Hybrid_From_Hell Posted November 12, 2006 Share Posted November 12, 2006 Hey ho and Sod it Well, today saw me at Broxhead, seeing if the last of the misfire mods (replace efi harness) had made any difference, The day started well, the Eales burst into life and I whizzed over to mates to pick him up, he commented how the engine seemed to be running ok, and we "RPMd and Grinned" our way to the event. Pulled in, switched off signed on, had a chat, jumped in 90 and.......... MASSIVE misfire time He was as stunned as I was, so, we vanished with the 90 back to his house. 3.5 hours later we had with the aid of a multimeter and spare units, tested just about everything, swapped all major components, and got precisely NOWHERE but with the engine now cold again, the engine had some power, but a slight misfire, we returned to broxhead where it got worse, ....now so bad I wondered if I would make it home without the need the flat bed taxi ? Got home and it is back in the garage................. in real disgrace. So For those that have any ideas please post up, I have about 5x more things I have up my sleeve to do, 3x of which I do not expect to work,........... but will do just so as to be able to say its NOT them. So far we have : Chnaged (for known good units) AFM ECU Resistor Pack, Fuel Pump Fuel Relay Main Relay and Steering relay I have replaced a BRAND new EFI Loom on it New Plugs, Magnecor leads, swapped coil packs, and even taken all the EDIS Megajolt system off and replaced Dizzy Cap Rotor arm, leads Coil Amp Coil and Leads and no difference exactly same misfire Have worked though the RR Diagnostic manual test 1 -16, ie 1. volts to main relay, 2. Volt supply to ECU, 3. volts to Fuel pump via AFM, 4. Volt to ECU Pin 4, 5. Volts to Spped Signal circuit, and fuel shut off swich, 6. Amp, 7. Volts across AFM Pot, 7. AFM Pot and wiribng to ECU, 8. Resistenace OHMS to AFM to ECU, 9. Throttle Pot, 10 OHMS ATS, 11 OGHMS ACT, 11a, OHMS resistance EAV, 13 Resistance CSI, 14. Integrity Injector soleniods, resistor opack, wiring and ECU Connections, 15. Continuity resistance each injector and resistor, 16. OHMS injectors and resistors, 16A and 16B Also have Checked earths, replaced battery, replaced alternator, done new earths from batteries, checked PRV and pump and return, and feed to pump, ignition switch, main feed, fuel feed, and a shed load of other tests swaps and now I am clutching at straws............. The misfire is a biggie now, it was just like say "1 Plug lead missing", now it varies between 1 and several cylinders, and gives me the feeling the engine could die completely, then, for no real reason the engine sorts itself out and is ripping riproaring away.... then again for no reason back to the misfire nightmare I have a few thoughts (other than a box of matches and a gun to my temple) 90s Cut out switch, - Bypass Fuel pump 12V direct powered feed (athough pressure running with MASSIVE misfire saw steady 31/30 PSI) Injectors - swap (I have a spare set of 8x jag injectors - will get checked 1st and swap) Fuel filter - bypass Fuel pump remove inspect replace (but doubt it) Increase pressure in F Rail via PRV - but not expecting it to do it as it CAN run 100% ok ANOTHER Compression Test - when it misfiring Remove every fuse from 90 in turn this is due to one weridity : The fuel pump relay and the Steering pack both show 3v on input and it should be zero, but this just makes the fuel pump run when it should be off, the fuel pump could technically run continously, and that would be fine the pressure in the rail would still be 30PSI and all excess dumped to return in tank, we both think this is nothing to do with the misfire, but who knows, as I said we have changed everything, and the 3v stays... I may have missed something out but : BASICALLY ANYONE ANY IDEAS ? And please "Fit a diesel or carbs and points" I won't appreactite - this is doing me and my mates head it, but if you have an idea squeak now.... VVV Unhappy Nige Quote Link to comment Share on other sites More sharing options...
freeagent Posted November 12, 2006 Share Posted November 12, 2006 cant you speak to Mark Adams about it, i seam to remember you having a trip to his place a little while ago.... ...or fit a Tdi (sorry) Quote Link to comment Share on other sites More sharing options...
general-confusion Posted November 12, 2006 Share Posted November 12, 2006 Hmmm Tough one that....are there any specific conditions that cause the miss ie hot,cold,tilted at an angle ,full of fuel low on fuel etc. Maybe a call to Mark Adams (the V8 Guru) may lead you in the right direction Quote Link to comment Share on other sites More sharing options...
general-confusion Posted November 12, 2006 Share Posted November 12, 2006 Darn someone suggeseted Mark while I was typing !! Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted November 12, 2006 Author Share Posted November 12, 2006 Fuel Full, (tank emptied just in case of water ?.)..nope, does it at any angle it fancies... Mark is going to get a call, ............. Nige Quote Link to comment Share on other sites More sharing options...
LR90 Posted November 12, 2006 Share Posted November 12, 2006 Nice sunny morning but turned damper later (not that it's relavant) On a more helpful note you mention 3v feeds when it should be zero. OK, the items getting the 3v don't care much but it must be worth tracing which item is dud and placing 3v on what should be a dead circuit. Can't be too hard to see what else is on the fuel pump relay and the Steering pack circuit? Quote Link to comment Share on other sites More sharing options...
BogMonster Posted November 12, 2006 Share Posted November 12, 2006 Have you spoken to Eales since he built the engine originally, could it be something to do with the advance/retard you are using on the whizzy new ignition system, since I seem to remember you had problems with the Eales using very "odd" ignition settings when you first did it? Quote Link to comment Share on other sites More sharing options...
will_warne Posted November 12, 2006 Share Posted November 12, 2006 Just a slightly differant idea. Is you're tank breathing propperly? I'm just thinking that something like a sticky (or fitted wrong way round) roll over valve could cause the tank to vacuum and strangle to fuel supply. What do you reckon? Quote Link to comment Share on other sites More sharing options...
Pete Attryde Posted November 12, 2006 Share Posted November 12, 2006 Just a thought but is the coolant temperature sender behaving correctly. As if it is telling the ECU the wrong thing it could cause it to miss fuel the engine and cause a miss fire. Pete. Quote Link to comment Share on other sites More sharing options...
landmannnn Posted November 12, 2006 Share Posted November 12, 2006 If it is not ignition or fuel - which seems to be the case then it could be the other component... air. Could you have an air leak from one of the hoses? When you pull off the hoses the engine either stops immediately or splutters depending which hose. Quote Link to comment Share on other sites More sharing options...
Les Henson Posted November 12, 2006 Share Posted November 12, 2006 Fit a diesel Les. Quote Link to comment Share on other sites More sharing options...
V8 Freak Posted November 12, 2006 Share Posted November 12, 2006 I recommend giving the engine to me, stripped of all the electrickery of course.... You install my vasty underpowered V8 3.5 (Boasting a fabulous 115 BHP...) and see if the misfire goes away! I install yours and see if it runs on my old dizzy and carb !!! Is it a deal ?? Could be an end to your problems !! Neil Quote Link to comment Share on other sites More sharing options...
imspanners Posted November 12, 2006 Share Posted November 12, 2006 Has your megasquirt got a 2nd map on it? If the miss is moving between cylinders, is it due to it running too lean? Ideally changing the mapping or to test it, pop it onto a gas tester and check the emissions.? Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted November 12, 2006 Author Share Posted November 12, 2006 MegaJolt not Squirt, and removing all of this and fitting Dizzy and coil etc makes no difference. Have had a call from Jon White, he has added a number of really reaaly good ideas to add to the "Try" list......... Nige Quote Link to comment Share on other sites More sharing options...
unclebill Posted November 12, 2006 Share Posted November 12, 2006 Fuel Full, (tank emptied just in case of water ?.)..nope, does it at any angle it fancies...Mark is going to get a call, ............. Nige Nige, I won't presume to say anything, but in w. Sussex there is a guy that I've used and don't know if you remember when one of the mags drag raced a defender, well hes the guy that prepared it and my mates series hybrid that also appeared in one of the monthlys, name of Fraser, if you want I can get his number, hes local and really does know his V8's. Good luck Bill Quote Link to comment Share on other sites More sharing options...
MJIbex Posted November 12, 2006 Share Posted November 12, 2006 Nig, Try your cut out switch bypass idea, I've had an issue with mine in the past and a mate had a tempremental one today; although both cause complete engine stop! It's an easy one to try. Mark Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted November 12, 2006 Author Share Posted November 12, 2006 I'll be busy this week cos I really wnated to have a go with andys load cell / winch session, but a the mo the engine is a nightmare,..... Cut out switch is one of the 1st on my hit list Will W - Nope, no prob with fuel tank vacumn /pressures Nige Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted November 12, 2006 Author Share Posted November 12, 2006 Just a thought but is the coolant temperature sender behaving correctly. As if it is telling the ECU the wrong thing it could cause it to miss fuel the engine and cause a miss fire.Pete. Good call, but tested via the diag list and both coolant sender and test was AOK Nige Quote Link to comment Share on other sites More sharing options...
will_warne Posted November 12, 2006 Share Posted November 12, 2006 I'll be busy this week cos I really wnated to have a go with andys load cell / winch session, but a the mo the engine is a nightmare,.....Cut out switch is one of the 1st on my hit list Will W - Nope, no prob with fuel tank vacumn /pressures Nige Thought I'd just check. Its one of those things you might not have thought about.... Quote Link to comment Share on other sites More sharing options...
Bull Bar Cowboy Posted November 12, 2006 Share Posted November 12, 2006 I have been thinking and looking at the diagrams tonight ……………….I will call you tomorrow …………. the 3 volt issue may well be significant … Ian Quote Link to comment Share on other sites More sharing options...
Andy Posted November 12, 2006 Share Posted November 12, 2006 i dont understand the systems, but id be chasing the 3v issue as you cant seem to find anything else at fault. Quote Link to comment Share on other sites More sharing options...
freeagent Posted November 13, 2006 Share Posted November 13, 2006 yep, agree with the others. look for and sort out the 3V issue, i'm not sure how, but something in the back of my mind thinks that it might be playing a part... Quote Link to comment Share on other sites More sharing options...
jwriyadh Posted November 13, 2006 Share Posted November 13, 2006 You need a bit more dynamic testing to isolate the cause of the problem. The 3 volts may be significant particularly if it varies about the 3volt level. None of your testing indicates how much fuel your system is injecting, might be good to watch a Wideband O2 sensor if you have one available. Alternatively have you a meter that can watch the pulsewidth at the injectors. Could probably also be watched by a laptop usng either a scope setup or a recording facilty. If nothing else use an extended meter to watch signals going into the ECU while driving. jw Quote Link to comment Share on other sites More sharing options...
Bull Bar Cowboy Posted November 13, 2006 Share Posted November 13, 2006 The 3 volt on the FPR input is (might be, or could be) significant due to the minor fact that its supply is fed from the Main relay output …………. This supply also feeds the resistor pack for the injectors. The supply leaves as a Brown / Orange and is then divided into three supplies within the loom ………. two go to the resistor pack (to feed the resistors for each bank) and the third feeds the “Hello, I’m open” contacts inside the AFM. Fill in the blanks............ Voltage to earth from, 1) SM Pin 2 2) SM Pin 5 3) MR Pin 87 4) ECU Pin 20 Then also measure the volts to ground with the engine running on BOTH Brown Orange feeds to the molex connector on the Resistor Pack 1) Resisr Pack Molex pin 2 2) Resistor Pin molex pin 9 As most has been changed and it still runs like a bag of plop on either conventional or EDIS ignition, then it must be fuel related. Due to the way in which the flapper operates, the injectors seem the most obvious point of failure. Anything on the injection feed failing before this point will cause the complete loss of 4 pots. Therefore the way forward is to ensure the injectors are getting a good supply voltage and then to start looking at each injector in detail. From your description, the mode of failure points to an injector that is failing as an intermittent short circuit (or very, very low resistance) .......... this will cause others in that bank to have a fit of indifference as to the whether they inject and the injection time. Having looked at the flow rates, you could change the current Jag injectors back to LR flapper types as a short term measure (they would be in the upper end of their operating specs (but OK). Ian Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted November 13, 2006 Author Share Posted November 13, 2006 The 3 volt on the FPR input is (might be, or could be) significant due to the minor fact that its supply is fed from the Main relay output …………. This supply also feeds the resistor pack for the injectors. The supply leaves as a Brown / Orange and is then divided into three supplies within the loom ………. two go to the resistor pack (to feed the resistors for each bank) and the third feeds the “Hello, I’m open” contacts inside the AFM. Fill in the blanks............ Voltage to earth from, 1) SM Pin 2 2) SM Pin 5 3) MR Pin 87 4) ECU Pin 20 Then also measure the volts to ground with the engine running on BOTH Brown Orange feeds to the molex connector on the Resistor Pack 1) Resisr Pack Molex pin 2 2) Resistor Pin molex pin 9 As most has been changed and it still runs like a bag of plop on either conventional or EDIS ignition, then it must be fuel related. Due to the way in which the flapper operates, the injectors seem the most obvious point of failure. Anything on the injection feed failing before this point will cause the complete loss of 4 pots. Therefore the way forward is to ensure the injectors are getting a good supply voltage and then to start looking at each injector in detail. From your description, the mode of failure points to an injector that is failing as an intermittent short circuit (or very, very low resistance) .......... this will cause others in that bank to have a fit of indifference as to the whether they inject and the injection time. Having looked at the flow rates, you could change the current Jag injectors back to LR flapper types as a short term measure (they would be in the upper end of their operating specs (but OK). Ian I have a spare set of JAG injectors, I'll get them fully checked out 1st before fitting.. I will have a study and be back to you re the above Cheers mate Nige Quote Link to comment Share on other sites More sharing options...
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