V12 Misfire & Cat ingestion
Discussion
Felonious said:
Mine's a keeper and I went for the BR manifolds and sports secondaries
...
Also, it sounds (according to a friend) better than any road car he's ever heard. Like a Pagani, apparently. I'm personally very happy with the work done and the outcome (although my motives were unrelated to the thread topic).
Did you get the full custom manifolds from BR? I understand there's options for baritone or higher pitch sound - why did you go for? Would love to hear what it sounds like if you have a video...
Also, it sounds (according to a friend) better than any road car he's ever heard. Like a Pagani, apparently. I'm personally very happy with the work done and the outcome (although my motives were unrelated to the thread topic).
magycks said:
Did you get the full custom manifolds from BR? I understand there's options for baritone or higher pitch sound - why did you go for? Would love to hear what it sounds like if you have a video
Yes, the full Monty. I started with the baffled sports cats but it actually sounded pretty terrible. Mike was concerned as well, but wanted me to decide for myself. I then went for the unbaffled cats, which was much better. It can be a bit boisterous when the valves open but the three-way switch means that you can be quite understated when you want to be. This is in boisterous mode: https://youtu.be/HD_JCdJb-7Y
db11far said:
Update 2: Two loose pins in their respective connectors found on inspection by dealership. Loom and connectors all replaced. Misfire seems to be gone for now AM guys great all around. Hopefully permanently fixed - early days still.
The wiring loom replaced? 
But as for the 'connectors' thing, that gives me bad memories of a well-known independent (former dealer) changing coilpack connectors to fix the gearbox...
karatemaserati said:
felonious can you tell me your full BnR setup ?? im about to pull the trigger on BnR power upgrade and i want the baritone sound
Sorry for the delay, I only just saw this. I have the BR manifolds and sports secondary cats. It's phenomenal and blisteringly, terrifyingly quick. To be clear, it's also quite loud so I find myself driving in a variety of options - Sport for the responsiveness but valves closed to avoid being really loud over 3k rpm, quite often not in Sports at all and pootling quietly but my default tends to be 'standard' valve config in Sport and changing up at 3k just when the valves start to open. There's a lovely burble as the revs drop back below 3k.Also worth noting, I was in an MD yesterday and they had two V12s in with goosed engines due to cat break-up and lumps of brick getting scavenged back into the engine. They said they were seeing more and more of this. Personally I'm happy to not have any risk of this issue.
Felonious said:
Also worth noting, I was in an MD yesterday and they had two V12s in with goosed engines due to cat break-up and lumps of brick getting scavenged back into the engine. They said they were seeing more and more of this. Personally I'm happy to not have any risk of this issue.
We have been told on here, that AML can no longer supply new or rebuilt (VH) V8 engines.
Wonder what the parallel current situation is with V12s ?
If an MD cannot obtain an engine, (irrespective of warranty), they presumably eventually send the car back to the owner, for use as a static piece of art.
Jon39 said:
We have been told on here, that AML can no longer supply new or rebuilt (VH) V8 engines.
Wonder what the parallel current situation is with V12s ?
If an MD cannot obtain an engine, (irrespective of warranty), they presumably eventually send the car back to the owner, for use as a static piece of art.
The cost for a refurb swap-out V12 I am told is around £15k, and as far as I am aware they are still available.
The best $20 you will ever spend if you own an Aston V12 is on a simple OBD reader. This will tell you if you have a consistent or random misfire. A consistent misfire on the same cylinder is likely a bad plug or, less likely, a coil driver.
Continuing to drive on a persistent misfire (Check Engine Light / CEL on). This is what leads to Cat break up and ingestion.
The ceramic works its way through the whole engine.
AML no longer offer Engine exchanges/replacments. There is an alternative coming from an outside and highly respected vendor worked up with a team of Vanquish owners. The short block rebuild will solve the, generally unknown, one Achilles Heel of the V12, the liners. This is what starts "The Dreaded Tick".
The Team have, by accident, adopted the same solution Prodrive used to make the DBR9s last.
The Achilles Heel is this.
and has been found on every DB7, VQ or DBR9 block tested.
Continuing to drive on a persistent misfire (Check Engine Light / CEL on). This is what leads to Cat break up and ingestion.
The ceramic works its way through the whole engine.
AML no longer offer Engine exchanges/replacments. There is an alternative coming from an outside and highly respected vendor worked up with a team of Vanquish owners. The short block rebuild will solve the, generally unknown, one Achilles Heel of the V12, the liners. This is what starts "The Dreaded Tick".
The Team have, by accident, adopted the same solution Prodrive used to make the DBR9s last.
The Achilles Heel is this.
and has been found on every DB7, VQ or DBR9 block tested.
NSP said:
Is it possible to remove the primary cats and leave the factory secondaries in place rather than having aftermarket high flow secondaries installed? If so, does anyone know what this costs?
Yes it is but Bamford Rose are the only ones I know of who would do this and they do generally recommend replacing the factory secondaries in conjunction with removal of the primaries.Felonious said:
Sorry for the delay, I only just saw this. I have the BR manifolds and sports secondary cats. It's phenomenal and blisteringly, terrifyingly quick. To be clear, it's also quite loud so I find myself driving in a variety of options - Sport for the responsiveness but valves closed to avoid being really loud over 3k rpm, quite often not in Sports at all and pootling quietly but my default tends to be 'standard' valve config in Sport and changing up at 3k just when the valves start to open. There's a lovely burble as the revs drop back below 3k.
Also worth noting, I was in an MD yesterday and they had two V12s in with goosed engines due to cat break-up and lumps of brick getting scavenged back into the engine. They said they were seeing more and more of this. Personally I'm happy to not have any risk of this issue.
So a bit of humble pie consumption in order from the posters in the past who said they’d never heard of anyone having this problem & that catalyst ingestion scare stories were just a marketing ploy by a well known Aston Indie.Also worth noting, I was in an MD yesterday and they had two V12s in with goosed engines due to cat break-up and lumps of brick getting scavenged back into the engine. They said they were seeing more and more of this. Personally I'm happy to not have any risk of this issue.
Caslad said:
NSP said:
Is it possible to remove the primary cats and leave the factory secondaries in place rather than having aftermarket high flow secondaries installed? If so, does anyone know what this costs?
Yes it is but Bamford Rose are the only ones I know of who would do this and they do generally recommend replacing the factory secondaries in conjunction with removal of the primaries.I've had my primaries removed by BR and kept the standard secondaries, like Andy I was worried about the ingestion issue.
My DB9 is an early 2004 and so inside the DB9 dreaded tick time period, but (touch wood) has no ticking problems, i'm hoping she'll avoid that problem as the repair will be way more than what I can pay, and changing the engine myself looks like a job too far!!
On youtube there's a guy in the US who is replacing his DB9 engine in his garage at home, https://www.youtube.com/@GB9Garage
On another note, some early V12 owners upto when Aston started using the 3 pin coils are now experiencing a rough idle even when all the coils are in good condition because Aston found out the coil units aren't grounded well inside the engine, causing a rough engine idle so they improved the design and installed 3 pin coils with the 3rd earth ground wire, I think my car is now suffering with this even after installing genuine coils/plugs recently but it's not that bad and she drives great,
My DB9 is an early 2004 and so inside the DB9 dreaded tick time period, but (touch wood) has no ticking problems, i'm hoping she'll avoid that problem as the repair will be way more than what I can pay, and changing the engine myself looks like a job too far!!
On youtube there's a guy in the US who is replacing his DB9 engine in his garage at home, https://www.youtube.com/@GB9Garage
On another note, some early V12 owners upto when Aston started using the 3 pin coils are now experiencing a rough idle even when all the coils are in good condition because Aston found out the coil units aren't grounded well inside the engine, causing a rough engine idle so they improved the design and installed 3 pin coils with the 3rd earth ground wire, I think my car is now suffering with this even after installing genuine coils/plugs recently but it's not that bad and she drives great,
Edited by paulrog1 on Thursday 25th May 20:53
Caslad said:
NSP said:
Is it possible to remove the primary cats and leave the factory secondaries in place rather than having aftermarket high flow secondaries installed? If so, does anyone know what this costs?
Yes it is but Bamford Rose are the only ones I know of who would do this and they do generally recommend replacing the factory secondaries in conjunction with removal of the primaries.Anyway come the time that my primaries fail (hopefully never) then the QS header would be my choice over a chop job.
https://quicksilverexhausts.store/collections/asto...
NSP said:
Is it possible to remove the primary cats and leave the factory secondaries in place rather than having aftermarket high flow secondaries installed? If so, does anyone know what this costs?
Yes, this is perfectly possible. I’d imagine it’s just a little bit less than the BR decat + high flow secondaries package. AdamV12V said:
Quicksilver also make a replacement new manifold set, but it does come with sport secondaries, but if you replace the headers then you need a solution for where to place and connect the knock sensors, although if you do the BR chop job then that's not an issue. AM dealers will fit the QS solution with a little nudging I found, but to be clear neither solution is AM approved. However if your car is well past the point of any goodwill or warranty then thats not an issue either.
Anyway come the time that my primaries fail (hopefully never) then the QS header would be my choice over a chop job.
https://quicksilverexhausts.store/collections/asto...
Keep in mind that the sound will be different on all these. I compared mine side-by-side with someone with the Performance Pack 2 (new inlet manifolds, same primaries, sports secondaries and titanium pipes). The Aston option was a deeper sound. Velocity AP is very shrill (https://www.youtube.com/watch?v=5xBarRft-fk), which I personally don't like at all. So always try to hear what you're buying before you buy it as results will vary. Also, the back box apparently varied through the life of the car, so there's another variable to factor in.Anyway come the time that my primaries fail (hopefully never) then the QS header would be my choice over a chop job.
https://quicksilverexhausts.store/collections/asto...
Gassing Station | Aston Martin | Top of Page | What's New | My Stuff