A8 Parts Forum  

Go Back   A8 Parts Forum > A8 D3 > D3 - Engine Bay

D3 - Engine Bay Everything under the bonnet

Reply
 
Thread Tools Display Modes
  #21  
Old 4th April 2022, 03:37 PM
JG27 JG27 is offline
Junior Member
 
Join Date: Mar 2022
Posts: 3
Default

Quote:
Originally Posted by 1781cc View Post
MRC are a company based in Banbury, well known for their Audi/VW tuning experience. If you are local they are worth dropping a line, if not, there are similar companies that may help and probably some local to you.
I'm having the same issue with my 2.7T - could you please help what do you meant by "inlet flap"?
Reply With Quote
  #22  
Old 16th April 2022, 01:56 PM
JG27 JG27 is offline
Junior Member
 
Join Date: Mar 2022
Posts: 3
Default

Quote:
Originally Posted by 1781cc View Post
I had this on my B6 S4, cylinder 3 at the time, kept rotating coil packs, no solution - turned out to be the inlet flap - mrc sorted that and the lpg was fine, it was a BRC system
what do you mean by inlet flap? i have the same problem
Reply With Quote
  #23  
Old 16th April 2022, 03:17 PM
steamship's Avatar
steamship steamship is offline
Senior Member
 
Join Date: Jun 2013
Location: Londonderry, Northern Ireland
Posts: 2,431
Default

Quote:
Originally Posted by JG27 View Post
what do you mean by inlet flap? i have the same problem
He may be referring to the flaps in the intake manifold.
__________________
2001 A8 D2 FL 3.7 Q - LPG Conversion, Engine: AKC, Gearbox:FBB, Colour:LY5X Aqua Blue pearl effect, Interior:WJ light beige/dark beige valcona leather with burr walnut inserts

My DIY jobs - Replaced alarm horn, Replaced Coolant Temp sensor, Updated RNS-D firmware, Installed Reversing Camera and Digital TV, Dashcam Installation, Retrofitted Rear Blinds, Auto-Dimming Rear View Mirror, Chrome Boot Struts

Sold! 2008 S8 D3 5.2 V10 - Engine: BSM, Gearbox:KLW, Colour:LY7F Suzuka Grey Pearl Effect, Interior:Black/Black with Silver/Black valcona leather with carbon atlas inserts, Bang & Olufsen, Heated windscreen, Soft-close doors, TV, DAB, AMI, Quad Zone, Auto Boot, Auto dim Mirrors, Keyless entry, PDC with rearview camera, AFS II Headlights

My DIY jobs - Fan Jet Windscreen Washers, Retrofitted Electric Side Blinds
Reply With Quote
  #24  
Old 17th April 2022, 09:18 AM
JG27 JG27 is offline
Junior Member
 
Join Date: Mar 2022
Posts: 3
Default

Hmm ok, my 2.7T petrol engine does not have such flaps. Having missfire on cylinder 3, got spark, new coil, compression is good, on low rpm it just disconnects (maybe shut off fuel). New wires to coil and fuel injector.
Reply With Quote
  #25  
Old 17th April 2022, 11:49 AM
steamship's Avatar
steamship steamship is offline
Senior Member
 
Join Date: Jun 2013
Location: Londonderry, Northern Ireland
Posts: 2,431
Default

Quote:
Originally Posted by JG27 View Post
Hmm ok, my 2.7T petrol engine does not have such flaps. Having missfire on cylinder 3, got spark, new coil, compression is good, on low rpm it just disconnects (maybe shut off fuel). New wires to coil and fuel injector.
Just noticed the '2.7T'. A8s were never fitted with a 2.7T engine. A better alternative would be one of the various other Audi forums that cover ALL Audi models. Here are four such examples, all of which have sub-forums dedicated to the 2.7T engine. However, prior to checking those out, you should perhaps watch the following video where he describes (and identifies) his misfire:

https://www.youtube.com/watch?v=zR3ZrwdylPg

Other Forums

https://www.audiworld.com/forums/

https://www.audiforums.com/forum/

https://www.audi-forums.com/

https://www.audizine.com/forum/forum.php
__________________
2001 A8 D2 FL 3.7 Q - LPG Conversion, Engine: AKC, Gearbox:FBB, Colour:LY5X Aqua Blue pearl effect, Interior:WJ light beige/dark beige valcona leather with burr walnut inserts

My DIY jobs - Replaced alarm horn, Replaced Coolant Temp sensor, Updated RNS-D firmware, Installed Reversing Camera and Digital TV, Dashcam Installation, Retrofitted Rear Blinds, Auto-Dimming Rear View Mirror, Chrome Boot Struts

Sold! 2008 S8 D3 5.2 V10 - Engine: BSM, Gearbox:KLW, Colour:LY7F Suzuka Grey Pearl Effect, Interior:Black/Black with Silver/Black valcona leather with carbon atlas inserts, Bang & Olufsen, Heated windscreen, Soft-close doors, TV, DAB, AMI, Quad Zone, Auto Boot, Auto dim Mirrors, Keyless entry, PDC with rearview camera, AFS II Headlights

My DIY jobs - Fan Jet Windscreen Washers, Retrofitted Electric Side Blinds
Reply With Quote
  #26  
Old 19th April 2022, 12:15 PM
ulfilias ulfilias is offline
Senior Member
 
Join Date: Apr 2009
Location: Peterborough, Cambs, UK
Posts: 948
Default

Quote:
Originally Posted by JG27 View Post
I'm having the same issue with my 2.7T - could you please help what do you meant by "inlet flap"?
This "misfire" issue was just how it presented in VAGCOM, mainly on the LPG fuel side of things and caused me to go right through the engine tracking and trying things.

The 4.2 petrol V8 is quite a complex beast and the onboard error stuff is actually pretty basic, so agree with steamship, you'd probably do better elsewhere as this place is great for A8/S8 stuff, but we've not got much experience on other things!
__________________
Current :
2005 A8 Sport 4.2 V8 D3 - LPG working!

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 (Post Apocalyptic makeover)
2003 Brabus Smart FourTwo (should sell)
2003 Mazda Rx8 2.3 (might sell)
Reply With Quote
  #27  
Old 4th May 2022, 03:56 PM
Prefferle Prefferle is offline
Senior Member
 
Join Date: Apr 2017
Location: Scarborough, North Yorkshire, England
Posts: 100
Default

Quote:
Originally Posted by ulfilias View Post
Hi There,

I'm trying to get the LPG install working and struggling. On LPG I get a missfire on Cylinder 8.

I know LPG tends to show up faults in cars that petrol is less fussy with and that's what i'm thinking as it's fine on Petrol.

I've changed all the coils and all the spark plugs. I've just swapped coil and pack from 8 (back left) to 5 (front left) with no change at all.

However we've also tried running injector from 8 onto 7 & vica versa which is saying the car, but.....Well what else can cause misfires???

Vagcom codes :

P0300 Random/multiple
P0308 Cyl 8

Any ideas ???


Lee
Hi Lee well itís going to be fuel, spark or compression. Not sure what engine you have but for me with a similar issue turned out to be a vacuum leak caused by defective the oil separator valve, but that was on a BSM Engine. You may want to check all your vacuum lines and breather as another possibility. Cheers
__________________
Present cars
Daily driver: BMW e65 730d
Batmobile: 2006 S8, D3, 4E 5.2L V10 BSM with (loud) Miltek SS exhaust, Carbon Fibre trim, Alcantara headlining, soft close and keyless entry.
Reply With Quote
  #28  
Old 5th May 2022, 11:48 AM
ulfilias ulfilias is offline
Senior Member
 
Join Date: Apr 2009
Location: Peterborough, Cambs, UK
Posts: 948
Default

Quote:
Originally Posted by Prefferle View Post
Hi Lee well itís going to be fuel, spark or compression. Not sure what engine you have but for me with a similar issue turned out to be a vacuum leak caused by defective the oil separator valve, but that was on a BSM Engine. You may want to check all your vacuum lines and breather as another possibility. Cheers
Bit of an OLD thread here. Fixed some years back. Was an issue with the "coolant" lines, a bit of a BODGE job by the MEH installer, which are used to by the vaporiser to convert the LPG liquid into a gas, as such it was like the system was starved by fuel causing the misfires

Everything appeared fine, apart from the engine codes, it was getting fuel, but not in the right form to spark properly!
__________________
Current :
2005 A8 Sport 4.2 V8 D3 - LPG working!

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 (Post Apocalyptic makeover)
2003 Brabus Smart FourTwo (should sell)
2003 Mazda Rx8 2.3 (might sell)
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT. The time now is 02:17 PM.


Powered by vBulletin® Version 3.8.0
Copyright ©2000 - 2022, Jelsoft Enterprises Ltd.