caterhamnut Posted December 19, 2005 Share Posted December 19, 2005 Our car has been suffering from a quite serious fault, which has been getting worse and worse. Started off as a slight 'bumpiness' in the running - not enough to call 'rough' and not as defined as a 'missfire'. Anyway, last week it became so regular that it actually felt like a vibration - a regular 'bumping' that could be felt through the seat. Car seemed to run 'ok'. It got so strong we actually changed our diagnosis and thought it was something mechanical - a loose prop shaft, a diff on its way out - half shaft buggered etc etc. More apparent under load - pop the clutch in and the engine sounded fine, vibration stopped - so we figured something in the power train that was only apparent under load. However, on this particular journey, the car started to miss a bit. You could crack the throttle open and you would ge all the noise, nothing happened then the car suddently picked up. This seemed to confirm that it was in fact electrical related, or possibly fuel. So - HT leads are number one concern, or coil breaking down. This would tie in with the fact that the problem happens when the car is under load (particularly 5th gear pulling) Looking at the engine tonight in the pitch black, and there is visible tracking on the HT leads over the can cover. Is this tracking enough to cause such an 'even' missing under load, and is it simply a case of replacing the HT leads, or can the 'magic blue sparky stuff' track from elswhere along the HT leads? Anything else to check? www.mycaterham.com here 88,500 miles -1st 1.6k Supersport, '95 Motor Show car Link to comment Share on other sites More sharing options...
mav Posted December 19, 2005 Share Posted December 19, 2005 From your desription, it soulds like your ht leads are bugg3red Link to comment Share on other sites More sharing options...
caterhamnut Posted December 19, 2005 Author Share Posted December 19, 2005 yep 😬 - thats what I reckon - just wondering if this tracking would cause such 'violent' vibration etc - obviously it seems I need to replace them regardless..... www.mycaterham.com here 88,500 miles -1st 1.6k Supersport, '95 Motor Show car Link to comment Share on other sites More sharing options...
Mark Durrant Posted December 19, 2005 Share Posted December 19, 2005 Angus I have a spare set of leads you can have that were OK when I removed them from my car Mark D Su77on Se7ens Link to comment Share on other sites More sharing options...
caterhamnut Posted December 19, 2005 Author Share Posted December 19, 2005 Hi Mark - thanks for the offer - I'll drop you an email. One of the issues is that the cables we currently have are also '2nd hand' (like most of our car!!) so not sure how old, how likely to be b*ggered etc etc. Just wondering if it is time to invest in better quality leads (Magnitron?) rather than go for the Halfords option. If we forget the whole 'improve performance' arguement, are more expensive HT leads from people like Magnitron likely to last longer before breaking down? www.mycaterham.com here 88,500 miles -1st 1.6k Supersport, '95 Motor Show car Link to comment Share on other sites More sharing options...
henry21p Posted December 19, 2005 Share Posted December 19, 2005 When I last experienced something almost identical to what you are describing, it was combination of my front UJ and a knackered front wheel bearing (other than your diagnosis re throttle). the "throbbing" or "thumming" noise has also been known when I've had a spark plug caking up for some unknown reason. I suppose if you look at them and on is clearly a different colour from the rest, that might do it. Edited by - Dave21P on 19 Dec 2005 11:06:29 Link to comment Share on other sites More sharing options...
caterhamnut Posted December 19, 2005 Author Share Posted December 19, 2005 Yep, thanks Dave - will check the spark plugs to see if it is an injector issue. I guess it could still be a mechanical issue. Just feels like it is linked to engine/missing/performance/roughish running. HT lead or coil problem would be exasperated under load, which is when this vibration occurs..... www.mycaterham.com here 88,500 miles -1st 1.6k Supersport, '95 Motor Show car Link to comment Share on other sites More sharing options...
Allen Payne Posted December 19, 2005 Share Posted December 19, 2005 When my car got jerky under acceleration it was beacuse the vacuum hose going to the MEMS unit was full of oil! Link to comment Share on other sites More sharing options...
caterhamnut Posted December 19, 2005 Author Share Posted December 19, 2005 Never heard of that one Allen - another good thing to check though. Certainly BOSS had a jerky issue in the summer - on close inspection of the problem we saw that he had trapped the vacuum hose slightly and was pinching it, when he had remounted the ECU after removal. www.mycaterham.com here 88,500 miles -1st 1.6k Supersport, '95 Motor Show car Link to comment Share on other sites More sharing options...
Mark Durrant Posted December 19, 2005 Share Posted December 19, 2005 Angus YHM Mark D Su77on Se7ens Link to comment Share on other sites More sharing options...
Support Team Shaun_E Posted December 19, 2005 Support Team Share Posted December 19, 2005 Angus - ask Santa for a set of Magnecor leads. I got mine from Eliseparts. Not cheap but very good quality - ask Michael about the excellent service he had from Magnecor when he broke one of his leads. I have the red ones but the blues are a bit cheaper and would be a good choice still. If you need a short term solution I think I still have my original leads in the garage somewhere. Yellow SL #32 Edited by - Shaun_E on 19 Dec 2005 11:53:17 Link to comment Share on other sites More sharing options...
caterhamnut Posted December 19, 2005 Author Share Posted December 19, 2005 cheers all - magnecor - thats who I was think of when I talked about magnetron!!I think I will invest in these sometime - my Halfords ones only seem to last a year!! www.mycaterham.com here 88,500 miles -1st 1.6k Supersport, '95 Motor Show car Link to comment Share on other sites More sharing options...
caterhamnut Posted December 19, 2005 Author Share Posted December 19, 2005 Mark - I'll drop you a line later - no rush mate, cheers www.mycaterham.com here 88,500 miles -1st 1.6k Supersport, '95 Motor Show car Link to comment Share on other sites More sharing options...
caterhamnut Posted December 19, 2005 Author Share Posted December 19, 2005 Thanks for all the offers of spare leads - what stars. I have decided to just bite the bullet and get some magnecors - I was going to anyway at some point, so may as well do it now. I seem to have this tracking issue every winter, so to save false economy on the Halfords ones, I'll spend some more instead. Thanks for the links Shaun... ...big *thumbup* for Eliseparts.com - emailed and placed and order, made a note of the urgency, they called me back within about 10 minutes, and I'll get them tomorrow Not sure if this issue is the fundimental problem, but it will at least eliminate the leads from the equation, and mine are certainly tracking anyway, so..... www.mycaterham.com here 88,500 miles -1st 1.6k Supersport, '95 Motor Show car Link to comment Share on other sites More sharing options...
henry21p Posted December 19, 2005 Share Posted December 19, 2005 here's a thought for you. poor temperature compensation on the car's fuelling/ignition map set up by a faulty sender somewhere? Link to comment Share on other sites More sharing options...
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