Adventures with bad ignition coils...
- Thread starter Dynamo
- Start date
zeph
Member
- Car
- 2005 FX35 AWD
Hello,
my wife's 2005 FX35 was diagnosed with this problem and we have some questions, but let me start from the beginning:
In November 2010 my wife had roadside trouble and the AAA guy replaced the battery, but not without warning her that the alternator looked bad and advising to bring the car in for service.
In January 2011, she took the car to the Infiniti dealer, with a note from the AAA mechanic describing the issue. The dealer checked and serviced the car, and found everything okay. The invoice details reflect this.
In June 2011, she took the car in again, this time because another mechanic had noticed the left axle was bad. She had a general inspection performed as well, and the car was given a clean bill of health.
Two weeks ago, the car failed on us. We had it towed to the dealer and were told that there was a multiple misfire. Upon further inspection, it turned out three ignition coils had gone bad. Possibly because of bad battery cables, said the rep, as those were bad as well.
What's more, upon replacing the three ignition coils, the dealer found that the engine computer had been fried and needs to be replaced as well. We're gonna be out $1100 for the three coils and $1400 for the computer.
Somehow we feel something does not add up. Reading this thread makes me feel that the January 2011 inspection should have averted this problem. Do we have a case or is this just something that happens to cars, as the dealer says?
Thanks.
my wife's 2005 FX35 was diagnosed with this problem and we have some questions, but let me start from the beginning:
In November 2010 my wife had roadside trouble and the AAA guy replaced the battery, but not without warning her that the alternator looked bad and advising to bring the car in for service.
In January 2011, she took the car to the Infiniti dealer, with a note from the AAA mechanic describing the issue. The dealer checked and serviced the car, and found everything okay. The invoice details reflect this.
In June 2011, she took the car in again, this time because another mechanic had noticed the left axle was bad. She had a general inspection performed as well, and the car was given a clean bill of health.
Two weeks ago, the car failed on us. We had it towed to the dealer and were told that there was a multiple misfire. Upon further inspection, it turned out three ignition coils had gone bad. Possibly because of bad battery cables, said the rep, as those were bad as well.
What's more, upon replacing the three ignition coils, the dealer found that the engine computer had been fried and needs to be replaced as well. We're gonna be out $1100 for the three coils and $1400 for the computer.
Somehow we feel something does not add up. Reading this thread makes me feel that the January 2011 inspection should have averted this problem. Do we have a case or is this just something that happens to cars, as the dealer says?
Thanks.
yep same thing with my car. its been at the dealer for 3 weeks now waiting for new computer. don't wast your money buying new ignition coil until ground wire and computer are tested or replace.
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I don't think there is any way that the previous inspection could have given an indication that anything was wrong or about to go wrong with your coils or computer. I'm not an expert but I don't think your alternator had anything to do with the coils and computer failing. I am assuming your car ran just fine since the January inspection until recently, correct? If the alternator had been bad you would have seen other electrical problems like the battery not charging, etc.
I am inclined to agree with the dealer. When I took my FX in the tech told me that he has seen computers go bad with the same issues and that I was lucky mine was still ok so I don't think they are BS'ing you. My coils just started going bad out of the blue and would have continued going bad if I had not learned about the battery cable TSB and had that done. I would never have guessed it was bad grounds through the battery cables as they looked just fine with no corrosion at any of the connection points. Electrical & electronic components can be like that, fine one minute then bad the next with no warning in between.
I ended up paying $1600 total but that included installation of 6 new coils, 6 new spark plugs, and the 2 new battery cables. Replacing all of that is a pretty easy job (I had already replaced 3 coils myself) and I could've done all of it myself for half as much. I paid the dealer to do it though because I was worried that they might deny the warranty claim for the catalytic converters if I didn't throw them a bone and I also wanted the warranty for the coils/plugs/cables just in case those didn't fix the problem. I got 2 new catalytic converters out of the deal so I'm not complaining too bad.
My FX is still running great since the work was done and I haven't had any other problems since.
zeph
Member
- Car
- 2005 FX35 AWD
Thanks both for taking out the time to reply.
I was not around, but my wife did complain about the engine not running smoothly and told the dealer as much when she took it in for service in June.
But I guess we're gonna have to take this one as it comes.
I was not around, but my wife did complain about the engine not running smoothly and told the dealer as much when she took it in for service in June.
But I guess we're gonna have to take this one as it comes.
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Were there any codes present (check engine light on) during the June visit? What all did the dealer do at that time? How did it feel after that visit?
When my coils went bad a misfire code was thrown for the cylinders with the bad coils. The engine was running noticeably rougher (feels like it is out of balance) and I'm guessing it was also put into "limp home" mode because it was way down on power.
Like I said though, there was no warning at all. I was driving along and all of the sudden it starts running rough, feels like it is down 50% on power, and the check engine light comes on (flashing).
zeph
Member
- Car
- 2005 FX35 AWD
The June visit was for a bad axle, but my wife did tell them that the engine sounded weird. I was not around at the time.
The way you described it, is how it happened to us. It has been fixed and we're gonna pick it up today. We're not happy with the charges though.
zeph
Member
- Car
- 2005 FX35 AWD
No. We got our car back last week. But they charged us $600 for 4 ignition coils, $500 for labor and $1200 for the computer. At least we got two weeks of loaner car (G37) fun out of it.
Somehow we feel this could have been avoided/averted, but we don't have enough to go on to make a case.
Sorry for the late reply.
Somehow we feel this could have been avoided/averted, but we don't have enough to go on to make a case.
Sorry for the late reply.
zeph
Member
- Car
- 2005 FX35 AWD
Turns out the story isn't over yet.
As mentioned before we got the car back, but last week the "service engine soon" light came on and stayed on. We took it back to Infiniti yesterday, and it was diagnosed as a dying catalytic converter. Good news is, it will be replaced under warranty.
Just weird, how this very thread mentioned the danger of catalytic converters going bad with these symptoms and then it actually happens to us.
As mentioned before we got the car back, but last week the "service engine soon" light came on and stayed on. We took it back to Infiniti yesterday, and it was diagnosed as a dying catalytic converter. Good news is, it will be replaced under warranty.
Just weird, how this very thread mentioned the danger of catalytic converters going bad with these symptoms and then it actually happens to us.