Paul Deslandes Posted July 12, 2016 Share Posted July 12, 2016 Piersthat sounds as though they knew what they were doing. The other component that can cause problems with fuel pressure is the regulator although they rarely give much trouble. I only threw in the comment about the air filter because I recalled the awful, and expensive, problem it caused, rather than suspecting is was contributing to your problem.That MBE ECU is likely to be a 967 type, in which case it's almost certainly locked with a PIN rather than encrypted. If you have the PIN you can look at the maps and even tweak if you wish. There is a standard PIN that is often used but unfortunately I don't have a record of it although I'm sure someone on here will be able to advise if you wanted it. Otherwise it is possible to decode the PIN from the ECU itself using some cunning software. There are also issues about which version of Windows you run Easimap under. There was an extensive thread earlier this year on the subject.Keiththe meter is reading 4.3k not 4.3 Ohms. The clue is that the meter scale is shown as 20k, meaning that the units are thousands of Ohms. Trying to adjust to 4.3 Ohms would be almost as daft as 0.43 as the track resistance of the TPS is approximately 5k, so still only 0.1% of the range.Minister or CC ought to be asked to edit and reissue the setup instructions.Paul Link to comment Share on other sites More sharing options...
John Vine Posted July 12, 2016 Share Posted July 12, 2016 Well, the CC guidance specifies 0.43-0.45v across pins 2+3 with the RBs closed, so that seems clear enough.OTOH, the Minister guidance quoted above appears to be wrong in two ways: magnitude and units. it should surely read 4.50 KOhms and not 0.45 Ohms. However, if as I understand it Minister is no longer in business, I guess there's little mileage in requesting a correction.Re my 20K reading being 4.30 KOhms and not 4.30 Ohms, this is of course the inevitable result of having to handle resistances between 1 Ohm and 2 Megohm on a device with a limited 4-digit display. The only way to achieve this (on the cheaper meters, at least) is to have several ranges. Re using resistance rather than voltage to set the TPS, I can now see why Minister specified the former. Using voltage requires the TPS to be hooked up to a 5v reference source (normally the ECU itself), whereas an engine builder like Minister might well prefer to use resistance instead, obviating the need for the reference voltage.JV Link to comment Share on other sites More sharing options...
Paul Deslandes Posted July 12, 2016 Share Posted July 12, 2016 very interesting thought JV, I reckon you're spot on there. Get a preliminary, get it started setting and tweak once it's installed. Link to comment Share on other sites More sharing options...
Bottrill Posted July 12, 2016 Share Posted July 12, 2016 Excellent news Piers. A nice feeling I assume?!those C-Tec charges are great. I purchased the 5.0 and the 12v cigarette adapter when I bought the car.Have you replaced both the inline and tank filters? Lee Link to comment Share on other sites More sharing options...
Area Representative Piers300 Posted July 12, 2016 Author Area Representative Share Posted July 12, 2016 Lee - I just did the in-line filter that is located behind the drivers seat. I did not know there was another one, Where is it ?Piers Link to comment Share on other sites More sharing options...
ECR Posted July 12, 2016 Share Posted July 12, 2016 It's a mesh sock on the inlet to the fuel pump inside the fuel tank. You'll need to remove the pump if you need to clean that .... Link to comment Share on other sites More sharing options...
John Vine Posted July 12, 2016 Share Posted July 12, 2016 To help those struggling to understand multimeter resistance ranges, and how to interpret the display, I've knocked up a little chart here.Please let me know if it's unclear or if I've made any errors.JV Link to comment Share on other sites More sharing options...
Bottrill Posted July 12, 2016 Share Posted July 12, 2016 Is this a serviceable item or more a case of catching larger debris entering the pump and letting the inline fuel filter do most of the work? Lee Link to comment Share on other sites More sharing options...
ECR Posted July 12, 2016 Share Posted July 12, 2016 Yes, its a plastic mesh pre filter to stop the bigger bits damaging the pump or clogging the inline filter. It can be prised off the pump and cleaned. If big bits are evident, I'd clean out the tank at the same time. Link to comment Share on other sites More sharing options...
Area Representative Piers300 Posted July 13, 2016 Author Area Representative Share Posted July 13, 2016 Unfortunately, the car would not start this evening, so I am back to where I was before. It still starts with a squirt of fuel. Piers Link to comment Share on other sites More sharing options...
L7 FST Posted July 13, 2016 Share Posted July 13, 2016 PiersI really do feel for you... Big disappointment after so much effort and input. Don't let Chapman Cars off the hook...If you finally find a fix, and the weather improves, a Kent Sunday blat (this weekend?) is long overdue! Watch this space.Stephen Link to comment Share on other sites More sharing options...
JNC Posted July 14, 2016 Share Posted July 14, 2016 Piers are you sure your tank is vented properly ? It sounds to me your tank builds a vacuum and when left after you have had it running the tank slowly sucks the fuel back from the rail to the tank, thus won't start next time or reluctantly !. Link to comment Share on other sites More sharing options...
john milner Posted July 14, 2016 Share Posted July 14, 2016 Could the vacuum theory be tested by leaving the filler cap off?Has contaminated fuel in the tank been eliminated? Link to comment Share on other sites More sharing options...
Paul Deslandes Posted July 14, 2016 Share Posted July 14, 2016 Interesting idea re the vacuum slowly sucking the fuel from the line. I would have thought the fuel pump running for a few seconds would replenish it. Does your pump only run for a couple of seconds at switch on and then shut off? If so, have you tried switching on, wait for a couple of secs, switch off and on again a couple of times over. The pump cuts out after a couple of seconds if the engine isn't cranking as a safety measure so might not be priming the rail first time. Not very likely but worth a try, as is taking the cap off after switching off after a run.I would give Steve Greenald a call at Track N' Road and see if he knows of the problem and can fix it with a partial remap. He's remapped hundreds of these cars over the years and will almost certainly be able to sort it.He's only working part time now so may be a bit difficult to contact, but well worth the effort. And not too far from you.07774 773824Paul Link to comment Share on other sites More sharing options...
JNC Posted July 14, 2016 Share Posted July 14, 2016 It sounds a fuel problem to me rather than remap as Piers squirts petrol straight into RB's from cold and it starts first time , the vacuum theory is worth a shot , yes the fuel pump starts and primes up to the injectors but could they have air locked ? Link to comment Share on other sites More sharing options...
John Vine Posted July 14, 2016 Share Posted July 14, 2016 The pump cuts out after a couple of seconds if the engine isn't cranking as a safety measure so might not be priming the rail first time. Yes, that's my understanding too, but does the pump cut out after a given time period or after the correct pressure is reached? Indeed, is the ECU even aware of the fuel pressure?Piers - a few questions: Have you tried starting from cold with the air filter already removed (but before you squirt in petrol)? Are you keeping your foot off the accelerator? Once it starts, what is the idle rpm? JV Link to comment Share on other sites More sharing options...
Paul Deslandes Posted July 14, 2016 Share Posted July 14, 2016 My partial remap comment referred to the possible need to address cranking fuelling. As it seems to run okay once started, provided the ECU firmware has the cranking fuelling feature, it should an easy tweak. It might also be possible to update the firmware if not.JV, the ECU runs the pump for approximately 2 seconds and is a set time rather than pressure sensed. The ECU has no knowledge of fuel pressure or injector flow rate. Once the engine is cranking, the ECU responds to the crank sensor pulses by running the pump continuously so, as long as the line is primed, there should be high pressure fuel available all the time.It definitely sounds to me like too lean mixture. If the ECU doesn't do cranking fuel, a serious increase in low coolant temperature fuelling should help. I had the opposite problem some years ago with my 967 ECU on a 2litre Vx where the cold fuel level was so high that it flooded the engine at start up and, if stopped before it had warmed up, I had to take the plugs out to get it to start again as they were saturated in fuel.Piers, does your ECU wiring loom have a serial data connector spliced into it? If so, are you able to read the ECU with Easimap, albeit you can't see much without the PIN? You should be able to download the ECU file without the PIN, and it might be possible to unlock it and have a look see.Paul Link to comment Share on other sites More sharing options...
John Vine Posted July 14, 2016 Share Posted July 14, 2016 Thanks for that, Paul.I agree with you about the too-lean mixture at start-up. It matches exactly what I've always understood about this model not having cold-start support.Re diagnostic plugs, my old 1999 SS-R (effectively an R300 engine) had one, so I imagine a later "proper" R300 has one as standard. Mine was fitted by CC when they upgraded the car to R spec (replacing the Rover MEMS ECU with an MBE), But I never used it as I wasn't into Easimap in those far-off days! I've sent Piers some info re Easimap, SBD cable and (a possible) ECU PIN. JV Link to comment Share on other sites More sharing options...
Paul Deslandes Posted July 14, 2016 Share Posted July 14, 2016 I'm not sure how similar the cars are but I had Smithy7's (Pete Smith) car here a few months ago and I added the serial connector to his loom as it wasn't already present. If you're just using Easymap without the mapping box you just need two serial wires and ground. Whilst we had Pete's apart I also added the +5V and another ground for the trim box pots in case he took it to Track N' Road. This he did and had it successfully remapped and then, very sadly, had it seize on him, so it's current in for a very expensive rebuild. No fault of the mapping, just too little oil.Piers, if you would like help to do the same I'd be happy to oblige as it's not a job everyone wants to (or even should) tackle themselves. Track N' Road use a breakout cable which plugs between the loom connector and ECU and brings out the serial port, so the loom doesn't have to be modified.Paul Link to comment Share on other sites More sharing options...
Smithy77 Posted July 14, 2016 Share Posted July 14, 2016 Hi Paul,Been reading this thread and have been suspecting cranking fueling/mapping issue too, and then you've made the suggestion on this latest page. If it is such a common problem on R3/400s with MBE's, that would definitely be my next target. In any case, I'd strongly advise getting a comms lead and Easimap for home diagnosis; such an invaluable tool. Track and Road will then be able to talk to and tweak it.Incidentally, after I left TnR I noticed similar symptoms with starting (although they were also present before the visit to a degree), but it did it even with a warm engine. Its a common problem after remapping because, unless you leave the car there over night, they can only have an educated guess at the cold start mapping. Gave them a call and they said no problem to bring it back for a tweak to the cranking map FOC, or they could even do it remotely if I sent them the map file using Easimap - perhaps an easier option for the OP if distance is an issue.I also have the PIN code for a standard 967 MBE if needed. Link to comment Share on other sites More sharing options...
Paul Deslandes Posted July 14, 2016 Share Posted July 14, 2016 Hi Petethis must be a maddening issue to have to deal with but should be sortable one way or another. I looked up how to recover the PIN to remind myself but forgot what PIN we found for yours which, as you say, seems to be common to all of them. Piers will also need access to an XP laptop with integral serial port as, as we found out, nothing else works. It would be interesting to know if Virtual XP running under Windows 7 would also work with the integral serial port.How's your rebuild going? Probably fairer to email me so as not to hijack Piers's thread.Paul Link to comment Share on other sites More sharing options...
John Vine Posted July 14, 2016 Share Posted July 14, 2016 Paul, YHM.JV Link to comment Share on other sites More sharing options...
colindavies56 Posted July 14, 2016 Share Posted July 14, 2016 I had a similar problem with a 205 Fri in the 80s,faulty none return valve,long time cranking as line was empty,fitted a switch from pump to battery,flick on and count to 10 slow,started great,1st time,1st turn.give it a go,mine was a cheap easy and quick fix. Link to comment Share on other sites More sharing options...
Area Representative Piers300 Posted July 14, 2016 Author Area Representative Share Posted July 14, 2016 Just got back from the local East Kent 7 meeting, where true to form, the car failed to start when ready to leave. However a quick squirt of petrol into the T/B's and it started. I went prepared for this to happen.i will answer all questions tomorrow.Thank you everyone for your continued help. Piers Link to comment Share on other sites More sharing options...
Area Representative Piers300 Posted July 15, 2016 Author Area Representative Share Posted July 15, 2016 Your questionsYes, I have tried cold starting with the Pipercross filter removed - no difference.Yes, I keep my foot off the throttle - always have, but once it starts then the throttle can be used.when it starts it idles at around 1000 rpmNo, the wiring loom does not have a serial port that I can find and I don't have any comms cable or laptop with the old XP. Thanks all Piers Link to comment Share on other sites More sharing options...
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