LEDAdd1ct
Flashlight Enthusiast
I have a problem with my car which is driving me bonkers, and I am hoping someone here can assist. The story goes like this:
A few years ago, my "Service Engine Soon" light in my 1999 DOHC Mercury Sable (Taurus) came on. I was told it wasn't a serious issue, and let it go for awhile. When I was able, I had all the plugs and wires changed, and the technician turned the light off. However, miles later, it came on again. The code was the same, "Cylinder Six Misfire." I used the computer from Autozone to read the code and turn it off, and it went away for some time.
Recently, it came on again, same Cylinder Six Misfire, but I noticed over a period of months that the car was shaking with a rough idle. When you drive, when you accelerate, you don't feel it at all, but when you are sitting still, you definitely do. I brought it in to a local branch of a national chain of auto repair shops, and they diagnosed it as a bad coil pack. They swapped the coil pack, but told me that there seemed to be a lot of carbon buildup in cylinder six, and though the new coil pack would make it fire, it still wouldn't be 100%. They advised me to go for a long drive over the weekend.
A couple weeks ago, I did a 250 mile loop, with the "Service Engine Soon" light still on. I added fuel injector cleaner prior to the drive, in the hopes of removing the carbon buildup in the cylinder. However, the car still idled rough, and when I paused during the trip to snap some photos, the tachometer fell low and the car almost felt like it would stall out.
I brought it back, and they did some rerouting to isolate the cause, pointing spark plugs to different places. They said that the plugs and fuel injectors were working properly, and that since the code was reappearing on cylinder six, it was probably just dirty.
I do not know if this is related, but when I drive, there is a ticking noise coming from the bottom left. The mechanic said he didn't see anything odd from the bottom of the vehicle. When I drive faster, the ticking increases. It is never present when I stop, as the frequency of the tick follows the velocity of the car, and goes away whenever I apply the brake. When I brake, the ticking vanishes. The last time I was in, the mechanic told me that when I use a computer at Autozone, it reports a code that is already there, while their more advanced computer can read data while the car is running. He said the reason the "Service Engine Soon" light didn't turn on is because while it was still misfiring, it hadn't reached the level of being serious enough to reactivate the light. This evening, with my gas running low, the "Service Engine Soon" light once more illuminated. I have no doubt that when read, it will indicate, once again, "Cylinder Six Misfire."
At this point, I don't know what to do. While I can assemble a computer and know a little bit about flashlights, my knowledge of cars is lacking. I have a new coil pack, which may have reduced the issue, but the shaky idle is still there. When I am at rest, I can see the car's incandescent lights gently throbbing on the wall. So, 1999 DOHC Mercury Sable, 126,000 miles, plugs and wires changed, new coil pack, persistent cylinder six misfire. I googled vacuum leaks, but the articles I pulled up state that a vacuum leak would impact all the cylinders, not simply one. I am not in a position to continuously drop money into solving this, but I have found the members of this forum to possess a depth of knowledge that often exceeds that of the average man or woman on the street. My dad has a Taurus wagon of a similar vintage with 150,000+ miles, and it does not shake when idle or stopped.
I would appreciate any constructive advice. Googling returns a thousand possibilities.
If there is any other information I can supply, I will happily oblige. There are things that may seem obvious to persons in this field which I would never consider.
Thank you!
A few years ago, my "Service Engine Soon" light in my 1999 DOHC Mercury Sable (Taurus) came on. I was told it wasn't a serious issue, and let it go for awhile. When I was able, I had all the plugs and wires changed, and the technician turned the light off. However, miles later, it came on again. The code was the same, "Cylinder Six Misfire." I used the computer from Autozone to read the code and turn it off, and it went away for some time.
Recently, it came on again, same Cylinder Six Misfire, but I noticed over a period of months that the car was shaking with a rough idle. When you drive, when you accelerate, you don't feel it at all, but when you are sitting still, you definitely do. I brought it in to a local branch of a national chain of auto repair shops, and they diagnosed it as a bad coil pack. They swapped the coil pack, but told me that there seemed to be a lot of carbon buildup in cylinder six, and though the new coil pack would make it fire, it still wouldn't be 100%. They advised me to go for a long drive over the weekend.
A couple weeks ago, I did a 250 mile loop, with the "Service Engine Soon" light still on. I added fuel injector cleaner prior to the drive, in the hopes of removing the carbon buildup in the cylinder. However, the car still idled rough, and when I paused during the trip to snap some photos, the tachometer fell low and the car almost felt like it would stall out.
I brought it back, and they did some rerouting to isolate the cause, pointing spark plugs to different places. They said that the plugs and fuel injectors were working properly, and that since the code was reappearing on cylinder six, it was probably just dirty.
I do not know if this is related, but when I drive, there is a ticking noise coming from the bottom left. The mechanic said he didn't see anything odd from the bottom of the vehicle. When I drive faster, the ticking increases. It is never present when I stop, as the frequency of the tick follows the velocity of the car, and goes away whenever I apply the brake. When I brake, the ticking vanishes. The last time I was in, the mechanic told me that when I use a computer at Autozone, it reports a code that is already there, while their more advanced computer can read data while the car is running. He said the reason the "Service Engine Soon" light didn't turn on is because while it was still misfiring, it hadn't reached the level of being serious enough to reactivate the light. This evening, with my gas running low, the "Service Engine Soon" light once more illuminated. I have no doubt that when read, it will indicate, once again, "Cylinder Six Misfire."
At this point, I don't know what to do. While I can assemble a computer and know a little bit about flashlights, my knowledge of cars is lacking. I have a new coil pack, which may have reduced the issue, but the shaky idle is still there. When I am at rest, I can see the car's incandescent lights gently throbbing on the wall. So, 1999 DOHC Mercury Sable, 126,000 miles, plugs and wires changed, new coil pack, persistent cylinder six misfire. I googled vacuum leaks, but the articles I pulled up state that a vacuum leak would impact all the cylinders, not simply one. I am not in a position to continuously drop money into solving this, but I have found the members of this forum to possess a depth of knowledge that often exceeds that of the average man or woman on the street. My dad has a Taurus wagon of a similar vintage with 150,000+ miles, and it does not shake when idle or stopped.
I would appreciate any constructive advice. Googling returns a thousand possibilities.
If there is any other information I can supply, I will happily oblige. There are things that may seem obvious to persons in this field which I would never consider.
Thank you!
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