solstice Posted December 13, 2014 Share Posted December 13, 2014 Guys, any ideas? We have fitted a vvc head ecu and other necessary bits to my 1.8 k, it starts and runs great but has an intermittent probelem where it seems to be running on 2 cylinders, the last time it happened I pulled over stopped the engine, restarted it after a couple of attempts and it ran fine, I'm assuming it is probably electrics, any suggestions? Link to comment Share on other sites More sharing options...
revilla Posted December 13, 2014 Share Posted December 13, 2014 If it really is loosing two cylinders, and they appear to be two cylinders equally spaced (i.e. it runs reasonably evenly and seems to be doing bang-miss-bang-miss rather than a very lumpy bang-bang-miss-miss) then I'd be looking at the coil packs and wiring. Is it EU3 with coils on top of the head? If so you must have switched tp the longer red-tip coils for the VVC head and one of them could be dodgy, or you could have a wiring problem. I'm assuming here that you DID switch to the longer VVC-specific coils; if you didn't they wont be long enough and if the contact the plugs at all they won't engage properly and that could be the problem! Link to comment Share on other sites More sharing options...
solstice Posted December 13, 2014 Author Share Posted December 13, 2014 Yep it is eu3 and we used the coils from the donor car (which seemed to drive ok, but as this is intermittent it may have been pre existing) any idea of the cost of replacement coil packs? Link to comment Share on other sites More sharing options...
SM25T Posted December 13, 2014 Share Posted December 13, 2014 You can get them from a motor factor. Make sure you get one for VVC engine as it is an inch taller. Before purchasing , check primaries with engine running to see if two are cold. Swap coil packs over and see if you have moved the cold primaries over to the other two. Link to comment Share on other sites More sharing options...
solstice Posted January 3, 2015 Author Share Posted January 3, 2015 Guys, a quick update, it seemed to be caused by a dodgy earth, there were a couple of minor electrical gremlins that pointed us in that direction. We then had an issue with the car not starting when hot, the positive lead to the starter motor was knack erred and replaced but the problem persisted, eventually bit the bullet and fitted a new battery, happy days problem solved ( although still not sure why the battery had enough guts to start the car cold but not hot!)what a difference started with a 120 road sport and now have a 170 road sport ( I had the ecu remapped and de immobilised by mark at z&f and the first time we ran it. You'd swear it had been fitted with a lightened flywheel the revs rise and fall much quicker than before the ecu was modded)bit of a handful on damp roads though! Link to comment Share on other sites More sharing options...
revilla Posted January 3, 2015 Share Posted January 3, 2015 As shown in this graph:http://www.vias.org/eltransformers/img/lee_electronic_transformers-153.gifThe resistivity of copper rises rapidly with increasing temperature. Guestimating from the chart, copper coils (e.g. both the starter solenoid and the starter motor windings) will have (1.14/0.94)=1.21 times the resistance at 60C than they do at 10C. This increased resistance equates to a drop in current drawn. The exhaust primaries are very close to the starter and tend to wrap around it which can lead to very high temperatures especially when standing for a short while after a hot run. A "weak" battery will have a higher internal resistance, compounding the problem, leading to poorer hot starting. This is the main reason why the K-Click manifests itself more strongly on a hot engine, when the added resistance in the solenoid just compounds any number of other potential electrical and mechanical resistances and tips an already compromised system over the edge.I also have a 1.8 VVC and I know just what you mean about the Z&F remap; it's very hard to put into words what it does to the engine and to be honest, comparing the power gain claims with the amount of headwork Oily claims is needed to achieve similar results I'd take them with a pinch of salt, but it certainly does sharpen things up and make the engine feel that much keener. The only way I can think of describe it on mine is like this; some engines seem to have a "sweet spot" RPM where the car just feels ready to jump when you touch the throttle, and where you want to be when preparing to overtake - since the remap mine feels like that right through the rev range! I'd certainly recommend it and wouldn't want to go back to the standard map now. Link to comment Share on other sites More sharing options...
Member Jonathan Kay Posted January 3, 2015 Member Share Posted January 3, 2015 And why it saves so much time to measure the battery voltage at rest, idle and during cranking. This comes up repeatedly. So why the reluctance*? I can guess at two possibilities: the cost of a multimeter (around £12) and lack of familiarity with how to deploy it in combat...Glad it's all fixed.Jonathan* :-) Link to comment Share on other sites More sharing options...
solstice Posted January 4, 2015 Author Share Posted January 4, 2015 Thanks, that's interesting, particularly the temperature, I've got some logging equipment at work, think I will strap a sensor to the started motor and see what sort of temp it gets to.i did measure the battery voltage when the engine was off and running and it looked fine, didn't measure it when cranking though. Link to comment Share on other sites More sharing options...
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