The car recently began stumbling under load. Took it to a store and had the codes pulled. #3 misfire and random mis-fire codes came up. I had purchased the car (08 Sport) @ 106K with no history (now at 120k) so I decided to change all four coils and plugs. Used Beck/Arnley 178-8284 coils with a small amount of Permatex dielectric grease on the boot and NGK IZFR6K13 plugs.
Started the car and ran for maybe 20 seconds and all is good. Left an hour later to run an errand and within 150 yards the CEL came on then began flashing.
I don"t own a scanner (yet) and am at a loss to identify what I may have done wrong on such a simple parts replacement. Any suggestions?

 

Seems like you know what you were doing. I don't know how the computer determines there is a mis-fire. If everything is hooked up and grounded it should be working if the coil packs / plugs are FIT compatible.

 

Yeah, I am at a complete loss to understand what might have happened since it is such a simple procedure and the check engine light has never come on during the 20 months I have owned the car. But a flashing cell is supposed to be a signal of serious, imminent failure. I have ordered a scan tool that should be here by Wednesday so I think I will just have to let it sit until then.

 

Around here, AutoZone and Advance Auto parts stores will come out and read CEL for free. Honda seems to have their own hi-power device that will allow you to program new ignition keys, etc.

Let us know what you find out.

 

Years ago, I too had the misfire codes but on #2 & #3 on my 2011 Sport AT.

In the beginning, my gas mileage was slowly getting worse and I would smell gasoline fumes upon start up. Then the Check-Engine-Light (CEL) started coming on. And for some reason my Vehicle Assist System (?) starting coming on too. So, I went into diagnosis mode thinking something was wrong with the VAS that helps me keep traction when driving in the snow (winter at the time). Very confusing.

I took it to a local Advance Auto store (they and AutoZone read codes for free) and provided the misfire codes but it was just on #2. Then the CEL & VAS would go out for a day then come back. I found out later that the misfire codes also trip the VAS, so there never was an issue with the VAS just the misfires.

I bit the bullet and took too the dealer and their diagnostics ($60) was misfire #2. It needs a coil pack ($160) and that is $50 labor (total = $270 plus my inconvenience). I asked them to provide my old / broken coil pack. When they gave it to me, it reeked of gasoline and it was sooty looking but I just bagged & tagged and left. 2 days later, the CEL was back on and Advance Auto said that the codes indicated that there was a misfire on both #2 & #3. When I called the dealer the guy remarked that I needed new coil packs. Like hell!

So, I did the old left arm reach-around and started removing wires and coil packs and spark plugs starting with #1. When I got to #2, the coil pack smelled like gasoline and the spark plug was real loose. Same with #3.

I numbered everything and got out the original "broken" #2 coil pack and put it back in after removing the "new" #2 coil pack from use. Everything worked great, so it was the loose #2 & #3 spark plugs that caused the misfire.

I then decided to change the spark plugs (~30K miles which in retrospect was wasteful) if I was going to take apart the wipers/ wiper transmission, plastic air box that feeds the air conditioner / heater, so I could properly torque each spark plug. I assumed that the loose plugs were a factory problem since I had car from new and the dealer never touched it after the first oil / filter change dine under warranty.

After I completed the new plugs and still using the the original coil packs (newest coil pack sits in a box), less than 500 miles later I'm getting a misfire #2 again. I again reach in with the left arm and #2 plug is loose again after properly torqueing.

I decided to use a little Permatex blue threadlocker on each spark plug and just hand tighten without taking apart the car's plastic air conditioner / heater / wiper box again. It continues to operate without a CEL / misfires for the last 30K miles.

So, I would reach in there and check to see if each spark plug is still tight. I really think that the spark plug socket threads in the head are messed up on #2 & #3 because if people do have a problem, it always seems to be with these two. Maybe it is due to heat / cold cycling on that part of the head, but that's the usual problem area.

Best of luck

 

It is hard to say if thread was messed up without looking on it or checking it with go/no go thread plug.
Take a picture of old plugs around crush washer area!
"Proper torque" may not be enough to flatten it.
However I am more convinced that this is a problem with the threads in the head because:
1990 Camry v-6 had partially threaded plug (not two turns not tightened by distracted mechanic) the exhaust damaged the wire boot but plug stayed in place. I installed replacement plugs (and one good used wire) with no incidents after that.
1987 Camry had plugs installed but not tightened (crush washers were not deformed; the car run like this for 15,000 miles without loosening plugs)
IMHO Honda quality is now comparable to 1986 Hyundai Excel
Better to buy vintage Russian car now




One in the USA: 1973 Moskvitch 412<br/><br/>This 1973 Soviet IZh / Moskvitch 412 is said to have only 36k original miles and is described as being the only one registered in the USA. The seller adds that he imported it from Russia two years ago, and that it is almost entirely original and in running condition. While most of its appeal may come from the novelty factor, it must also gain points for being perhaps the ubiquitous background Communist car seen in a hundred Cold War movies.

 

Plugs removed were firmly screwed in.
New plugs installed with torque wrench to 16 ft/lb

After R&R of plugs and coils the car ran beautifully, very smooth.
Then the CEL comes on solid and a few seconds later goes into
flashing mode.
I'll have a code reader tomorrow and let you know what I find.
Old plugs in photo below.

 

From this angle it is hard to see if the washers appear to be fully compressed; can you post a side view of the plug in question? (like this)

 

[QUOTE=doctor J;1372843]From this angle it is hard to see if the washers appear to be fully compressed; can you post a side view of the plug in question? (like this)

doctor J: I submitted a reply with a pic last night but for some reason I got a notice that it was going to be reviewed before it was posted. At any rate, the washers are in fact fully compressed and at any rate they were the ones that had been in the engine when I was getting P0301, P0302 and P0300 codes not the ones I installed prior to the CEL coming on and flashing. I have not pulled those yet as I have been tied home with home projects that are more important to my significant other at this time.