So after misfire learn process
This morning I had to start car two three times
It failed to start on one attempt
So I guess it's the coil
How much sea foam in a full tank of gas should I put?
I have a gallon of sea foam sitting at home
You pour it in to gas tank right?

 

I had a retail size that went into about a 3/4 full gas tank, based on the directions on the can.

 

I've heard a lot of people say they love Seafoam, but I've never used it. There are a few products out there that are along the same lines. One of the main issues we face in the US is the crappy quality of our gas. I can rant all day about ethanol in gas (it's bloody horrible), but I'll spare you all that lol


There are a couple places to put it in - the gas tank, a vacuum hose, and somewhere else, I think.


When you use it, keep in mind that there's likely to be a massive cloud coming out of your exhaust!

 

Update. ~40K miles. New coils, plugs, PCV valves. Smooth idle, no hesitation or stumbling at low RPMs. Drives like new again.

FWIW my February 2006 DB9 (VIN ending 5514) has 3 pin coils. Not sure if that's a reliable guide for ordering parts though.

 

Not just coils and plugs can cause your issue, as Telum01 sayed, bad gas, clogged or partially clogged injectors, clogged EGR valve and a dieing MAF can also cause these issues, along with other sensors.

Seafoam is like snake oil to me, it has never been proven to do some of the thens the bottle claims. Only real way to clean a fuel system is to take out injectors and have them refurbished by a qualified shop, replace seals and filter.
I know a lot of people put faith in Seafoam, but I am one of those who wants proof.

 

For what it's worth, I looked into injector cleaning/rebuilding/flow matching, and the cost was about the same as just buying new injectors.

 

Start Running Shell Nitrogen Enriched 93 and replace the MAF Sensors first before opening the fuel system. Once you clean them chances are they are permanently fouled. Also, if the Misfire correction is required it's best to either strap it to a dyno and run the sequence five or six times or have the dealer flash it. A bad coil or fouled plug should throw a fault.

Below is a quote from the Babcox Counterman website

http://www.counterman.com/understand...r-flow-issues/

"If a technician elects to clean a dirty MAF sensor, it’s important to recommend that he use a specially formulated MAF sensor cleaner. Using carburetor cleaner or other harsh solvent will destroy the sensitivity of the sensor. Keep in mind that cleaning won’t always restore perfect calibration. For this reason, many technicians prefer to replace fouled MAF sensor assemblies."

 

So my 2009 dbs manual has a little hesitation as described in this post.
it only has 30.000km. On the clock.

how can I do the misfire procedure with a manual?

It’s got the be the maf or coils and plugs.
like to find the problem if I can diagnose it with the misfire procedure.

 

All the same as an auto, just leave it in 6th gear...

https://aston1936.com/2016/03/18/rel...on-martin-db9/

 

Thanks Yvr. Not it if it’s the mag sensors or coils. 30k seems a bit early for sparks and coils. But I know they eat coils.