Brucey Posted April 10, 2006 Share Posted April 10, 2006 Further to my previous thread, my 7 is still in the garage trying to pass it's emissions for the MOT . Basically it's failing CO level on Natural Idle Test. 3.9% at 1018 rpm (0.50 max allowed) The guy has checked Lambada output (o.k), cam timing (near enough!), compression & leakdown tests (ok), air leaks around inlet manifold (none found). He stuck a vacuum generator on the pipe going to the ecu and managed to reduce the CO, but the car wouldn't run! I've known the guy doing the work for a number of years (into classic bikes) and he is VERY good at diagnosing faults but this is beginning to stump him! I've given him Caterham's & Minster's phone numbers, but has anyone else had a similar problem? Checking the emissions done last year (previous owner) it passed but engine speed is noted as 'not checked' Bruce. Edited by - brucey on 12 Apr 2006 23:57:00 Link to comment Share on other sites More sharing options...
CageyH Posted April 10, 2006 Share Posted April 10, 2006 Sounds like it is time for a programmable ECU if all else fails. Then you can have an MOT friendly MAP loaded. Either that or try a different garage! Link to comment Share on other sites More sharing options...
Dicky Posted April 10, 2006 Share Posted April 10, 2006 As already suggested time to find a new garage me thinks ! Link to comment Share on other sites More sharing options...
Brucey Posted April 10, 2006 Author Share Posted April 10, 2006 Thanks for your suggestions Cagey & Dicky. It just bugs me why the problem is so obscure. Surely a bog standard super sport should have no problems on emissions? To imply changing the ECU to a mappable one would help must mean something has changed on the existing ECU input/output. If the cat had gone I would have thought it would fail on both 'Normal Idle' & 'Fast Idle'. The guy trying to sort it keeps a record of all the cars that have failed, what engine and what was done to resolve it. His selection of about 8 Rovers that failed on CO usually points to Lambada Sensor or leaking/distorted throttle body (plastic type). My car has an alloy throttle body with no obvious air leaks and the Lambada sensor checks out o.k on his tester. Even though the Injector timing was checked, he did wonder if it was getting 2 squirts instead of 1 thus making it run rich at tick over. Is this possible? I guess chucking injector cleaner in and giving it a good blat won't help! I suppose I'll have to cut my losses and try and find 'another' garage. As the MOT has now run out, I'll have to plan my blats around MOT tests but it could get expensive! Unfortunately things like this 'niggle' me (and I know the mechanic is the same) until the answer is identified. Bruce. Link to comment Share on other sites More sharing options...
Nick Pargiter Posted April 11, 2006 Share Posted April 11, 2006 Bruce Given the age of your car they, I think they should only be looking for 'Visible Emissions'. I have a 94 1.4ss and thats all they did on mine. I cannot remember the name of the garage but they were Banstead/Coulsdon way. Nick Link to comment Share on other sites More sharing options...
martinwhitcher Posted April 11, 2006 Share Posted April 11, 2006 agree with Nick, surley a visable test only as pre 97? Martin MW 51 CAT Superlight No.171 now known as:Superlight DVA 207 Link to comment Share on other sites More sharing options...
Brucey Posted April 11, 2006 Author Share Posted April 11, 2006 Nick & Martin, thanks for your comments. My car seems to be one of the few cars that were factory built in 1993. The 6th digit of the VIN is 'F' and it is fitted with the original cat (internal) exhaust system. All this means that the VOSA site chucks out 'standard cat test' when the details are put in. I suppose the garage could try selecting 'another' model as this part of the MOT process for a Caterham is very vaugue. I really just wanted to know if the garage has tried everything or has anyone else managed to resolve a similar problem (without replacing the ECU). Bruce. Link to comment Share on other sites More sharing options...
Peter Carmichael Posted April 11, 2006 Share Posted April 11, 2006 surely a visible test only as pre 97? Only if you're as good at reading the instructions as the tester that Myles uses. It is all quite clear. Factory cars are no different from any other car you might have bought. Post-August '92 and fitted with original equipment catalysts, as verified by the chassis number, then they should be put through a Cat test. I reckon the hint in your symptoms is that the Lambda is spot on, but the CO is as high as it would be without a catalyst fitted - in fact it is a fail on the non-catalyst test, with CO required to be less than 3.5%. Either your cat is not working (contaminated/broken up) or it is not up to temperature. Note that the test criteria require a minimum oil temperature at test time of 75degC. This is where a good thrash of everything is required. Failing that you might have to borrow/acquire another exhaust can to prove that the cat in your exhaust is at fault. Link to comment Share on other sites More sharing options...
Brucey Posted April 11, 2006 Author Share Posted April 11, 2006 Peter, thanks for your comments. Unfortunately trying another cat may be a little difficult as my car is fitted with a 'unique' (read PITA) internal sytem. The fact that it passed with a CO of 0.05% at 2841 rpm makes me think the cat was o.k. The garage seem to think the symptoms are consistant with running too rich at slow idle. Bruce. Link to comment Share on other sites More sharing options...
Horizontal Posted April 11, 2006 Share Posted April 11, 2006 Probably of no use, but my old (then new) superlight fail on emmissions at the SVA stage, It was a fuel pressure problem, tweeked by Dartford and all was well. Sylvia Silverstone on 45's Link to comment Share on other sites More sharing options...
Brucey Posted April 11, 2006 Author Share Posted April 11, 2006 Horizontal, Thanks for that. Another one for the garage to check! Bruce. Link to comment Share on other sites More sharing options...
Peter Carmichael Posted April 11, 2006 Share Posted April 11, 2006 My car has an alloy throttle body with no obvious air leaks Yet you have an idle speed over 1000rpm. Shurely shome mishtake Still not convinced you've got it hot enough for the cat to be working at idle... especially as this is what catches pretty much everyone else out. Link to comment Share on other sites More sharing options...
CageyH Posted April 11, 2006 Share Posted April 11, 2006 Is the IACV functioning correctly? Link to comment Share on other sites More sharing options...
Allen Payne Posted April 11, 2006 Share Posted April 11, 2006 These don't have an IACV but a stepper motor that act directly on the throttle butterfly. It might be worth disconnecting the stepper motor and seeing what idle speed the engine runs at without it Would re-setting the ECU help? Link to comment Share on other sites More sharing options...
Brucey Posted April 11, 2006 Author Share Posted April 11, 2006 Peter, Thanks again for the input. The guy trying to sort it spoke to Caterham Cars today and they suggested chucking a load of injector cleaner etc in it and taking it for a good thrash! I wonder how many volenteers they will have for that then! Cagey & Alan, Car does have a stepper motor. I think it has already been tried disconnected as the mechanic had the air cleaner off to make sure the butterfly was closing correctly. If I get it through, I think I'll change to a second hand cat side exhaust in the near future. At least it would be easier to eliminate as a potential problem next time (unfortunately the living room carpet took priority over the powerspeed bulk buy ☹️) Bruce. Link to comment Share on other sites More sharing options...
Brucey Posted April 12, 2006 Author Share Posted April 12, 2006 To anyone out there who is still interested (can't be many left now!) Garage is putting fuel injector cleaner in today and flushing oil (incase problem is 'sticky' tappets). Will then give it a good run and re test idle emissions. I'm a little concerned about mixing the flushing oil with my year old foam sump baffle and will probably have to replace the semi synthetic oil and filter again sooner rather than later. I spoke to CC regarding this, but they couldn't advise on the effect of flushing oil on their baffle. George in the CC tech dept did however say recheck Lambada sensor & water temp sensor. Unfortunately the vacuum sensor is part of the ECU and needs special kit to check. Get the feeling it's time to take the car back and 'have a good think' as to what I should do next. Maybe I can get an MOT on the condition I don't start the engine! Bruce. Link to comment Share on other sites More sharing options...
Brucey Posted April 12, 2006 Author Share Posted April 12, 2006 Went for my (now regular) trip to the garage who are doing the MOT work on my Caterham and the guy handed me a nice new MOT certificate I haven't got the bill yet though ☹️. Any way, they flushed & changed the oil (probably unnecessary) and chucked about a pint of injector cleaner in the tank. After a blat down the road, it went straight in for an emissions retest and passed. The downside is I will have spent a lot of money (charging 4 hour labour + parts) for somthing I could have easily done myself. The upside is that I know a lot more about the condidtion of my engine (cam timing, compression & leak tests, sensors etc) and I can drive it again ❗ Many thanks to everyone who contributed for your input, advice and general encouragement. I think Peter probably got nearest to the solution and I know what I'll be doing before taking it for another MOT next year 😬 Now where did I put those verniers? Bruce. Link to comment Share on other sites More sharing options...
Bob Corb Posted April 12, 2006 Share Posted April 12, 2006 Fantastic news. I've been putting injector cleaner in my diesel beemer for the last few weeks to improve a dicky idle problem, it does have a significant effect. I never thought to suggest it here though Link to comment Share on other sites More sharing options...
shn7 Posted April 13, 2006 Share Posted April 13, 2006 😬 The sun has got his hat on and Brucey's coming out to play.... 😬 Steve. Link to comment Share on other sites More sharing options...
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