Shackleton Posted February 28, 2008 Share Posted February 28, 2008 Folks, I still haven't managed to get my Td5 running despite having ruled out immobilisation. The injectors are firing, the glow plugs are heating, the fuel pump is pumping. This is all tested with a simple earth type circuit tester btw. (and my fantastic ears and eyes ) What I've identified is that the likes of the fuel temp sensor and crank position sensor don't seem to be getting a signal sent to them by the ECU. Again tested only with a small circuit tester and at the ECU connector. Anyone know why the ECU wouldn't be sending a signal down these sensor wires (all sensors seem to have a pink and black wire and then various colours on what I presume is the return feed - white and blue in the case of the crank sensor) EDIT: I've located a Brown/Pink wire coming straight from a 20amp fuse and not terminated anywhere. It's also freshly cust so it must have been one of the few I had to cut in the disassembly. The RAVE ciruits say that the EGR modulator, Mass Airflow and Throttle EGR Inlet sensors recieve a feed from a 15amp fuse on a N/K wire. So I'm thinking its this lose wire that carries power (via wherever) to the ECU to power the sensors. Sound logical? So where is it supposed to connect? Quote Link to comment Share on other sites More sharing options...
Shackleton Posted February 28, 2008 Author Share Posted February 28, 2008 Ok after much research I need to ask one simple question: I've read the crank sensor is the induction type. As I understand it, the sensor generates the signal rather then being fed electricity and then sending back signals. Am I right and if so am I wasting my time looking for current coming out of the ECU to the crank position sensor? (any other knowledge on this subject greatly appreciated ) Quote Link to comment Share on other sites More sharing options...
TheRecklessEngineer Posted February 28, 2008 Share Posted February 28, 2008 Don't know the answer to that, but if it does generate the signal then you will need the likes of an oscilloscope to test it. You may be able to with a multimeter with a frequency setting, but may not pick up on it depending on the signal... Have you checked there is fuel getting to the injectors? Are you sure they are firing? If so, then I can't think of any reason why it wouldn't run... Quote Link to comment Share on other sites More sharing options...
Mo Murphy Posted February 28, 2008 Share Posted February 28, 2008 I think that this might be a good time to get Mr. Porny to look at it. Mo Quote Link to comment Share on other sites More sharing options...
Shackleton Posted February 29, 2008 Author Share Posted February 29, 2008 Poor Mr. Porny is tortured with phone calls and txts from me My little ciruit tester flashed quickly when poked into each of the injector wires and the car was cranked. It didn't flash very brightly so maybe the injectors just haven't been getting 12v I've slept on it and came to a few conclusions. In fact I'm becoming quite the expert myself A. It may well be flooded. I'll pull the glow plugs today and see if I can find cylinders full of diesel. B. The crank sensor generates AC so my circuit tester was never going to light anyway. But then I also realised that if the crank sensor wasn't doing what crank sensors do then the injectors wouldn't fire right? C. I'm reading the same story all over the web - people knocking their heads against the wall after testing every little thing but the car still won't start. And it usually comes back to the battery not being 100% D. I have a few wires (just instrumentation stuff) mixed up - I know cause when I turn the Ign on the temp guage goes through the roof. I'm thinking these could be compounding an already dubious charge from the battery. So happens I was given a present of a boost box last night, plus I've been giving the battery a little TLC over night too. I'll pull the plugs, drain any diesel, cut and insulate all non essential wiring, throw in a few extra earths for good measure and try the battery with a hand from the booster. Failing all that I'll get another battery. Quote Link to comment Share on other sites More sharing options...
Porny Posted February 29, 2008 Share Posted February 29, 2008 Poor Mr. Porny is tortured with phone calls and txts from me My little ciruit tester flashed quickly when poked into each of the injector wires and the car was cranked. It didn't flash very brightly so maybe the injectors just haven't been getting 12v I've slept on it and came to a few conclusions. In fact I'm becoming quite the expert myself A. It may well be flooded. I'll pull the glow plugs today and see if I can find cylinders full of diesel. B. The crank sensor generates AC so my circuit tester was never going to light anyway. But then I also realised that if the crank sensor wasn't doing what crank sensors do then the injectors wouldn't fire right? C. I'm reading the same story all over the web - people knocking their heads against the wall after testing every little thing but the car still won't start. And it usually comes back to the battery not being 100% D. I have a few wires (just instrumentation stuff) mixed up - I know cause when I turn the Ign on the temp guage goes through the roof. I'm thinking these could be compounding an already dubious charge from the battery. So happens I was given a present of a boost box last night, plus I've been giving the battery a little TLC over night too. I'll pull the plugs, drain any diesel, cut and insulate all non essential wiring, throw in a few extra earths for good measure and try the battery with a hand from the booster. Failing all that I'll get another battery. You could try getting it to start with a can of Eazi-start!! Make sure the thick brown wire inside the engine loom has a good 12volts - needs to be a 30amp supply. As mentioned you need a oscilloscope to check crank sensor feed.. but you can check continuity back to the ECU. The crank sensor should be connected to pins 36 and 13 of the red plug going to the ECU. Then I fit some extra good earths, ideally straight from the battery to the engine block. Fuel temp sensor you can ignore until the engine is running. On the black Plug going to the ECU check that pins 1, 2, 24 and 25 go to a good earth point. The Cut wire is a bit more interesting.... looking at the wiring diagram... There should be a brown/pink wire should be from pin 22 of the red ECU plug, then it changes to Brown/Black and is connected to injectors 1, 3 and 4... and is the power feed for these injectors.... there should also be a brown and orange wire that feed injectors 2 and 5 this comes from pin 23 of the red plug. Although I only have the post 2002 wiring diagram here. And p.s. ignore the boost box, until you've got a remap that is matched to it.... otherwise you will underfuel at the top end and loose power - have a read of the lowered 90 - update thread lol. Ian Quote Link to comment Share on other sites More sharing options...
Shackleton Posted February 29, 2008 Author Share Posted February 29, 2008 Nah I meant like a jumper booster, crocodile clip battery helper, jump start thingy whatsit Standby for new thread... Quote Link to comment Share on other sites More sharing options...
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