caterhamnut Posted January 12, 2006 Share Posted January 12, 2006 UPDATE - vibration has gone!! Last night we changed the fuel pump - it made a difference to the dull acceleration (I think!) but the vibration was still there - so we had a look under the car, and found that our propshaft was pretty worn, one of the universal joints was - to put it mildly - a little bit 'knocky' 😳 - brown 'dust' was clearly visible as the dry and worn joint ate itself! Luckily, Mark 355 had a 'spare' propshaft in the garage, which we fitted - vibration (unsurprisingly) gone!! It had been the first time I had been able to look under the car, due to loan of jack elswhere. Pleased its sorted, but also rather relieved that we have fixed a potentially dangerous component. Interestingly, I think we also had a number of other issues - the earths were a bit dodgy, the old HT leads were arcing and leaking, and I am pretty certain that the fuel pump was on the way out, as any throttle opening led to sluggish acceleration. Still - a cautionary tale about checking things like props - they don't go often, but check your nippples every now and again. Once again, huge thanks to all for their assistance - Peter C, Jason at Hellier and of course Mark!! We have been trying to trace the source of a 'vibration' on our car for the last week or so, with no success so far. Any ideas? Problem appeared about 3 weeks ago. It manifests itself in the form of a very even 'vibration' felt through your seat, under acceleration. It sounds/feels like a misfire, but the car does not stutter as much as a 'normal' misfire - the type of thing felt when a rev limiter cuts in, for example. It is much more even than that. However, the cars acceleration rate does suffer slightly when it happens. When driving, the 'vibration' seems to come in at about 3000rpm (and above) If you are accelerating reasonably gently the problem does not occur - it is only under load. Now, there is a chance that this could be mechanical - gearbox/diff/half shaft/prop shaft vibration? - but I would have thought that this type of problem would be felt more consistantly, even when free-wheeling for example, but it is not. I am pretty convinced it is fuel or electrical related, and as such have checked and replaced various things. So far - new HT leads, changed the plugs. Tried another coil, checked and replaced low tension plug on the coil (this can become very corroded) I have checked and re-fitted the main earths - battery to starter, engine to chassis. I have checked most connections - ECU plug, MFRU etc. I have also replaced the entire fuel rail (and therefore injectors) with a borrowed unit. I think that the problem has got a little better, but it is most certainly still there - any ideas about what else to try? Car is worn, dirty and corroded - due for rebuild any time soon, but we need it running now, up until it is booked in. Been folllowing Dave21's fuel pump issues - ours is working, or at least it makes a noise! Main thing is car runs pretty well until you accelerate quickly - that is when the problem occurs, so something is happening when things are under load. Looking for a brainwave!! www.mycaterham.com here 88,500 miles -1st 1.6k Supersport, '95 Motor Show car Edited by - angus&tessa on 19 Jan 2006 07:09:36 Link to comment Share on other sites More sharing options...
mav Posted January 12, 2006 Share Posted January 12, 2006 Perhaps a quick trip to your local MG/ rover service centre (here should at least be able to plug into the diagnostic port on the loom, and check if any sensors are failing? Link to comment Share on other sites More sharing options...
Myles Posted January 12, 2006 Share Posted January 12, 2006 Are you familiar with what 'knock' sounds like??? Tends to be an issue 'only' under load and it's the sort of thing you would hear and probably feel. When we first built the PSC engine, all kinds of things were horribly wrong (stab-in-the-air map for starters) and the car was seriously pinking/knocking. I managed a few miles under very ginger throttle, put if you tried to accelerate at more than cruise-ship pace, it all went horribly wrong. That was quite an extreme case - but if your pump/fuel filter/injectors/whatever are clogged/buggered, you could be experiencing the onset. FWIW, my first big job was to replace the propshaft - that manifested itself as a vibration over 80mph - and I would kind of expect that to be speed related (it's past the gears). On the face of it (and we all know how hard an email diagnosis is), I would put my 20p on something engine related. Project Scope-Creep is live... Alcester Racing 7's Equipe - 🙆🏻™ Alcester-Racing-Sevens.com Link to comment Share on other sites More sharing options...
caterhamnut Posted January 13, 2006 Author Share Posted January 13, 2006 Its a possibility Mav - I have a generally unfounded mis-trust of taking a car anywhere 'garage' like, but maybe in this case I should bite the bullet!! Myles - pretty sure it isn't a knocking/pinking issue - if it is then something has drasticaly changed, as it is a standard SS on standard ECU at the moment. I am certainly as convinced as I can be that it is engine related, as opposed to anything mechanical (in the engine or drive train) - I am gradually falling towards the fuel pump - had not thought of the filter - it isn't massively old, but might be worth checking (can you 'check' the filter?!) - fuel pump? Initial thought had been injectors, but replacing the whole fuel rail has made no significant difference (not a new replacement, but certainly not as old or high mileage as ours) 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 January 13, 2006 Author Share Posted January 13, 2006 One of the issues with getting it 'tested' is that the problem only occurs under load on the road - revving whilst stationary (in a garage?) everything sounds and feels fine - might be an issue with diagnostics, although I guess it might point to a dodgy sensor. Peter C has suggested (many things - thanks!) checking vacuum hoses... 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...
adrain Posted January 13, 2006 Share Posted January 13, 2006 Angus, I would not dismiss the fuel pump option yet. The intermittent symptom and more pronounced under load is classic and difficult to seperate from electrical/ignition and mechanical vibration thoughts. The fact that it is faulty/worn out does not necessarily show up on diagnostics either until it finally packs up! (My most recent simlar experience was with the V8 Discovery, admittedly where the fuel pump works very hard, and the intermittent problem went on for months.) I there any chance of swapping your pump for a known good'un and then thrashing the engine for a bit? Large viperblue/yellow 1.6 S/S Link to comment Share on other sites More sharing options...
Support Team Shaun_E Posted January 13, 2006 Support Team Share Posted January 13, 2006 Angus - there is a remote possibility it is the CRB. Those symptoms sound simlar to those I experienced just before I stripped my car down - the CRB was toast and in fact the clutch fork wasn't located properly either. The symptoms I got were a vibration that came in at certain revs and varied depending on the load. Wouldn't explain the loss of acceleration though unless the clutch was actually slipping. Yellow SL #32 Link to comment Share on other sites More sharing options...
Alex Wong1697456877 Posted January 13, 2006 Share Posted January 13, 2006 When my fuel pump failed (could see it going on my fuel pressure guage), I didn't get knock, but I got very lumpy acceleration. Alternators are also a common cause - bad connections etc. It's amazing how a bad alternator connection can make the ECU do all sorts of weird things. The K breaths into the throttle body I think - is there any chance of over filling with oil? Sorry - don't know much about metro engines.... Link to comment Share on other sites More sharing options...
caterhamnut Posted January 13, 2006 Author Share Posted January 13, 2006 Cheers guys - all useful suggestions and things I can check Anyone got a fuel pump lying around I can borrow 😬 🤔 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 January 13, 2006 Author Share Posted January 13, 2006 ...in fact, in case I need to get one - is it a caterham specific part, and if not, where is the best place to get one - rough cost? ...just in case! 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 January 18, 2006 Author Share Posted January 18, 2006 After a few more checks.....last thing to try now is the fuel pump - timing is fine, battery and alternator are working fine - any connection that we can find is fine. If not the fuel pump then I reckon it is a deeper 'loom' issue, which will be a b*gger to find...need to get that rebuild booked in asap!! Thanks to Mick for the offer of a fuel pump loan - hope to swap one in in the next few days and hope it solves the problem.... 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...
neil.cavanagh Posted January 18, 2006 Share Posted January 18, 2006 Angus, Do you have a cat in your exhaust? When the cats failed in my tintop recently it behaved pretty much just like your saying. Ie would rev ok when stationary, but under load above 2.5krpm the engine would 'smoothly' cut out. Engines are pretty dis-similar (small capacity high reving 4-pot compared to big capacity, low reviing v8) but the cat failing and blocking the exhaust, so giving increased back pressure might be having the same effect, albeit slightly milder. Oh, and I bet a CC cat wil be a damn site cheaper than the £1800 I had to cough up for the BMW ones!! Link to comment Share on other sites More sharing options...
caterhamnut Posted January 18, 2006 Author Share Posted January 18, 2006 Neil - cat-less! Though I understand the theory. We do have a cat system that appears once a year, for about a day 😳 😬 Link to comment Share on other sites More sharing options...
caterhamnut Posted January 19, 2006 Author Share Posted January 19, 2006 UPDATE - vibration has gone!! Last night we changed the fuel pump - it made a difference to the dull acceleration (I think!) but the vibration was still there - so we had a look under the car, and found that our propshaft was pretty worn, one of the universal joints was - to put it mildly - a little bit 'knocky' 😳 - brown 'dust' was clearly visible as the dry and worn joint ate itself! Luckily, Mark 355 had a 'spare' propshaft in the garage, which we fitted - vibration (unsurprisingly) gone!! It had been the first time I had been able to look under the car, due to loan of jack elswhere. Pleased its sorted, but also rather relieved that we have fixed a potentially dangerous component. Interestingly, I think we also had a number of other issues - the earths were a bit dodgy, the old HT leads were arcing and leaking, and I am pretty certain that the fuel pump was on the way out, as any throttle opening led to sluggish acceleration. Still - a cautionary tale about checking things like props - they don't go often, but check your nippples every now and again. Once again, huge thanks to all for their assistance - Peter C, Jason at Hellier and of course Mark!! 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...
shn7 Posted January 19, 2006 Share Posted January 19, 2006 Funnily enough I was under the car greasing my nipples last night *eek* having sorted a speedo problem. Steve. Link to comment Share on other sites More sharing options...
Normans_Ghost Posted January 19, 2006 Share Posted January 19, 2006 I was in bed sucking mine! Norman Verona, 1989 BDR 220bhp, Reg: B16BDR, Mem No 2166, the full story here You and your seven to The French Blatting Company Limited Link to comment Share on other sites More sharing options...
Alex Wong1697456877 Posted January 19, 2006 Share Posted January 19, 2006 I do worry alot about propshafts. Did you see Paul Gibb's after it failed? Glad you found your problem and always nice to fix ones you didn't know you had! Alex Link to comment Share on other sites More sharing options...
F355GTS Posted January 19, 2006 Share Posted January 19, 2006 As I understand with Paul Gibb's, both grease nipples were missing and the joints were totally dry, the level of movement in the UJ was shocking and I'm glad we found it when we did, I can't help feeling it would have let go very soon I'd recommend everybody checks theirs and gets their Nipples greased Mark Link to comment Share on other sites More sharing options...
caterhamnut Posted January 19, 2006 Author Share Posted January 19, 2006 Yep - saw Pauls 😳 - in fact that is why Mark replaced his a while back - just in case. Thats why he had a 'spare' one, which although 'used' is in pretty good condition ...all fixed and running much better - or at least it was until a petrol leak from the fuel rail caused by a crushed 'O' ring (my fault *mad* ) 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 January 19, 2006 Share Posted January 19, 2006 i did SAY that mine sounded identical and it was a prop shaft failure last year..... glad it's fixed now whur's me picture? Link to comment Share on other sites More sharing options...
LazerBrain Posted January 19, 2006 Share Posted January 19, 2006 Glad you got it sorted Angus btw, I'm still interested in having a quick ecu swap when you have some spare time. cheers, Darren. Link to comment Share on other sites More sharing options...
Kevsta Posted January 19, 2006 Share Posted January 19, 2006 Mine has a prop without grease nipples (95 chassis)!!! I am putting a new prop on this year though just to be on the safe side! Have seen two props fail on BECs...not pretty! Link to comment Share on other sites More sharing options...
caterhamnut Posted January 19, 2006 Author Share Posted January 19, 2006 Dave - you of all people know how these things work. It seems we had multiple issues. The HT leads were leaking. The earths were very dodgy. The fuel pump was almost certainly not at its best. Any one (or all) of these problems would have/did show the symptoms we had. The car would not accelerate. Access to a jack/lifting equipment was limited until last night. As soon as we could check the prop, we did, and fixed it. The other issues all needed attention as well. car now running even better, now all the issues have been sorted. Your drawing is in the same que it has always been in. Sorry for the delay, as I said, my priority so far this year has been the panic in trying to get myself some sort of wage at the end of the month. You will forgive me I am sure, if some of these things take priority - for the very short term - over your cartoon It is nothing personal, I have not forgotten, there are other people waiting awell, and I am sorry. And yes - it has been a really really sh*t day so far..... 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 January 19, 2006 Share Posted January 19, 2006 you don't fancy some random contract work as an onsite manager for me between times then? and i'm only joshing about the artwork... and the propshaft. 😬 Link to comment Share on other sites More sharing options...
caterhamnut Posted January 19, 2006 Author Share Posted January 19, 2006 😬 - got back last night from marks - started work at about 11.30pm - lots. Got up really early - set off to drive from Egham to Oxford to finish work just before presentation. handbrake for ride-on tractors. Got as far as Maidenhead. Strong petrol smell - 'umm - must be at the back where we replaced fuel pump....' - no - trapped O ring in fuel rail is now allowing fuel to pour/drip out. Do really stupid thing and turn round, drive back home - try and finish work, email for presentation. Trying to fix car inbetween scans. Finally sort it - set off for Oxford lunchtime. Here now - loads to do - probably miss Jez talk at Wotton Hatch Surrey meet....... managerial role - no ta - I'm more of a 'doer' - creating things, not f*cking up the creating process like most of the 'managers' I have come into contact with. 😳 😬 😬 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...
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