Hi everyone

I'm getting an engine misfire along when the car is in idle along with an emissions error. I think it only crops up when the car has been running for a while and will clear after being run at short drives a few times. I'm not certain of this, though. I am certain that it will start off with just an occasional misfire and then get quite steady. Plugging a code reader indicates a voltage mismatch. The battery has been suggested as one possible fix by the AM service manager. I'm curious about that as a fix since I think the battery would have been charged while the car is running. I'm also curious if this is something that requires changing out the ignition packs and if you're in there, why not do the spark plugs as well. The latter seems to be more inline, but being the service manager, I'm not going to rule out his advice at all.

First, what are the thoughts on either solution? Second, if I need to do pack/plug replacement, what is the best way to find part numbers/manufacturers that are the suppliers for OEM parts? I've unfortunately just been informed that my hours have been cut, so price is going to matter.

Thanks

 

if the battery was less than two years old, i wouldn't suspect it to be the source of the problem. but if in doubt, then service centers that sell batteries will test it for free, although being the skeptic that i am, let's just say that i don't believe entities that have a financial interest in the outcome of test to be unbiased. but it is sort of the "go-to" first step involving potential electrical issues these days as ECUs and other electronic devices with processors have narrow tolerances WRT voltages.

i suspect that a misfire may ALWAYS be accompanied by an emissions error. it only makes sense. so i would dismiss its significance until the misfire is fixed. if changing the plugs will be a DIY job, one of the simplest and cost-effective things to do is to put in new plugs. as long as one doesn't insist on ones from a box with an aston label on it.

 

What is the exact error fault codes stored? (not just the description)

 

P0137

 

Full list:

P0130 Bank 1/Sensor 1
P0137 Bank 1/Sensor 2
P0150 Bank 2/Sensor 1
P0137 Bank 1/Sensor 2 Low voltage

 

Here's the AML description for all your codes:

• P0130: Bank 1 Sensor 1 HO2S Open and short to ground circuit malfunction.
• P0150: Bank 2 Sensor 1 HO2S Open and short to ground circuit malfunction.
• P0137: Bank 2 Sensor 2 HO2S Open and short to ground circuit malfunction.
• P0136 (odds are this is your code and not another P0137): Bank 1 Sensor 2 HO2S Open and short to ground circuit malfunction.

In simple terms, you have 4 oxygen sensors, and all 4 of them are flagging open circuit or short to none(break in wire or chaffed through wire insulation to raw metal/chassis ground). None of these codes mean just low voltage, these codes mean there's little to NO voltage.

All the sensors share battery voltage from engine bay fuse box, #18 fuse in the engine box feeds all 4 sensors to connector pin #1. So, if you split open an O2 connector with key on, you should see 12v on your DVOM if checking pin #1 to a ground/chassis. If you don't see 12v, check resistance to ground and then trace the wire upstream for any damage to fuse #18 in the engine bay fuse box.