Archived Message
RV8 exhaust emission values not OK
A friend of mine has problems with the exhaust/cat emission values and so I took a quick look underneath on my hands and knees. The cats. are still there!! and apparently, according to my friend, rattle and so I assume the inside ceramic baffles have gone/broken up. My question is whether this has happened previously or should we be looking elswhere such as the cat. sensors. His RV8 is a 1995 model and so I'm a little unsure whether the cats. could have failed and also the cause, of course.
Peter Garton
05/07/2012 @  12:35
Under topic: RV8
Archived Reply(ies) received for this Message
RV8 exhaust emission values not OK
Peter, there have been several reports of the protective shields surrounding the cats rattling and then falling off as they are only held on with tack welds. This happened to me last year. They can either be rewelded on properly or the whole exhaust section which includes the cat will need replacing.
Ian Quarrington
06/07/2012 @  01:15
RV8 exhaust emission values not OK
Thank you Ian, but as you can see from my thread his problem is the emission values. I have arranged that he gets along to Bosch who will test the sensors etc., to see whether they are functioning or whether the cats. themselves are defective.
Peter Garton
06/07/2012 @  15:47
RV8 exhaust emission values not OK
Hi Peter
What do you mean by "exhaust/cat emission values "? If you mean the sensors that are attached to the side of the cats then how do you know there is a problem ? If this is a Japanese delivered RV8 and the "cat overheat warning light" is on whenever the ignition is on then I can save your friend a lot of time and money. This is a false warning that is due to an electrical fault in the wiring system for most Japanese RV8s.

The easy fix is remove the warning globe.The expensive fix is to pay someone to pull apart the electrical system to find the "manufactured" fault.
If you are afraid of the cat being faulty ? Then I have been told that the cat would have to be almost 1000 degrees before the warning light should come on. This situation would be very obvious if it was occuring on your friends RV8.
Peter Varley
06/07/2012 @  16:55
RV8 exhaust emission values not OK
Thank you,Peter .No the warnong light is not coming on apparently. Either he or someone reckons that there is something loose inside the cats (not the shields Ian) so I supposed that the ceramic baffles have broken. I assume he found out about his problem when the car failed the T‹V exhaust emission test. i.e. when they stick that probe up the tail pipe and note the computer results.
Peter Garton
06/07/2012 @  18:17
RV8 exhaust emission values not OK
Hi Peter!

In theory, a well tuned closed loop EFI system could very well pass an emissions test with no cats at all. So it's well worth checking for sensor faults.

If it is a HC (unburnt fuel) failure a common failure on the 14CUX as I understand it is the coolant temp sensor which will cause rich running and high HC values.

Bad lambda sensors or air flow meter could cause rich running as well.

Best regards,
Erik Persson
07/07/2012 @  06:44
RV8 exhaust emission values not OK
Yes, Erik, that was my suspicion too! Anyway I'm sure Bosch will come up with the answer. What puzzles me is if the ceramic baffles have broken, how can this occur? Of course backfiring and the like are obvious answers but I heard the engine and it was perfect starting up well, accelerating well and ticking over nicely.
Peter Garton
07/07/2012 @  14:20
RV8 exhaust emission values not OK
The Lucas Efi is very simple so your friends at Bosch should find any faults. Theyíll probably start by checking the Lambda sensors Ė but donít discount the ignition, if the car has been running with a misfire the cats could be damaged. The engine will start and idle on 7 cylinders and will still sound and run reasonably well.
Check the simple things like spark plugs and leads and if the plugs havenít been changed in a while a new set would be a good idea. Make sure the plug leads are decent quality and in good condition but high performance leads like Magnecor are certainly not necessary, the ignition system simply doesnít have enough energy to require them.
Has the car been used a lot a slow speeds, short journeys and/or cold running?
Of course the cats donít last forever, are they the originals?
Geoff King
07/07/2012 @  21:01
RV8 exhaust emission values not OK
Thank you for your advice, Geoff. The leads are all ojk and have been renewed to Magnecor. The engine is running sweetly on all 8 cylinders but will have this check as you advise. We'll get the plugs checked and exchanged if necessary. As mentioned I suspected the sensors, initially, as a first step. The car has been run normally and Christoph has used the speed and power to the full!
Will report when I have more substantiated information to pass on, but will be in the Highlands this coming week although the weather forecast looks frightening. I'm not attempting to come over in the RV8 becasue we want to do quite a bit of shopping and stocking up on lamb, cheddar,bacon and stilton etc., etc.!!
Peter Garton
08/07/2012 @  14:14
RV8 exhaust emission values not OK
And Whisky too I hope Peter. I must say I donít miss the weather now being some 1800km south of but itís a pity you are not taking the RV8, there are some wonderful roads to enjoy with the sound of the V8 echoing off the mountains. Iíd leave the spare wheel at home and use the space to pack your provisions Ė actually I donít even have a spare wheel.

I donít know how well you know the area but if you are heading up the east side of Scotland the B974 off of the main road to Aberdeen is one of the best roads you will find and ends in Banchory where we used to live. Then head west along the Dee valley before going north up the A939 to the Highlands Ė you wonít be disappointed.
Geoff King
08/07/2012 @  16:51
RV8 exhaust emission values not OK
The Bosch guys should probably be able to find the fault by elimination but the 14CUX is not completely brain dead and features a diagnostic port which can actually tell if there is a malfunctioning lambda sensor or MAF.

Taking it to a LR dealer with the proper code reader could give some very good hints at least.

Another thing that might complicate things slightly if taking it to a generic car electrician: The oxygen sensors on the 14CUX are not standard Zirconuim but of a type using titanium only used by (Land)Rover V8's and a handful other engines of other makes.
Erik Persson
09/07/2012 @  08:07
RV8 exhaust emission values not OK
Many thanks, Erik! Christoph is now awaiting the single silencer exhaust system from Clive plus the Spax upgrade shocks and will get it all done in one go, apparently. I'm quite confident my Bosch guy will sort it all out satisfactorily but will report back to this thread in the next 10-14 days or so.
Peter Garton
09/07/2012 @  14:22
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