revilla Posted September 9, 2016 Share Posted September 9, 2016 I know I'm a long way away but if you wanted to come up one weekend I'd me more than happy to work through the loom with you to track down exactly where the voltage drops are occurring. It's very hard to do over the internet, a lot easier with a car in front of you. Link to comment Share on other sites More sharing options...
Paul Deslandes Posted September 9, 2016 Share Posted September 9, 2016 1. It's important when measuring voltage that both meter probes are placed at the positive and ground terminals of the item at which it's being measured, e.g. the ECU. If you put the negative meter probe somewhere randomly on the chassis, engine block or battery, you're likely not going to see voltage drops due to poor earths, which is a possible/probable candidate for the problem. This would cause the chassis terminal voltage to rise above the car chassis voltage, rather than the positive supply voltage dropping, but the effect on the ECU would be the same - i.e. low supply voltage.2. The positive voltage supply to the injectors is not via the ECU but comes straight from the +12V supply, either direct from the battery, via an ignition switched relay or the ignition switch - hopefully not the last. The injector actuating signal from the ECU is simply switched between OFF, i.e. open circuit, or ON - switched to ground. As noted before, all the injectors are connected in parallel and fire at the same time, so only the signal wire is connected to the ECU plug.3. Going back through the plethora of posts to this thread, it seems that the starter is happily cranking the engine without too much voltage drop at its terminals, however the ECU is reporting that it's supply voltage (reported as battery voltage) is only 6 or so volts when cranking. I'm really struggling to reconcile those symptoms with the engine starting and then continuing to run once it's had a squirt of fuel, unless the voltage at the ECU drops during cranking sufficiently to stop firing the injectors and rises enough to do so once cranking has stopped. If that's the case then why the heck does it then start normally thereafter?Flummoxed I am.Paul Link to comment Share on other sites More sharing options...
John Vine Posted September 10, 2016 Share Posted September 10, 2016 If that's the case then why the heck does it then start normally thereafter?A very pertinent question, which has been bothering me since the very beginning. Could it be because the engine has warmed up (a little, at least)? If so, the finger points once again at inadequate cold-start enrichment. Back in post #47, you said: I'm assuming the ECU is locked so you can't get at the TPS voltage/load site curve to see at what voltage the site 0 to site 1 transition occurs. Pity if so.A while ago, I offered Piers a PIN that might allow access (it did on my old 1.8K SS-R). If it does work, how would he go about checking what you suggest? And would he be able to establish if/when any enrichment should occur, and then to amend it if found wanting? Also, could he try removing one of the injectors to observe whether or not it actually squirts out fuel while cranking from cold? (I've never tried this -- is it even possible?) I imagine that would confirm two things: (1) whether or not the firing voltage during cranking is adequate, and (2) whether or not the fuel rail pressure is adequate. Flummoxed I amAs are all of us! And if you are, I fear the problem moves ever further away from a solution!JV Link to comment Share on other sites More sharing options...
Paul Deslandes Posted September 10, 2016 Share Posted September 10, 2016 JVI think Piers must have been able to 'open' the ECU with the PIN you gave him as he's been able to view the Easimap pages. Provided the relevant data boxes have been opened, you can read the TPS voltage and the load site, either as a digital number or on one of two analogue 'dials', the other being engine revs. The load site should be zero at idle and progress up to 15 as the throttle is pushed to fully open. You can see this happening with the ignition on even if the engine isn't running.I'm not that familiar with roller barrel throttle bodies but I'm sure they're similar to standard bodies with a single fuel rail supplying all four injectors. You could only pull out all four injectors, still attached to the fuel rail, but I wouldn't suggest switching on the fuel pump with them out of the engine as a) you'd be potentially spraying fuel everywhere and b) the pressure could easily blow the injector out of the rail coupling, even though they should be clipped in. The best thing would be to monitor the injector voltage and signal with an oscilloscope, however in the absence of one of those, monitor the supply side and signal connections with an analogue voltmeter. This is on the basis that, if the voltages look right then the injectors must be opening correctly and, assuming sufficient fuel pressure, fuel is being delivered to the engine.If Piers would like to download the ECU .ecc file and email it to me, it might be possible to see how/whether the cranking fuel can be enriched. But I still believe we need to get the bottom of the voltage drop issues first as nothing will work properly if there is a voltage problem.What will we do to pass the time when Piers' car is sorted?Paul Link to comment Share on other sites More sharing options...
John Vine Posted September 10, 2016 Share Posted September 10, 2016 Thanks for that, Paul. Re R300 RBs, the injectors all hang off a single fuel rail, as you surmise -- in fact, the rail is the same as on the standard 1.8K although I believe the injectors are uprated. I suppose it's also possible to check whether the injectors are opening by using the old "long screwdriver in the ear" trick, always assuming you could hear them over the noise of the starter! JV Link to comment Share on other sites More sharing options...
Area Representative Piers300 Posted September 10, 2016 Author Area Representative Share Posted September 10, 2016 Hello AllAgain thank you for your patience and remember you are dealing with a not very savvy PC guy.Yesterday, I looked to see how you put the password/number into the system and made no progress. I also looked to see how I save the existing ECU file. I am going to have another go tomorrow as I have a house full today.Thanks Piers Link to comment Share on other sites More sharing options...
Area Representative Piers300 Posted October 8, 2016 Author Area Representative Share Posted October 8, 2016 An update. On Friday, I had an appointment at Sevens & Classics at Brands Hatch. I got there early so the car could cool down. Kevin, their technician pretty quickly found the problem. Under the throttle bodies is a multi pin connector and I had been unable to get it separated. Kevin got it apart and found the connections were green with corrosion. He used switch cleaner and left it to soak and then refitted the connector twice to ensure a good contact . The car had not run for at least two and a half hours started first turn of the keyHe the balanced the throttle bodies, reset the TPS and adjusted the idle and it now ticks over very smoothly. This morning I went out to the garage and on the third attempt, it started. So it's looks like S&C have cracked the problem and the charge for their time was very reasonable. A big thank you to Andy, Tim and particularly Kevin at S&C for sorting this problem. Piers Link to comment Share on other sites More sharing options...
SM25T Posted October 9, 2016 Share Posted October 9, 2016 Great news. 182 posts for a successful fix ! Corrosion in engine bay connectors is often a problem with a car like the 7. I occasionally disconnect mine and put a spot or two of water displacing oil in the sockets. Now you have a warm summer of missed drives to catch up on !! Link to comment Share on other sites More sharing options...
Area Representative Piers300 Posted October 9, 2016 Author Area Representative Share Posted October 9, 2016 It started first turn of the key this morning. So well done S&C who have cracked the problem.It has been washed ready for a suitable run out or the next secret KENT Blat. I missed one this morning as I had family staying.Piers Link to comment Share on other sites More sharing options...
John Vine Posted October 9, 2016 Share Posted October 9, 2016 Excellent news, Piers! And well done, S &C.The comment in post #99 has indeed proved prescient!JV Link to comment Share on other sites More sharing options...
Area Representative Piers300 Posted October 10, 2016 Author Area Representative Share Posted October 10, 2016 John - I tried to separate the multi pin connector on a number of occasions and basically gave up. It took Kevin from S & C a little time to get it open. I also think my friends from the Club, Paul and Mike also had a go with no success.I am having a run out tomorrow to Headcorn Aerodrome, so we will see how it goes. Piers Link to comment Share on other sites More sharing options...
7 wonders of the world Posted October 10, 2016 Share Posted October 10, 2016 and on the third attempt it started..........It should be starting first time every time ! Link to comment Share on other sites More sharing options...
L7 FST Posted October 10, 2016 Share Posted October 10, 2016 Good news - & fingers crossed for the morning! Link to comment Share on other sites More sharing options...
Bottrill Posted October 10, 2016 Share Posted October 10, 2016 Congrats Piers. I believe It's the plug Ben, a previous owner of mine, had issues with as mentioned. Now get out and enjoy it!Lee Link to comment Share on other sites More sharing options...
Paul Deslandes Posted October 10, 2016 Share Posted October 10, 2016 Do we know what this plug connects to and what it does and how it's controlled? I for one would really like to know as it's had me going for ages as to what the problem was. Absolutely delighted that you've got it sorted Piers, you have a lot more patience than I do.Paul Link to comment Share on other sites More sharing options...
Area Representative Piers300 Posted October 11, 2016 Author Area Representative Share Posted October 11, 2016 Paul. I should have asked what the multi pin connector carries. I do not know what it carries. I assume it is signal cables.Piers Link to comment Share on other sites More sharing options...
Paul Deslandes Posted October 12, 2016 Share Posted October 12, 2016 If anyone knows it would be useful information when helping with fault diagnosis.Hope you can enjoy the car now.Paul Link to comment Share on other sites More sharing options...
Area Representative Piers300 Posted February 19, 2017 Author Area Representative Share Posted February 19, 2017 Oh Dear - here we go again.Yesterday as the sun was out, I decided to start the 7 for the first time since going to the London to Brighton meeting in November. The car was put away after the LTB, till yesteday and it started third press of the starter button. A quick run round the block and put away till today when I was going to give a good clean.So today, it just cranks as it used to and has not fired once. I suspect the multipin connector under the throttle bodies and I have tried to seperate it without success. I don't want to damage the connector, so can someone advise how to seperate it, so I can spray some contact cleaner onto the connectors. The car is still dry and not been washed yet, so no water ingress.Thanks in advance. Piers Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted February 19, 2017 Member Share Posted February 19, 2017 What's the battery voltage while cranking?Can you hear the fuel pump?Can you add a photo of the connector you want to open?Jonathan Link to comment Share on other sites More sharing options...
Area Representative Piers300 Posted February 19, 2017 Author Area Representative Share Posted February 19, 2017 JonathanIt started on Saturday on the thrid press of the starter button after not being started since November. I am 100% convinced it is a bad connection. It had a new battery and also a new starter motor in September and it is cranking very well.I think it was 10.7 VDC when cranking on the old battery before I replaced it and cleaned up the earth points and other main connections.Yes fuel pump is running.I have not yet squirted fuel into the T/B's, but I am 100% sure it will start if I do.I will get out tomorrow and try and get the connector appart. This was pin pointed by Sevens and Classics as the problem when they found the connector was full of corrosion.Sorry, I don't have a photo of the connector. It is browny/white and approx 16 way. It looks to have two clips, but I need to know how to seperate it. Somehow, you havev to lever both to get it appart.Piers Link to comment Share on other sites More sharing options...
Area Representative Piers300 Posted February 20, 2017 Author Area Representative Share Posted February 20, 2017 Connector now seperated and spayed with contact cleaner - sprayed twice and no difference. It will still not start from cold. So squirted fuel into the throttle bodies and it starts first press of the button.The connector has two seperate levers that both have to be fully pressed in and the connector then comes apart. Simple when you know how.Piers Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted February 20, 2017 Member Share Posted February 20, 2017 ... fuel pump is running.Connector now seperated and spayed with contact cleaner - sprayed twice and no difference. It will still not start from cold. So squirted fuel into the throttle bodies and it starts first press of the button.That helps narrow it down. I'd still want to know the ECU wasn't dropping out.What's the modern equivalent of pulling the fuel line off and seeing if fuel is pumped out?JonathanPS: The connector has two seperate levers that both have to be fully pressed in and the connector then comes apart. Simple when you know how.... and have the confidence to use a bit more force on the release levers! :-) Link to comment Share on other sites More sharing options...
John Vine Posted February 20, 2017 Share Posted February 20, 2017 Very sorry to hear your problems have returned.When you say:"So squirted fuel into the throttle bodies and it starts first press of the button."Were you actually cranking the engine when you squirted fuel in, or did you squirt in the fuel and then press the red button?If the former, did the engine fire while it was still cranking, or only after you stopped cranking (but with the engine still spinning)?I'm trying to reconcile the combination of cranking voltage, sparks and injectors.JV Link to comment Share on other sites More sharing options...
Area Representative Piers300 Posted February 20, 2017 Author Area Representative Share Posted February 20, 2017 John - Thanks for your message above.To answer your questions:1) I was on my own, so I squirted as small amount of fuel into all throttle bodies with the throttle slides held open, by the central throttle arrangement. I then turned on the ignition and pressed the starter button and it started immediately.2) The engine fired immediately on cranking. Piers Link to comment Share on other sites More sharing options...
Area Representative Piers300 Posted February 20, 2017 Author Area Representative Share Posted February 20, 2017 JohnI should have added that when I first started the engine by squirting in fuel this afternoon, I let it run for 10 minutes or so, to get the engine up to temperature.Once the engine was hot, I stopped the engine and turned off the ignition. I then turned the ignition back on and pressed the starter button and it did start immediately.Piers Link to comment Share on other sites More sharing options...
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