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Just did plugs and coils on AM29 engine. My experience.
Hey all, I went and did the plugs on my car (Rapide S) and while at it, did the coils as I had one that seemed to be misbehaving.
My sources of inspiration were Steve @ Aston1936 , and the Service Manual. Since my car is a little bit newer than Steve's DB9, there were a few tiny variations.
I also wanted to share my cost to doing this and sourcing OEM / ODM parts instead of ordering all of it from AML.
So here goes... 2017 Rapide S Shadow Edition
First is the dissassembly, it's pretty straight forward, take a lot of pictures for routing of the loom.
One thing I did differently, is I removed the fuel rails. To me it was obvious that I was going to get a lot more room to work and not have the injectors / rail in the way and potentially damage them.
Remove the intake manifolds requires a bit of time and care to move them out of the way without scratching anything, but once the throttle bodies are out of the way and everything is disconnected properly, then it comes off without a hitch.
Had a bit of issue figuring out how to disconnect the brake booster line, but Steve @ Aston1936 had it figured out for me. Getting to the last manifold insulator bolts at the back is what took the most time. Also, start with RH side of the engine bay, the LH manifold has its last cylinder further recessed and harder to get to the bolts.
With the fuel line removal tool ($10ea), they come really easy, just have to be ready to catch the fuel. They are sized differently as well, need a different tool size for each, and only go back one way.
I did have to snip the fir clip ties (0.22" wide) for the injector loom off the fuel rail as they get mangled when prying them off with a trim tool. Ordered a pack of 100 online for $14, when I needed 6... but it made for a clean re-install.
Snipped the fir clips off the rail, had to replace all 6
First off, did the plugs. Removing them was straightforward if only the ones at the back are a bit cramped. They were on very tight from the factory.
The OEMs on my car are the NGK SITR7A11G , Catalog # 94949 . I couldn't find them anywhere here in North America, only the local dealer carries them in the Aston Martin white box.
The OEM pack of 4 CD33-12405-AA-PK ($183) comes to ~$45ea
I bought the retail NGK plug for $11/ea
Aston Martin CD33 NGK plug vs Retail NGK 94949. Both SITR7A11G
Then onto with the coils. The square coil is a Ford unit with a longer boot. This has been discussed elsewhere. Since the boots on mine were fine, I went aftermarket.
The Motorcraft part# for the coil is DG562 ( Also available: Denso 6736203 , Walker 9212147, NGK 48770 ,etc ) , and is used on a variety of cars including the Ford Ecoboost engines (2.3L I4) OE Aston Martin Coil (Ford), MSD Coil, Motorcraft Coil (Ford) OE Aston Martin coil
Since they had a sale on, I settled for a set MSD Ignition coils. I've no issues with quality on those specific coils in the past. Main reason was price, not really expecting more 'spark' out of them.
Price wise: the OEM ED23-12A366-AC ~$105 , vs Ford ~$60, vs MSD $42
I twisted the boots carefully off the coils to get them to unstick, added some dielectric grease on the base and put them all back together.
Swapping the boot onto the new COP, bit of dielectric grease for reassembly
And onto the car they went...
For re-install, spent a bit of time cleaning up the intake manifold, removing oil residue from them and throttle bodies.
The intake manifold gasket price almost knocked me out! The single gasket is ~$258 , and the 2 pack kit ( 1R12-08-10077-PK )is between $350 and $430 .. that's nuts!
So, I did as I usually do when seeing price gouging from OEMs, and found my way to save a lot of money there:
Ended up paying ~$125 new for the pair!!
New gasket ($65!) on top, old gasket ($250!) on bottom Lining up 2 Manifold Isolator bolts around the gasket ridge holds it in place for installation
I went per the instructions for installation and mounted the gasket with its 2 ridges with the insulators and made sure they held the gasket properly, did the install in reverse, slowly!
I changed out the lower O-Rings on the injectors. Left the top ones as I didn't remove the injectors from the rail.
The Aston Martin OEMs come in $42 replacement packs of 8 ( 6G43-08-11260-PK ), because it's a Bosch EV14 injector on Ford V8s. Vs Bosch 8 packs for EV14 top&bottom o-rings` $10
So OEM lower O-ring ~$5 each vs Bosch $0.50
Carefully routed and installed the looms as they were originally
Turned the car On to repressurized the fuel line, checked for leaks, then started & stopped the car until it idled smoothly. Took about 5-6 cranks, 2 minutes of total idle time.
Finished by putting back the cleaned engine cover and brace!
At the end of the day, it wasn't a difficult job (except for getting TO stuff at the back of the engien), the procedure is long but just need to follow through carefully.
I was curious what my savings were cost wise on total parts, A total of AML parts total would be $2315 . Since I went the OEM (Ford, NGK, Bosch, etc) route (except coils which were aftermarket) total $761
All in all a good day. and most happy that I've come into some Manifold gaskets at a MUCH discounted price.
I have an earlier 2007 DB9 with the 3 pin plugs - would the Motorcraft coils work? I "think" our engines are the same, with yours putting out a little more power.
This is an amazing write-up, thanks!
How did you get access to all non-AM part numbers?
Is there a website that cross-references these?
There's a couple threads of equivalent parts on here and other forums. It's mostly searching and research. One thing that helps on mechanical parts it the large number of them are Ford sourced, and the Aston Martin part numbering uses the same component codes as Ford.
For example , the Aston Martin coil pack is ED23-12A366-AC . The E prefix is the year code of the part being put into service, here I think it means 2013. The previous 3pin model 8G43-12A366-AA similar, would be put into service around 2008.
So you can tell from the same Aston Martin part about what time that part was being used (not an updated part, but a new version). and the actual part # is 12A366 , so I know that searching for a Ford Part # with a similar date code in 12A366 will likely find something relatable. In this case, I found that Ford CM5E-12A366-CA was the same coil plug and from there worked to get the retail part # DG562 , and then all the equivalent aftermarket offerings are just easy to get.
I have an earlier 2007 DB9 with the 3 pin plugs - would the Motorcraft coils work? I "think" our engines are the same, with yours putting out a little more power.
I think the main difference is the previous 3pin plug are driven from a Ford ECU (Visteon), whereas my car has Bosch ECUs. Your part # looks like it's 8G43-12A366-AA and it's the round type Ford coil. There's a good writeup by Steve @ Aston1936 on his search for aftermarket coils. He did find the right one, but it seemed the boot spring was tacked onto the coil and he didn't find a way to disconnect it and transfer to the new coil. Which is really why my approach worked, the new square coil has a boot spring that's just compressed against the base of the coil, so it's easy to transfer.
There is a company called DM Coil that offers sets of the round 3pin, they are on Amazon
Short story is I bought a bunch of them at discount and selling them as I dont think I'll ever use the quantity I bought!! If you plan on doing a service that requires removing the intake manifold and put off by the gasket price, you should stock up!
Interesting find about ngk spark plugs as the ones op sourced are from uk and difficult to find in the states. According to this ngk 4477 is an upgrade for the v12 db9. But different for the Rapide as the part number is the same as op sourced. Strange that the same engine is requiring different plugs.