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D3 - Fuel and Exhausts Everything to do with getting fuel into the engine, and fumes back out again

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  #11  
Old 11th April 2018, 03:58 PM
Architex_mA8tey's Avatar
Architex_mA8tey Architex_mA8tey is offline
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Has your LPG software ever been properly mapped to the car Lee? mine kept throwing up "too lean" faults until the LPG company had tweaked its software a couple of times and it gradually got better until it went and has never returned since - worth a look
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  #12  
Old 11th April 2018, 04:16 PM
ulfilias ulfilias is offline
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Architex_mA8tey - I've got the software myself. Alas the company that did the install (~10 months before i got the car) are in Poland which makes thing interesting in terms of having a word or popping over!

It's a pretty good kit from what i've read and quite well specified. I've re-routed the odd pipe and cable which I was less happy with but never found anything that was a show stopper. The LPG guy I took it too also checked it over but wasn't a Zenit

I've tried the adaptation routines and can get it to work, but the dropping cylinders makes it difficult etc
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Current :
2005 A8 Sport 4.2 V8 D3 - LPG not working still....

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1998 S8 PF 4.2 V8 D2 - Gearbox died ~120k
2002 S8 FL 4.2 40v V8 D2 Prins LPG - Engine valves met pistons ~230K

Also :
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  #13  
Old 11th April 2018, 04:26 PM
ainarssems ainarssems is offline
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Quote:
Originally Posted by ulfilias View Post
ainarssems - It's a D3!
I'll get my coat
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  #14  
Old 11th April 2018, 07:18 PM
ulfilias ulfilias is offline
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Quote:
Originally Posted by ainarssems View Post
I'll get my coat

Woooo, I've pulled!!!.....Oh wait!
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Current :
2005 A8 Sport 4.2 V8 D3 - LPG not working still....

Previous :
1998 S8 PF 4.2 V8 D2 - Gearbox died ~120k
2002 S8 FL 4.2 40v V8 D2 Prins LPG - Engine valves met pistons ~230K

Also :
1996 Jeep Grand Cherokee 4.0l (not worth selling!)
2003 Brabus Smart FourTwo (for sale)
2003 Mazda Rx8 2.3 (should sell)
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  #15  
Old 11th April 2018, 09:01 PM
Mechcanico Lee Mechcanico Lee is offline
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Post the 4 gas readings from the mot gas tester report
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  #16  
Old 12th April 2018, 09:28 PM
MatthewH MatthewH is offline
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The pre-cat O2 sensors on the BFM engine are 5-wire widebands if this is still relevant, I did mine last year. They were around £40 each (Bosch) shipped from USA, much cheaper than over here.

I think I had to remove the intake manifold. One side was fairly easy to swap but the other one was almost inaccessible. It took me a few days to finish the job in the end as I dropped my lambda socket somewhere behind the engine and couldn't find it. I think it's still in there now!
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  #17  
Old 13th April 2018, 02:37 PM
ulfilias ulfilias is offline
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Mechcanico Lee

Petrol - Fail
-----
Fast idle
Co 0.54% vs 0.3%
HC 208ppm vol vs 200ppm
L 1.056 vs 0.970 <> 1.030

2nd Fast idle
Co 0.84% vs 0.3%
HC 121ppm vol vs 200ppm
L 1.015 vs 0.970 <> 1.030

Natural idle
Co 0.53% vs 0.5%
-----

LPG - Pass
Co 0.55% vs 3.5%
HC 804ppm vol vs 1200ppm


MatthewH - Interesting. How and where ???
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Current :
2005 A8 Sport 4.2 V8 D3 - LPG not working still....

Previous :
1998 S8 PF 4.2 V8 D2 - Gearbox died ~120k
2002 S8 FL 4.2 40v V8 D2 Prins LPG - Engine valves met pistons ~230K

Also :
1996 Jeep Grand Cherokee 4.0l (not worth selling!)
2003 Brabus Smart FourTwo (for sale)
2003 Mazda Rx8 2.3 (should sell)
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  #18  
Old 13th April 2018, 06:31 PM
Mechcanico Lee Mechcanico Lee is offline
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On the first fast idle the lamda reading fails ....but itís failing only slightly and toward the lean side

On the second fast idle the lamda reading is a pass

Donít confuse the lamda gas reading with the lamda sensors .....itís often done

The lamda gas reading would be better off called mixture strength, lamda 1 or stoicimeteric 14.7 to 1 the ideal mixture strength .

If a car passes on the lamda reading this means the mixture strength is correct so any co and hc failings are because the cats are not doing there conversion .

Looks like the vcds readiness tests are bob on .

I have heard of this thinners thing in the fuel and if it works so be it , itís worth a go , donít buy cheap after market cats , they are rubbish with nowhere near the precious metals and rhodium of genuines .

If you are friendly with your Mot station often a good scragging up the road get the cats really hot then get it straight on the gas tester often gets the Co and hc down
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  #19  
Old 14th April 2018, 06:18 AM
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Adrian E Adrian E is offline
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+1 on aftermarket cats - the market is dominated by incredibly poor quality parts (I did some work investigating this in my previous job, with a view to instigating a change in legislation which hasn't yet happened)

I found a company in Germany that will refurbish your cats with metal substrate rather than ceramic and turn around time was pretty good. Germany has a higher level emissions test and their market isn't overly dominated by crap product - any product marked Blauer Engel (Blue Angel) meets that higher standard but supply of A8 aftermarket products is pretty limited and I've not checked what's out there for the D3.

Details are in this thread:

http://forum.a8parts.co.uk/showthrea...highlight=cats

I priced up OEM D2 cats and they were about £1k each, so a good saving if you assume that all cats will fail sooner rather than later.

Adrian
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  #20  
Old 17th April 2018, 10:12 AM
ulfilias ulfilias is offline
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The after market oddly don't seem to do anything for the D3 4.2 petrol that i've found. I know they are far less reliable anyway.

There's an argument of getting a decent cat for elsewhere and welding it into place!

However i'm currently looking at getting the LPG working properly as that's something more useful in the long term and something I should have done a while back. I've just tried swapping the MAF (bosch) and will give the LPG software another play.

Initially getting Cylinder 8 missfires though!

There's a thread here (different car)
https://www.pistonheads.com/gassing/...&f=23&t=866609

Which mentions different gappings for gas which may be something to look at

And another which also mentions about the HT spark leads may be an issue with arcing due to the higher specs
https://www.pistonheads.com/gassing/...&f=69&t=906093

Which also may be something to look at
__________________
Current :
2005 A8 Sport 4.2 V8 D3 - LPG not working still....

Previous :
1998 S8 PF 4.2 V8 D2 - Gearbox died ~120k
2002 S8 FL 4.2 40v V8 D2 Prins LPG - Engine valves met pistons ~230K

Also :
1996 Jeep Grand Cherokee 4.0l (not worth selling!)
2003 Brabus Smart FourTwo (for sale)
2003 Mazda Rx8 2.3 (should sell)
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