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| Lorryman100 Member Since: 01 Oct 2010 Location: Here Posts: 2686  |
Mick, it sounds like a fuelling issue with the fuel rail with the anti stall mixing up the symptoms. When the engine is cold the EMS uses a warm up cycle to get the engine up to operating temp just like a choke did on petrol engines. I know it does this as I have numerous live data files which show slightly higher rail pressures until the engine is warm on a standard OEM fuel file. The clattery engine sound is indicative of high rail pressure when under acceleration and LR had a bulletin out to rectify this issue, but only when P1169 and the MIL appeared. The fix was a new fuel rail and this happened to me about a year ago. The only way to really tell would be to plug it into a diagnostic tool and see what the engine sensors were reporting at the time.
 Click image to enlarge If you think it is the EGR valve as you first suspected simply unplug it the next time you do exactly the same journey and see if that makes a difference to the anti stall when using the engine as a brake. When you climb the hill do you have the throttle pedal to the floor? If so then the EGR valve will be fully closed so the test will work on the uphill climb without affecting the results, as the unplugged EGR will have the same effect, the valve will be closed. You will get a couple of tested DTC's logged and the MIL, also the Puma may enter limp mode. If it does just switch off and restart to clear it. Click image to enlarge HTH Brian |
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30th Dec 2011 9:53pm |
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| mick Member Since: 08 Feb 2010 Location: Yorkshire Posts: 2109  
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Cheers Brian your idea sounds about right will have to call at dealers
Thanks  |
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30th Dec 2011 10:44pm |
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| mick Member Since: 08 Feb 2010 Location: Yorkshire Posts: 2109
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Finally got to the dealers today recently the Egr started making strange noises
 But the engine ran better than it ever has smooth no surging good fuel consumption.
Anyway they ordered me a new Egr and fitted it today so will see how it goes Strange though no faults were shown on computer. |
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14th Feb 2012 8:42pm |
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| Lorryman100 Member Since: 01 Oct 2010 Location: Here Posts: 2686 |
Mick, it sounds as if the EGR was sticking open when cold and then sticking closed when warm which is what gave you the smooth running and good fuel consumption. The extra clatter you heard was probably the ECU compensating for the open EGR valve by increasing the rail pressure and allowing more fuel into the burn, though I would have expected to see a MIL light and a DTC logged if this was the case? When you get a chance unplug the EGR electrical connection and see if you get the same smooth power as before when the EGR was faulty? Closing the EGR really does make a big difference to the drive ability of the standard fuel map. If the MIL annoys you then you can always plug it back in or get an EGR closed upgrade on the OEM fuel file to keep it closed permanently by the software. Have a look at this post I did on the EGR closed OEM fuel file upgrade I did on a couple of Alive tuning files.
http://www.defender2.net/forum/topic10564.html |
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15th Feb 2012 2:35pm |
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| Caterham Member Since: 06 Nov 2008 Location: Birmingham Posts: 6298 
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lorryman100
you mentioned a new fuel rail......do you mean just a fuel rail sensor? and if so can these be easily replaced ie by a mupper like myself......and if so any idea how much they are? be interesting to see if symptoms have gone after new egr ?? |
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15th Feb 2012 5:13pm |
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| Lorryman100 Member Since: 01 Oct 2010 Location: Here Posts: 2686 |
QO68 is a service action plan and the dealers would have carried out this notice after hearing Mick's symptoms. The new EGR would have been tested and any software updates should have been done at the same time, so the original conditions experienced with the old failing EGR will not be the same now with the new one fitted. As to the fuel rail sensor, this is not a serviceable part as it is fixed onto the end of the fuel rail. If that sensor fails then a new fuel rail is required, only the pressure limiting valve is replaceable. |
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15th Feb 2012 6:21pm |
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| Caterham Member Since: 06 Nov 2008 Location: Birmingham Posts: 6298
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not wanting to take things over here but my problem (assuming its not in my head) could be the same as micks or similar.
I get the clattery engine sound but its 50 / 50. might have a whole journey when its like this, othertimes its just parts of a journey. I've had the car over 12 months and its always been the same. when its clattery it really doesn't like to pick up, engine unresponsive making gear changes difficult because its difficult to get the engine speed. othertimes the engine picks up lovely and I have no calms giving it plenty of revs (3k or more is plenty to me). been to dealers and not fault codes...I've tried disconnecting the egr once but only for a short period and no obvious difference? any thoughts / pointers would be much appreciated. |
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16th Feb 2012 7:23am |
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| Lorryman100 Member Since: 01 Oct 2010 Location: Here Posts: 2686 |
@Caterham, what is the age and mileage of your Puma? Do you have a remap? What fuel supplier do you use? Do you use 2SO? Is the clattery sound worse or the same after a cold start? Does the glowplug cycle remain constant? Does the EGR complete it's test cycle on shut down? Do you know the software version on your Puma? Can you explain the noise that has you concerned? If you have a scangauge? What is the fuel rail pressure when you hear the clatter?
Sorry for all the questions but the more info you can supply the better the chances are one of us can aid you.
Brian. |
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16th Feb 2012 11:12pm |
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| Caterham Member Since: 06 Nov 2008 Location: Birmingham Posts: 6298
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I don't mind the questions one little bit....I just want to resolve the issue I have
my puma is a Nov 2010 (one of the early N1 class models - although mechanically I don't think they changed it) so I understand it has the later generation egr which I believe does alway do its cycle when you switch the engine off. the car has done 17k miles but has been like this since new. when I drove the car off the forcourt it kangarooed within a few hundred yards and only did that once more......c4 months later the ecu throw a tantrum and had to be replaced. fuel varies but I now tend to avoid supermarkets and usually use Esso or BP. the clattery sound can be worse when warm to the point where the engine can actually sound alot smoother when cold but unfortunately this can vary (I've often thought when its cold and perhaps having a rich mix its smoother and then when warm its under fueled - not sure tho). the glow plug cycle seems to vary as I would expect it to with warm engine / weather being short and long on a cold morning. unfortunately I don't know what software it is running but believe it had the latest installed Nov 11. No scangauge so no idea of fuel pressures. the noise is simply a clattery sound similar but amplified to that of a petrol car pinking underload. when this happends and it can be for a whole journey not just a few seconds the engine doesn't want to pick up speed quickly ie its very unresponsive so difficult to get engine speed right for smooth gear change. there's no performance ie there's a hill near me where I can happily pootle up it in top at about 40. not chance when the noise is there. 
I did try 2so and thought that had solved it but I don't think so. using redex at the moment? I'll drop back onto the 2so next fill up see if its any different. |
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17th Feb 2012 8:01am |
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| The Boy Member Since: 28 Aug 2008 Location: East Northants Posts: 1459  
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Mine does the “pinking thing also” pretty sure I remember my last one doing it also. I bugs the hell out of me!!!! But for me it seems worse when cold. I have just started using 2 stroke and this does seem to help but it maybe it is because of the milder weather.
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17th Feb 2012 8:12am |
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| Caterham Member Since: 06 Nov 2008 Location: Birmingham Posts: 6298
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the boy.....doesn't it do it all the time.
the garage have looked at mine and said its all ok. but how the hell can it come and go. when it goes away the engine is sweet as a nut and the unusual induction noise is a pleasure to listen to...surely it should be like this all the time? |
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17th Feb 2012 8:17am |
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| Lorryman100 Member Since: 01 Oct 2010 Location: Here Posts: 2686 |
You could try raising the cetane level by filling with BP Ultimate diesel and adding a can of Forte diesel treatment. This combination of the higher cetane mix and cleaning additives will first smooth out the fuel burn, high cetane levels in the fuel ignite quicker and burn smoother reducing emission/carbon deposits and the Forte is a dedicated cleaning agent. By doing this first you are effectively cleaning the engines fuel system and then giving yourself a starting point to start diagnosing the symptoms if they are still present after cleaning.
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17th Feb 2012 12:16pm |
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| Caterham Member Since: 06 Nov 2008 Location: Birmingham Posts: 6298
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will try and let you know - thank you lorryman100
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17th Feb 2012 9:11pm |
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