Area Representative Nick Bassett Posted April 9, 2019 Area Representative Share Posted April 9, 2019 Since acquiring my SLR, it has been a pig to start from cold, but it does a very strange thing that I'm trying to understand... let me explain!BackgroundIt's a standard year 2000 SLR, but runs off an Emerald K6 and verniers used to set up cams. KV6 TBs. When I first got it, I took it up to DVA who gave it a thorough going over including balancing the TBs to ensure the right amount of air is going into it. All cam timing is perfect. The map is a good SLR version, supplied by DVA.Starting from coldIt cranks and cranks and cranks and cranks... then eventually it will fire, but it will not idle and runs a bit roughly and I cannot take my foot off the throttle, otherwise it will die. I can drive off with it like this, but it's hardly ideal. If and when I do drive off immediately, eventually after a few miles, it will idle OK and all will be well.That strange thing I mentioned earlier?If after I have started it and run it for a minute or so with my foot on the throttle and then let it die, I sometimes leave it for a few minutes switched off. If I then return and crank it over again, it will idle perfectly on it's own, foot off the throttle, in the way that it should do! However the engine is still cold, but it runs just fine.So, I'm trying to understand why it does this - something must be causing it, but I can't think what! The black sensor thing (can't remember it's name, but checks air temp I think?) was checked by DVA and was working OK.I should probably take it to be mapped, but thought I would ask here in case it is something obvious. Once the car is running it is fine and when hot pulls like a train.Can anyone help or suggest anything please?Thank youNick Link to comment Share on other sites More sharing options...
Area Representative Nick Bassett Posted April 11, 2019 Author Area Representative Share Posted April 11, 2019 No thoughts from anyone on my cold start issue? Very unusual for blatchat!Car did it again today - took it for it's first post Winter blat - the first drive for > 4 months - I'm always absolutely blown away by the performance... these cars shouldn't be legal, but I'm bloody glad they are! Dry sump oil pump refresh seemed to go OK too - great oil pressure and no leaks. Roll on the Taffia fish n'chip run... Link to comment Share on other sites More sharing options...
CageyH Posted April 11, 2019 Share Posted April 11, 2019 Do the KV6 throttle bodies use an IACV?If it was me, I would make sure that my throttle position sensor was correctly set in the Emerald. I would also look at the fuel settings for cold air and coolant, making sure that the mixture was suitably enriched.I would start my car with the ÉCU hooked up to a laptop/PC and makes sure that the ÉCU was seeing the correct/sensible temperatures as the car warms up.My VHPD engine on Jenveys fires quickly no matter what temperature it is, and idles correctly. Link to comment Share on other sites More sharing options...
CageyH Posted April 11, 2019 Share Posted April 11, 2019 Just to add, if it does have an IACV, I would start there. Link to comment Share on other sites More sharing options...
rj Posted April 11, 2019 Share Posted April 11, 2019 Is your throttle pot set up correctly?If you have a wideband lambda datalogger you could power it up from an external power source so that it's ready to log when you fire up the engine. This could give useful data.You can always, if you don't have the IACV try to fiddle with the ignition timing at idle when cold. Link to comment Share on other sites More sharing options...
oilyhands Posted April 12, 2019 Share Posted April 12, 2019 In my experience, using a little more air through the TBs and commensurately less ignition advance at idle greatly improves cold start provided idle stabilisation using timing is configured and enabled, try cracking the throttle open a little, realign the throttle pot and reduce idle advance at 1000 to zero. Link to comment Share on other sites More sharing options...
Area Representative Nick Bassett Posted April 12, 2019 Author Area Representative Share Posted April 12, 2019 Thanks Oily - how do I realign the throttle pot?Any idea why after being left a few minutes after the initial start it'll fire straight off and idle perfectly? Link to comment Share on other sites More sharing options...
oilyhands Posted April 12, 2019 Share Posted April 12, 2019 Use ‘throttle position sensor ‘ from the ‘setup’ menu and follow the instructions. After a couple of minutes the startup corrections will change and the burn will be much faster. This is much more likely to keep the engine alive.Oily Link to comment Share on other sites More sharing options...
Area Representative Nick Bassett Posted April 12, 2019 Author Area Representative Share Posted April 12, 2019 Thanks Oily Link to comment Share on other sites More sharing options...
Nigel Riches Posted April 15, 2019 Share Posted April 15, 2019 Hi Nick.I posted here awhile ago about an issue with Emerald ecu and engine temps, had no replies, not like Blatchat of old. I found that the physical temp of the sensor was 70c, but the ecu was showing 95c on the live adjustments screen.I suspect the coolant temp sensor is out of whack, I carried out a temp vs resistance check and at 0c the readings where fine, however as temp increased the error between the expected and actual resistance increased, so, at 96c the resistance that the ecu would read was equal to a temp of 110c, the ecu was doing whatever it is designed to do at those temps, but of course the engine is not that hot, so an engine running poorly. I await a response from Emerald about my findings.I have tried to run the engine without the temp probe connected and encountered a reluctance to start, and when it did eventually fire, what a bag bolts, couldn't go near the throttle as it would die, this was probably due to the ecu trying to control fueling and ignition advance without the temp input, after several minutes as the engine warmed things got better to a point but then deteriorate to a rough running, I had wired the engine fan to switch from thermo switch in the thermostat housing, this a 93 on 87 off VW item, but I think the 92c stat is to hot for this set up, as eventually the fan ran continuously, and the engine ran poorly. Gawd, give me back the old Webers, none of this electricary jiggery pokery.Hope some of this may help you, seems most folks aim their first shots at the throttle pot, but their are other things at play here.Nigel. Link to comment Share on other sites More sharing options...
Area Representative Nick Bassett Posted April 23, 2019 Author Area Representative Share Posted April 23, 2019 OK thanks Nigel.I need to connect the software to the car, but my new laptop doesn't have the right 'male' connector - is there an adaptor I can buy? Link to comment Share on other sites More sharing options...
Sim Posted April 23, 2019 Share Posted April 23, 2019 Emerald will sell you Easy-sync USB to Serial AdapterSKU:01-007from here regards Simon Link to comment Share on other sites More sharing options...
Leadership Team SLR No.77 Posted April 23, 2019 Leadership Team Share Posted April 23, 2019 As posted by Sim, it’s worth buying the one from Emerald because not all USB adapters appear to work.Stu. Link to comment Share on other sites More sharing options...
Area Representative Piers300 Posted April 23, 2019 Area Representative Share Posted April 23, 2019 I had a real problem with starting my R300 from cold. In fact, it would not fire at all when cranking, but would start and run immediately, if I squirted fuel into each throttle body. This turned out to be a bad earth on the ECU, plus cleaning all the major earth connections dramatically improved the battery voltage dip on cranking, which helped the ECU fire the injectors. It may not be your issue, but cleaning all the main earths will hopefully help.Piers Link to comment Share on other sites More sharing options...
Area Representative Nick Bassett Posted April 24, 2019 Author Area Representative Share Posted April 24, 2019 Thanks all - will contact Emerald for that lead.Piers300 - thanks - will check the earths as mentioned. I also run a Brise starter, but heard from a friend that they can cause a voltage drop when cranking! Link to comment Share on other sites More sharing options...
7 wonders of the world Posted April 27, 2019 Share Posted April 27, 2019 Emerald lead and adaptors are perfect, I have tried two other adaptors and neither worked. Link to comment Share on other sites More sharing options...
nickh7 Posted April 28, 2019 Share Posted April 28, 2019 Nick , does it have a kill switch? Could it be that it’s forgotten it’s throttle position? I know it’s different but I’ve a Kmaps EU3 ECU and that can be a poor starter if I don’t to the throttle pump thing after the kill switch has been taken out . Just an idea Link to comment Share on other sites More sharing options...
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