link to comment Share on other sites More sharing options...
Simon Posted April 15, 2008 Report Share Posted April 15, 2008 Hi I would leave all the ECU settings as they were when the engine was running as it should. These won't have changed overnight. Im assuming that you have a remote or PC so the first step is going to be to look at all the inputs to the ECU and check that they are reading correctly. TPS, MAP, Engine Temp, Engine RPM (when cranking) this should be stable. Also check earths. If these are iffy all sorts of weird things can happen. Simon Quote Link to comment Share on other sites More sharing options...
Joe Harrison Posted April 15, 2008 Author Report Share Posted April 15, 2008 Hi Simon, The ECU just runs off MAP and RPM. When i have it connected to laptop (this is very hard to do for some reason, it keeps dropping conection, saying link is unavailable, and giving a "exessive aquire error".) but, when i do connect it all the reading make sence. Engine temp 16-24 degrees. It doesnt use the tps and the link says that the tps 1. There are no other "out of it" figures. When i'm cranking, i noticed that the engine rpm fluctuates between 0 and 100rpm. eg. it will be 0 then show 100 for a seccond then go back to 0. Could it be something wrong with my trigger? I kinda ruled that out, as it fires the injectors fine and it is sparking. SO it must be getting a signal. As for grounds, i have check and rechecked and even rewired the grounds. Again, i'm assuming its not these as the ECU and ignition modual appear to be doing their jobs. At the right time though? Cheers Joe Quote Link to comment Share on other sites More sharing options...
Simon Posted April 21, 2008 Report Share Posted April 21, 2008 100 RPM would be a little low and it should be stable. I would be looking at the trigger very closely given what you are seeing with the RPM. Simon Quote Link to comment Share on other sites More sharing options...
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