philwaters Posted June 28, 2006 Share Posted June 28, 2006 Ok - so my joyful post last Friday about curing my misfire might have been a little early here. Last night it was back, although it was still better to drive than before. Last night in a dark garage I would again see some small arcing on the leads when I provoked them with a screwdriver and then some around the exit from the plug channel without any provocation (see point 2). I have three ideas: 1. The HT leads I bought were cheap rubbish and / or I have a faulty set. (only £18 and I've never heard of the brand) 2. The plug cover (cast alloy) I have pinches the cables where they come out of the plug channel. I didn't fit this on Friday as I wanted to get out and test it. I refitted it on Monday evening before last nights blat. It could have damaged the leads? 3. My coil is duff and is putting out too-high-a-voltage for the leads to cope with? So... can a coil pack damage a set of leads in anyway? I have a decent set of leads coming today I hope and I want to test them, but I don't want to risk damaging them. It has been suggested I check the coil pack itself for cracks around the posts - thanks Bill, but I'd have thought that would only give local arcing around any crack. Anyone care to share their thoughts, comments and experiances with this kind of thing? Feeling a bit down at the moment as I thought I'd cracked it. ☹️ Phil Waters Link to comment Share on other sites More sharing options...
philwaters Posted June 28, 2006 Author Share Posted June 28, 2006 Guess that is a no then Phil Waters Link to comment Share on other sites More sharing options...
F355GTS Posted June 28, 2006 Share Posted June 28, 2006 Phil can't imagine a coil will damage the leads, I suspect your £18 ones were just cr4p. Mark Link to comment Share on other sites More sharing options...
philwaters Posted June 28, 2006 Author Share Posted June 28, 2006 cheers Mark - I got my decent leads tonight (used on one of my wifes firms race engines - and they supply a well known lead manufacturer with their custom sets apparently) and I am getting the same. I am now starting to think it wasn't the leads... My attention is next going to focus on the coil and maybe a section of my wiring... Now - if we could just get the sumer put on hold while I sort this out... no one would mind would they? Phil Waters Link to comment Share on other sites More sharing options...
Unclefester Posted June 29, 2006 Share Posted June 29, 2006 Tough one....aren't intermittent electrical probs the pits? Strange that you should be able to see external arcing though if it's actually something other than leads/plug caps....definitely not an ignition sender problem? I recall someone on the Scorpion forum had a big ignition problem recently and it was the Hall sender but I dunno what system is used to trigger the pulse on the Rover K. Good luck ❗ NICE PLATE!!! 😬 😬here *eek* Link to comment Share on other sites More sharing options...
NevDyson Posted June 29, 2006 Share Posted June 29, 2006 Phil, Not want to state the obvious but have you check your dizzy cap for cracks or the centre sprung contact ? If there is a hairline crack that may not be visible to the eye , there is a risk that the electrical currant will track through tthe cap either giving an extremely weak spark on one or more cylinders or at worse actually sparking a plug out of sequence. You might also experience no misfire on the engine if only revving in neutral, but a misfire becoming apparant when the engine is under load. I doubt it is the coil as they will tend to give up the ghost completely, and it would be quite easiy to meassure the output from it anyway. What engine is this in relation with by the way ? Good Luck Get In , Sit Down, Shut Up, Hang On. :-) Working next door to Caterham Cars is getting expensive ......... Link to comment Share on other sites More sharing options...
philwaters Posted June 29, 2006 Author Share Posted June 29, 2006 It's a Zetec, with wasted spark coil pack. The crank pickup might be at fault, but I don't think so as you can drive through a problem rpm and the engine is then fine, very smooth. It doesn't feel like signal noise... hoping to see a friend this weekend for some help as I am starting to go round in circles - need some fresh eyes I think (not to mention brains!) Phil Waters Link to comment Share on other sites More sharing options...
F355GTS Posted June 29, 2006 Share Posted June 29, 2006 Phil On a VHPD (Jonhills I think) he had a similar problem (I think in the end it was with the master switch) we moved the Alternator charge lead from the back of the starter directly to the battery and all was fine Mark Link to comment Share on other sites More sharing options...
philwaters Posted June 29, 2006 Author Share Posted June 29, 2006 Interesting - I hadn't considered that. The ECU and my igniton module (that drives the coil) get their power from the key switch which comes from the master switch.... any way to test them other than replace? Not sure about my charging lead - I can't remember it going to the starter - I'll have a look tomorrow night - time for bed now. Phil Waters Link to comment Share on other sites More sharing options...
NevDyson Posted June 30, 2006 Share Posted June 30, 2006 sounds like it could be the crankcase position indicator, they are were always a problem on the mondeos with the 2.0 l zetec. Get In , Sit Down, Shut Up, Hang On. :-) Working next door to Caterham Cars is getting expensive ......... Link to comment Share on other sites More sharing options...
Cloud 9 Posted June 30, 2006 Share Posted June 30, 2006 I had a misfire on my zetec which turned out to be the ECU deciding the engine was too hot and would induce an sort of rev limiter effect , Steve Greenuald at Road and Race turned up the setting and hey presto no more misfire Edited by - Cloud 9 on 30 Jun 2006 17:10:54 Link to comment Share on other sites More sharing options...
Harry Flatters Posted June 30, 2006 Share Posted June 30, 2006 Now - if we could just get the sumer put on hold while I sort this out... no one would mind would they? Now you just know that would suit me down to the ground as well 😬 Hope you get it sorted Phil once and for all *arrowright*Harry Flatters *arrowright* AKA Steve Mell - Surrey AO and Su77on Se7ener Edited by - Harry Flatters on 30 Jun 2006 17:56:33 Link to comment Share on other sites More sharing options...
Peter T Posted June 30, 2006 Share Posted June 30, 2006 Does your ECU have internal coil pack drivers? If it has and you have them switched on then this could cause you the problems that you have. When does the mis-firing happen? Low rpm? high RPM ? under load or not? I doubt it is your leads. Is the crank sensor wiring away from any electrical interferrence? Is it using a shielded earth, if so have you connected this to the ECU? Are you sure that your mapping is not to blame? A lean mixture in that rev range could also be causing the problems. It could be fuel related and not electrical. Is your fuel pump man enough fo the flow and pressure? Is your wiring to the fuel pump/ relay all ok? Check to see if your ECU is earthed via its body, some ECUs need at least a 15 amp earth!! R500 Mango Madness Link to comment Share on other sites More sharing options...
Peter T Posted June 30, 2006 Share Posted June 30, 2006 PS...................don't put summer on hold. R500 Mango Madness Link to comment Share on other sites More sharing options...
elie boone Posted June 30, 2006 Share Posted June 30, 2006 This may sound stupid but have you checked the gap on the sparkplugs ? Link to comment Share on other sites More sharing options...
philwaters Posted June 30, 2006 Author Share Posted June 30, 2006 Thanks for the list Peter! Hottest weekend of the year so far in the garage then Does your ECU have internal coil pack drivers? If it has and you have them switched on then this could cause you the problems that you have. Nope - it is set to drive a Ford EDIS ignition module. All it does is tell it the advance required. The EDIS module then does all the clever working out of when to fire the coils. When does the mis-firing happen? Low rpm? high RPM ? under load or not? It is mostly middle'ish throttle application, under load. Light throttle it seems happier, but even cruising at the right rpm spot will give regular misses. I doubt it is your leads. Good - I've spend enough on them now Is the crank sensor wiring away from any electrical interferrence? It is in a crowded area. I have enough slack, so I could try to move it a bit. Is it using a shielded earth, if so have you connected this to the ECU? It is shielded and it is grounded to the EDIS module which reads the signal before passing it back to the ECU (which is also grounded). The EDIS is grounded directly to the battery. Are you sure that your mapping is not to blame? Don't think so. I have a wideband readout in the car - I can see what the mapping is doing and I also have a target AFR map that the ECU corrects to. If it was fueling I wouldn't get pro-longed misfiring as the ECU would sort it out if was wrong, but it is far out now. A lean mixture in that rev range could also be causing the problems. It's ~14-13.6 AFR It could be fuel related and not electrical. I'm confident it is (fatal statement that!) Is your fuel pump man enough fo the flow and pressure? Yep - JPE spec pump, fed directly off the battery via a relay driven from the ECU. Is your wiring to the fuel pump/ relay all ok? Yep - fat 27amp! Check to see if your ECU is earthed via its body, some ECUs need at least a 15 amp earth!!thumbs up Has it's own fat cable soldered to the PCB, which is then fed out to the scuttle where it meets the EDIS and is taken directly to the battery. I am wondering if it could be the power to the coil pack though. I am going to try adding a relay for that so that it can't be short of power! Crank sensor - interesting. Any idea how to test? Doesn't it put out a sqaure wave that I'd need a scope to test? I will get it cracked. Apart from this it runs great and pulls like a train. I need some wider rear tyres Problem is I only have a short while to sort it before I miss the chance to take a really nice Norwegian customer out - he's a car nut and would love it. I'm starting to think I'll just have to explain and see if he notices (not sure a passenger would) Phil Waters Link to comment Share on other sites More sharing options...
Peter T Posted June 30, 2006 Share Posted June 30, 2006 What wideband system are you using? Does it convey using 0-5 volts output? Are you sure that your ECU can respond to instant Lambda changes? Even Pectel and Motec are not that good at self Mapping!! And can only map as good as the information they receive. So if your readings are not instant then the ecu is always wrong in Steichomatic effeciency. Some CPS can sometimes miss reading a trigger wheel, what teeth pattern have you? and are they standard ford arrangements? R500 Mango Madness Link to comment Share on other sites More sharing options...
philwaters Posted June 30, 2006 Author Share Posted June 30, 2006 Wideband is a Techedge, 0-5 linear input into the ECU. The calibration was carried out when I got it. My map was mostly rich (low 13's) and I am now starting to lean off bit by bit - safer rather than sorry! The ECU will adjust the mixture at set ignition cycles (I tell it how many to pause for) and with Autotune switched on the laptop it then adjusts my map accordingly - within a % limit to avoid making changes too quickly - so you have chance to do something if you've messed up. My target map is conservative - low 14's for low throttle/cruising and them stepping through to ~13:1 for max throttle - this seems to suit the Zetec, any richer and it feels fluffy. It isn't instant responce I'll grant you, but I still get the miss holding a constant throttle on some duel carrigeway and the ECU having had loads of time to home in on a sensible AFR. the CPS is standard Ford which was fine on the old ECU - triggering off of the Ford pattern on the flywheel... Don't think it is that, although the sensor might have packed up I guess. Phil Waters Link to comment Share on other sites More sharing options...
Peter T Posted June 30, 2006 Share Posted June 30, 2006 Change sensor to eliminate then, this way you will have a better starting point. I have a proffesional lambda sensor that is easy to use if you want to borrow. R500 Mango Madness Link to comment Share on other sites More sharing options...
philwaters Posted June 30, 2006 Author Share Posted June 30, 2006 Thanks Peter, I'll try to call Ford in the morning - might even have one in stock - of course that's only if I can get past the 'what is the registration?' question.... Thanks for the offer, very kind. I'll think about it - I just can't believe it is fuel - changing the leads has smoothed the running a lot - so it feels like it is electrical. Phil Waters Link to comment Share on other sites More sharing options...
Big Brother Posted June 30, 2006 Share Posted June 30, 2006 Phil, if Ford don't have CSP's instock - your welcome to try mine. Steve SE7EN-UP! The difference between ignorance and apathy? I don't know, and I couldn't care less! Link to comment Share on other sites More sharing options...
philwaters Posted July 1, 2006 Author Share Posted July 1, 2006 Thanks Steve - the one I tried didn't, but Bath road did, but I didn't have enough time to get to that one (I knew B&Q first was a mistake ) are you around this afternoon - I might brave the scorching temps if you don't mind me trying your collections of spares Phil Waters Link to comment Share on other sites More sharing options...
philwaters Posted July 3, 2006 Author Share Posted July 3, 2006 New CPs = no change. Revving the engine in the garage you can deffinitely hear that it is missing a lot more than just the odd time I see it on the shift lights and feel the loss of power. Lift the revs to 16-1700rpm and you can feel it through the linkage as a slight pulse. Certainly it is no where near as smooth at Steve Mott's at idle or as you lift the revs. Not sure ifI was right to do so, but I've always put this down to the lumpier cams I've got... I'm not so sure any more. I can't remember what Brent's was like on the same cams... Doh. If it wasn't for the shift lights indicating the spike in engine revs, I'd be wondering about mechanical stuff like cam timing, but the two just don't go together... Phil Waters Link to comment Share on other sites More sharing options...
Big Brother Posted July 3, 2006 Share Posted July 3, 2006 Not sure it helps but Brent was really impressed how smooth my idle was. He commented that it was smoother than his Zetec was. I guess some of your "lumpiness" may be due to the cams. Do you want to pop round one evening and we can swap the coilpacks? This will then rule out... Plugs CPS Coilpack EDIS Module Leads Supply to ECU, Coil etc (Voltage, current and interference) I guess that will leave you with either mapping and or ECU hardware problems *confused* Have you and Bill managed to get a scope on it yet? Steve SE7EN-UP! The difference between ignorance and apathy? I don't know, and I couldn't care less! Edited by - Se7en-Up! on 3 Jul 2006 23:24:57 Link to comment Share on other sites More sharing options...
philwaters Posted July 4, 2006 Author Share Posted July 4, 2006 Thanks for the offer Steve, I may take you up on that if I can't get hold of a cheap one from Blackbushe. As you say, everything else has been changed, so it can only be the coil or a ECU hardware thing - maybe a bad joint, but I looked over it all the other night and couldn't see anything.... Will hassle Bill to scope it if the coil doesn't fix anything - he has offered, but suggested the final change first, which is fair enough. Phil Waters Link to comment Share on other sites More sharing options...
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