gdal

iTrader: (2)

I went out to lunch today and noticed that my car was misfiring. It misfired for a few minutes until the CEL light flashed three times. The misfiring went away immediately.

I stopped by Autozone to see if I could pull the codes and the scanner showed 0 codes.

The car has been running good. the MAF is recent, but the coils are still the factory originals (minus one), which leads me to believe that they are going bad. The plugs were replaced a few months ago.

Is there a way of obtaining a code without the CEL light being on? I was under the impression that the ECU stores the last codes no matter if the light is on or off. I don't want to change all the coils until I'm sure that's the issue.

Any advice?

gdal

iTrader: (2)

Anyone?

Ghost_54

iTrader: (13)

Well your correct about the flashing CEL light which is for the engine having a multi misfire occurrence ... your suggestion of it possibly being one of the coils makes the most sense given they are the original OEM ones ... my understanding is that the ECU will hold a pending not always the one that you just had the best is when the CEL is on to get an accurate read would be my best guess

The multi misfire code would be P0300, if you find you have a particular coil failure it should show up as P0301. P0302 and so on for each cylinder

gdal

iTrader: (2)

Thanks for the response ghost_54 ... I bought 6 coils packs from AutoGeek. They are Hitachi ones, so I think I'll be good. I'll report back.

gdal

iTrader: (2)

well, I noticed the misfire again today on my way back from work. This time it was constant, but it didn't trigger the CEL. I'll be getting my new coils on Monday.

Ghost_54

iTrader: (13)

Just out of curiosity I have a couple of question given there has been a number of the guys pull misfire codes and multi misfires.

1. How is your oil level?
2. How often do you change your oil?
3. What kind of oil are you using .ie dyno oil or synthetic?
4. How many miles on the car?
5. Have you ever had the engine flushed?

I am asking these questions to see if there are any similarities between not only your current engine misfires but what I have read from some of the other guys as well as my own dealings this past summer with multi misfire code P0300. The engine over time will develop a lot of gum/gunk, and varnish deposits inside, and although regular oil and filter changes will help remove some deposits a lot still stays deep throughout the engine. It does take much of an oil drop (in its level) to allow this gum/gunk to get pushed up into the upper workings of the engine and start to clog things up. The variable Timing solenoid being one that has a very narrow passes and these deposit can get lodge in the inner tubing, this being one of the first steps in causing the misfire process to start. Back over the summer my misfire became so bad that my timing was thrown off and I had horrible engine knock. I had tried just about everything short of replacing sensors as the only code I ever got was the P0300 multi misfire. I started changing the oil and filter ever 2500km. had the engine flushed twice, even used seafoam three times over a 4 month period trying to clean up the engines internals. I remembered reading a thread or two here on the .org discussing these causes of P0300 and related misfire codes. One member mentioned using Auto-RX, you can't buy it at the local shops it has to be order directly off the web site (expensive for a 12oz bottle 36.and change) after reading about the product on the web site I decided to give it a try. I must say the product thus far has done what it said it would do, I now have no more incidents of engine knock, the engine timing is back where it was before all my grieve and the engine is a quiet as a mouse and running very strong once again. I have not had one incident of the return of any misfire/multi misfire and no SES warning lights for over 4 months now.

All of the above is purely only my own thoughts and what I have been able to read from the many recent as well as past misfire codes and multi misfire P0300 threads, so again this is only my opinion for what it is worth just seems to be an awful lot of the guys lately experiencing various levels of engine misfiring and I can't help but think other that the failure of a coil pack or bad spark plugs (that are old) the other common element would be the oil and the degree of contaminants within the engine. As our engine age and begin to burn oil more so than other, these engine deposit get pushed up into the engine and start fouling up plugs and engine timing units and are at the heart of all the misfiring that is going on.

Sorry there OP for being a bit long winded in your thread and straying away perhaps from your issue and concerns you have, but I just find it very odd that as we believe we are taking good care of our cars we get plagued with this engine misfiring issue.

Oh almost forgot if you wish to read up on the product Auto-RX here's the link http://www.auto-rx.com/

gdal

iTrader: (2)

1. Oil level is full.
2. I change my oil every 3k-3.5k.
3. Mobil1 with NAPA Gold filters.
4. 89k
5. I haven't had my engine flushed because it's really clean on the inside. I got this car used this past August. I was given all the receipts for the oil changes ... 2.5k changes since it was purchased. I constantly check the valves thru the oil cap opening and the engine is spotless. I've been using LC20/FP60 since I bought it. I also ran BG44k can a few months ago. I also had a BG fuel system cleaning service when I bought it. I have driven it for 8k without issues. I also changed the spark plugs 4k ago.

It has been running like a champ until the first misfire happened last Tuesday. I'm pretty sure it's a coil. It ran fine for a few days and then the misfire all of a sudden happened again.

Ghost_54

iTrader: (13)

^^^ Looks like you have already been using a good internal cleaning regiment, I do understand that an engines misfire can be the result of may different factors, from plugs and ignition coils to bad ground connection in the electrical system. I look forward to hearing that the changing of the ignition coils solves your current misfiring, and your car returns to running like a champ.

gdal

iTrader: (2)

Let's see. I just drove it for 30 minutes without any signs of misfire. I'll keep you posted. Thanks again for all the advice.

joeltender

castrol 5w30 + lucas
215km(130ish mi)
burn 1qt/2500 mi

Had flashing cel p300 at 175000km. got lucky, pulled a p303 second time it happened, only replaced #3 coil, not a problem since. Original coils besides that one. have seafoamed a couple times, only in the engine once - drove only 5 miles with it in the engine though.

gdal

iTrader: (2)

Just got done changing all my coils.

I tested the old ones with a multimeter and it seems that I was running with one bad rear coil. There's a noticeable improvement ... idle is perfect and the engine is more responsive. I'll verify mpg this week. I've been noticing a drop in MPG ever since I noticed the misfiring (which is logical). I think the bad coil was the culprit.