Hybrid_From_Hell Posted October 15, 2006 Share Posted October 15, 2006 RIGHT "Not Happy" would be an understatement. I have had a "on and Off" Misfire on the V8 now for some weeks, and its getting worse............... The symtoms were at 1st that this misfire only appearred when the engine was serious hot, now its got worse ..............and did it today when I satrted it from cold just to pop it back into the workshop after I had been wiring the fans. The misfire seems like 1 plug lead has been pulled off. In the past NOTHING I did seemed to sort it, then once it has cooled down it was fine - sometimes for ages, when its fine it does goes like the proverbial, .............but this F misfire is now doing my head in. For those who don't know the spec of the engine is : 4.5 Eales Race V8 Rebuilt last year, just about everything new EDIS and MegaJolt EFI Flapper hybrid system, ..............and yes is still misfires on the old coil rotor arm and leads. New Magnecor leads, new coil packs, plugs, and just about everything you can think of Could it be an injector ?... if so what are the symtoms, ? at the mo if I hold it stationary at say 3500 I get a popping and a 'banging' as it seems to want to clear - but it didn't Sometimes I can start it and drive 100 miloes ..........no probs, ........... other times it starts and runs with this misfire irrespective what I do to it. Have changed AFM ECU Coolant sensor, Plugs, Coil Packs, Pug leads, Resistor pack, fuel pump, fuel pressure, compression test PRV, .............and many more items too that I can't think of right now so ideas ? Next weekend I am going to get very "Serious with its A**e after old sodbury with a multimeter and diag Manual, but the prob often is its fine and therefore no fault to track, it does seem to be getting worse, so ideas please ? Nige Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted October 15, 2006 Share Posted October 15, 2006 Borrow an oscilloscope and an X10 probe and look at waveforms from coils/injectors/pickups etc. might show things up that you wouldn't see with a meter. Yes I do own a scope... Quote Link to comment Share on other sites More sharing options...
Bull Bar Cowboy Posted October 15, 2006 Share Posted October 15, 2006 Try changing No1 injector ............. its very difficult to tell the difference between fueling missfire and HT missfire............... sometimes you can see HT missfire on a rev counter. Ian Quote Link to comment Share on other sites More sharing options...
Jon White Posted October 16, 2006 Share Posted October 16, 2006 Twin Su's.......I get no problems with misfires!!! :-p Jon Quote Link to comment Share on other sites More sharing options...
Tonk Posted October 16, 2006 Share Posted October 16, 2006 funny that, i've been playin with v8 over weekend with su's on it, runs like a sewing machine now, it hasn't been raining though Quote Link to comment Share on other sites More sharing options...
jules Posted October 16, 2006 Share Posted October 16, 2006 This may be stupid but every V8 fault I have had has come from a doggy earth somewere... do you have a rev counter as they have been known to cause troubles on injected racers before..(don't ask me how) Alternator working ok (mates TVR has been playing up for the last two weeks and it was alternator / main fuse causing it..still started and drove fine just played up mid revs) have you checked the throtle pertenchiometer for intermitant fault (sorry about the spelling and very long shot) You know more about V8 than I do but a fresh perspective sometimes helps.. Quote Link to comment Share on other sites More sharing options...
white90 Posted October 16, 2006 Share Posted October 16, 2006 Best just get a decent 300TDi fitted and save your self all the troubles you get with this silly V engine PS was it raining/near a puddle/bottle of Evian or had you sneezed any time near the car when the problem developed? if there is a yes to any of these I may have identified the problem. Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted October 16, 2006 Author Share Posted October 16, 2006 Nige Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted October 16, 2006 Share Posted October 16, 2006 Best just get a decent 300TDi fitted and save your self all the troubles you get with this silly V engine Rather an annoying little misfire than a constant annoying bl**dy clattery racket... Quote Link to comment Share on other sites More sharing options...
jules Posted October 16, 2006 Share Posted October 16, 2006 Rather an annoying little misfire than a constant annoying bl**dy clattery racket... Developing a smoky tail draft and rattles like a bucket of old nails. also keep getting overtaken by old ladies in nissan micra's I should imagin a pace of life that slow is nice at times Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted October 16, 2006 Share Posted October 16, 2006 Bit like Fred Dibnah in his traction engine - holding all the traffic up, clouds of smoke, quaint old fashioned technology, weighs tonnes and has about 5 horsepower, lots of chuffing, clanking and banging but not much forward progress Quote Link to comment Share on other sites More sharing options...
GBMUD Posted October 16, 2006 Share Posted October 16, 2006 The funny thing is that, for the most part, and in my experience, V8 drivers cannot afford to go as fast as diesel drivers. Chris Quote Link to comment Share on other sites More sharing options...
jules Posted October 16, 2006 Share Posted October 16, 2006 The funny thing is that, for the most part, and in my experience, V8 drivers cannot afford to go as fast as diesel drivers. Chris To shay (if you can't afford one don't have one) Nigel We're not helping much are we Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted October 16, 2006 Author Share Posted October 16, 2006 In a word NO MR BBC has phoned me, and an agreed plan is forming Nige Quote Link to comment Share on other sites More sharing options...
will_warne Posted October 16, 2006 Share Posted October 16, 2006 In a wordNO MR BBC has phoned me, and an agreed plan is forming Nige Fitting a diesel???? My coat? Why thank you... Quote Link to comment Share on other sites More sharing options...
Bull Bar Cowboy Posted October 16, 2006 Share Posted October 16, 2006 Hmmmmm … diesel has its place, usually in tanks at your local garage …….. when it is allowed out, its usually used in tractors and other slow moving clumsy machinery. Lets just say that the possibility of the misfire being HT related looks remote at the moment. The area currently under scrutiny is the injector feeds from the resistor pack. Any problem before this point would cause misfire of a bank (4 cylinders) , so a single pot has to be post the resistor pack. Where as most of us have a gauge on the dash ……… Nige uses his left ear as the rev counter. The standard inductive loop rev counter is good for diagnosing HT related missfire as when a misfire occurs the back emf is usually higher with a spiky ringing waveform and the rev counter tries to keep up with it by swinging widely all over the place……….. when the misfire is fuel (injector) related the rev counter behaves as normal because it is seeing all the sparks…….. and muttering ‘no problem ere guv’ So I think tonight, Nige maybe spending a little time carefully looking at the EFI loom from the resistor pack forwards. No tools required here ……….. most electrical (and a considerable number of electronic ) faults are detected by observation ……… looking for a small area of loom damage, or cracked brittle wires where the injectors connectors go back in the loom ………..or damage where the resistor pack meets the main loom. At the moment I strongly suspect there may be some small damage to the loom in the vicinity of the AFM / Resistor pack ………… as Nige has noted anther symptomatic clue in solving the puzzle. The story is just beginning …………..my experience tells me the damage / problem is usually in the most inaccessible place known to man …… and you normally need to be a dwarf on crack with 12 inch fingers to effect a repair ……… Ian Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted October 16, 2006 Share Posted October 16, 2006 I'm guessing you've probably already mentioned this to Nige or discounted it, but what about opening the resistor pack & checking the tracks in there? They do seem to fill with mud Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted October 16, 2006 Author Share Posted October 16, 2006 Got home early today, real treat - so I thought I would see about tracking down that damned misfire which is had when I reeversed it back into the workshop. AND Misfire has vanished again, no amount of jiggling various wires and sensors had any effect, so stumped until it does it agin - which of course will be at the most inconvienient time / or when playing with it REALLY REALLY Hacked off..................... What on earth can have "Sorted itself" from JUST reversing it into the workshop and leaving overnight went in cold came out cold and rang beatuifull, blast around the lanes just made me grin but I know its still in their somewhere. Maybe it heard me talking about replacing its EFI Loom Kin Electrics. Mind you the fans work a treat......... Nige Quote Link to comment Share on other sites More sharing options...
Andy Posted October 16, 2006 Share Posted October 16, 2006 lectrics are the work of the devil, kill a chicken & run backwards round the LR three times chanting the timeless chant 'praise be to the great god lucas' Quote Link to comment Share on other sites More sharing options...
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