murph7355 Posted June 14, 2002 Share Posted June 14, 2002 The saga is too upsetting to go into at any length, but if anyone has any ideas I'd be most grateful for input... At idle my k-series (big valve head, MBE 967 ECU) cuts out very abruptly and seemingly at random. Sometimes it'll sit there for a few minutes before doing it, at others it only lasts a few seconds. The current opinion is that the injectors are possibly too large (sorry, don't know the flow rate at this moment in time) and so are barely open at idle. Does this sound feasible? Another theory is that the crank sensor is buggered (but I believe this has now been ruled out - not working on it personally as you've no doubt gathered). Hardly anything else has changed other than the engine being removed for a rebuild and an "upgraded" fuel regulator being installed. Needless to say it never did this before. Realise there's not much to go on here, but was wondering if anyone had come across this sort of problem before? I can get hold of any info required if it helps. Link to comment Share on other sites More sharing options...
Dave H Posted June 14, 2002 Share Posted June 14, 2002 Andy, I'm not a K or fuel injection person (Zetec on Carbs), but I would start looking at the bits that have been changed first. Is the "upgraded" fuel regulator set up properly? If it's allowing too much fuel through, could the engine be flooding at idle? Dave H Link to comment Share on other sites More sharing options...
murph7355 Posted June 14, 2002 Author Share Posted June 14, 2002 Cheers Dave. My sentiments exactly. Link to comment Share on other sites More sharing options...
Peter Carmichael Posted June 14, 2002 Share Posted June 14, 2002 Andy, The injectors have a latency that means that the first few milliseconds of current flow don't result in any fuel delivery. If you have increased the fuel pressure, you might have had to trim the map so that the injectors are ectuated less and less and there is an abrupt cutoff where eventually no fuel will be delivered. The injector latency also depends on voltage. Most ECUs have a compensation, so if the voltage was dropping slightly the injector firing time would be increased - if this is not set up on the MBE then as voltage fluctuates you could suddenly stop getting fuel. It would be worth checking all the earths and crimping tight any power connections to the engine loom. Run a booster battery also and see if that keeps it alive. Peterid=teal> 253 BHP K-seriesteeth.gif, no gearboxbum.gifid=red> Link to comment Share on other sites More sharing options...
murph7355 Posted June 14, 2002 Author Share Posted June 14, 2002 Thanks PC. I'll pass the info on. I *think* a booster battery has been used already so that probably rules that out. The only things I can see it being are the injectors, pressure regulator or something amiss with the loom after the engine was taken out/put back in. Bloody frustrating whatever it is. Link to comment Share on other sites More sharing options...
Peter Carmichael Posted June 14, 2002 Share Posted June 14, 2002 On a standard car, the power connection between the vehicle loom and the engine loom is via a spade connector (brown to purple wires). I have had experience of these spreading and giving intermittent connection - the engine dies immediately. All you need to do is crimp the spade terminals together a bit tighter and prevent the joint from flexing by tywrapping each half to something substantial - like the main trunk of the loom. Peterid=teal> 253 BHP K-seriesteeth.gif, no gearboxbum.gifid=red> Link to comment Share on other sites More sharing options...
V7 SLR Posted June 14, 2002 Share Posted June 14, 2002 Andy, thanks for update on the dry sump. Regarding your current problems, where is the car? Would there be any worth in trying a standard set of K injectors or an Emerald M3DK just to see if we can rule out one component or another? I'm sure there are people local enough to the car to be able to drive there in their Caterham and temporarily swap over some parts until you manage to isolate the offending item. Link to comment Share on other sites More sharing options...
murph7355 Posted June 14, 2002 Author Share Posted June 14, 2002 Cheers Nige. The car's actually at a Caterham agent at present. I'm hoping they're going to get the injectors swapped back soon and I believe MBE are being asked to take a look to. PC - wouldn't a loose connector like this cause it to cut out at any point in the rev range? It only does it at idle...will get it checked though. Link to comment Share on other sites More sharing options...
Peter Carmichael Posted June 14, 2002 Share Posted June 14, 2002 Just had the thought that I run my idle settings with a gentle ramp on the fuel so that if the speed drops away the fuelling picks up. This helps the ECU modulate a rock solid idle. What it means is that mine won't just cut out dead. It will struggle to stay running - it means I can creep away from standstill without any throttle if I am very careful with the race clutch. This sounds different to your sudden dead as a doornail symptoms. Don't know what to suggest apart from a thorough audit of what is going on inside the MBE. Peterid=teal> 253 BHP K-seriesteeth.gif, no gearboxbum.gifid=red> Link to comment Share on other sites More sharing options...
CHRIS CLARK Posted June 14, 2002 Share Posted June 14, 2002 Hope you find the problem soon Andy. I suspect this regulator too. Peter C. Ain't that purple/brown loom wire a pain! Had lots of hassle here 'till I discovered it. Good anti-theft 'cutout' though!!!! Link to comment Share on other sites More sharing options...
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