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2004 Nissan Altima

This is the previous post I posted “L have a four cylinder 2.5 SE Nissan Altima. I got the car back in April of 2008. I drove the car till October with no problems. In October I had a car audio system installed professionally. two amps, subwoofers and a power capacitor. After the stereo was installed I had a loud hissing noise. I took the car back and the shop put in two ground isolation loops. The next day my car had a check engine light on so I had the code read and it came back with a misfire so. The mechanic I took it said it was a the Number 1 coil. The said they unplugged the wires from the coil and nothing changes and they moved coils around and the problem followed. Ever since this time I can only drive the car maybe 300 miles at the most and it keeps blowing ignition coils. After about 10 coils this guy talked to a Nissan Dealer in denver and the master mechanic said it was an ECM. So the mechanic that has done all this work replaced the coil and the ECM for me and took the car to a dealer to reflash the ECM. Three days later the car died on me and found out that once again it was another coil. I have allready invested at least 3000 in the stupid car and it wont staying running right. I have suggested that it had something to do with an improper wiring on the car audio equipment. I have also tried to pursue the Lemon Law but the attorney I talked to strongly discouraged me away from this saying it would be a waste of my time and money. This car has set my wife and I so far in debt because we cant pay our bills like we used to before the car because we are always sticking at least $300 a pop to keep it running for 3 days or 300 miles. I have no clue what to do anymore. I am thinking it wasn’t a computer to begin with and have even suggested they run down wiring to see if any wires are bad and need replaced. Do you have any suggestions.” How do I get the shop to fix the car. I have talked to two dealerships in bigger cities (Denver and Lincoln, NE) and they are more than willing to find the answer and really dig into the heart of the problem. They have said exactly the same thing everyone in here has. The two dealerships that the car has been to in the past, the techs act like they don’t know what to do or even want to fix the problem. They say “oh its a coil and they replace the coil and act stupid and say they have no clue what to do next”. They are very ignorant and act like they know what’s wrong and if you question them they get all defensive especially when you catch them in a lie or making them replace parts that were under warranty. These dealerships come from towns ranging in size from 20,000 to 60,000 (rapid City, SD and Scottsbluff, NE). Sad thing these dealers are the only Nissan dealers within 2 hours from me. Otherwise the closest dealer is 5 hours away in Denver. I can’t afford to be hauling the car to denver to have it fixed. I told them everything in this post and they keep telling me a coil can’t cause a coil or a plug wire to go bad and the tell me that an audio system couldn’t cause the problem because that is something totally different.

In summary, since you had an after-market stereo system installed, the ignition coils continue to go bad, right?
When you had the stereo system installed, did you have an anti-theft system installed, also? And, does the anti-theft system kill the ignition to prevent theft?
If the anti-theft system is wired into the ignition system, to cut power to the ignition coils (or, other ignition components), that is a potential problem. A couple of car makers have bulletins concerning this problem with such after-market anti-theft systems.
They may have wired the stereo into the ignition system. You may have to have the stereo system disconnected.

Thanks hellokit.  I agree with your guess. 

lakotawicasa73 How about a few paragraphs.  That mass of text looks so difficult to read I chose just to rely on hellokit and may have missed something important.  Paragraphs make reading easier and more people would be likely to read what you write.

The typing here works well if you hit “enter”. It isn’t like e-mail that comes out all wrong, so go ahead everybody; don’t put your posts in like I do. I’ll try to change.

Anything wired into the ignition system can cause ignition problems. If the stereo people made that mistake because they chose a hot wire at random, you could have lots of problems. It doesn’t have to produce a bad coil or other part; it just has to drain the electric power. Sometimes the wire is put into the fuse box with an adapter. I would look for one and see which circuit they used.

no anti-theft system the car allready has a factory installed one with a keyfob.

I assume so. I took out all of the stereo equipment and it still blew at least two more coils before a ECM replacement. After the ECM was replaced it blew one more coil. I have tried talking to two dealerships in my area. the Rapid city SD dealer and Scottsbluff NE dealer and they both act dumfounded and not to willing to find the problem. I agree with everyone I didn’t think it was a coil or computer issue to begin with. I have asked them if they checked the wiring of the audio system when it was installed or if any other wires may have been spliced into and they said yeah they did but thats kind of hard when they diagnose the problem in 20 minutes and say they checked the wiring. I also asked if a plug or wire could have caused the problem and they have said OH NO there is no way that could happen.

After I took out the audio system I wasn’t happy about how they had the amps grounded. They drilled seven holes under the back seat and used about seven little screws to ground an 8 Gauge wire to the chassis of the car. I saw a bigger headed bolts that held in the seat belts and braced in the top of the back seat. I thought they should have grounded their instead of drilling unneccesary holes. At least that is what I would have done if I was installing the system.

Both of these dealers say we don’t know why a coil would keep going bad. I have talked to two other dealerships in bigger cities to ask there opinions. These dealerships come from Denver and Lincoln NE. They were more friendly and willing to solve the problem. Or at least try to. Only problem is they are both five hours away from me and I cant afford to have my car towed all the way there.

Why can’t a local Nissan dealer fix the problem. I am getting tired of the local dealerships (two hours away from me if you call that local) not getting to the root of the problem and fixing it. they just keep replacing coils. I am so ticked that I don’t know who to believe everyone is pointing fingers but nobody wants to FIX the problem. I want the car fixed.

I confronted the car audio shop and they say no it wasn’t our fault we used volt meters and tested the connections. The dealerships say it was the car audio place’s fault. I have always thought it was the car audio shops fault because the car ran fine until I had the system put in the car

It is always possible that the problem wasn’t related to the stereo despite drilling so many holes. The audio place and the dealer will always point at the other guy, but now you would figure that someone can find the problem. That may require some luck. You don’t want anything extra connected to the seat belt bolts. Some shops will not check the wiring harnesses that are in the system because they are not very determined.

Let’s consider the basics. This engine has COP ([ignition] coil on [spark] plug). The engine computer (ECM) triggers each spark by grounding the ignition coil primary wire. (The spark path, and spark plugs, are the “secondary” ignition circuit). The primary trigger voltage is the same as alternator output voltage (13 1/2 to 14 1/2 volts dc). The ignition coil output spark goes through the spark path, and on through the spark plug.
How do the ignition coils fail? They fail from over-heating, don’t they?
What could cause the ignition coils to overheat? If they carry current too long, and / or the current is too high, that would do it.
Check the spark plugs for correct gap and deposits. If wrong gap or have deposits, replace them. Check the spark path for resistance.
Measure the output of the alternator for ac (alternating current) content. If it has ac output, replace the alternator. If dc output is over 14 1/2 volts dc, or under 13 1/2 vdc, replace the alternator.
Measure each ignition coil ground resistance. It should be near 0 ohms.
You may find an independent shop with the expertise to fix this. The dealerships can’t or won’t expend the effort.

thanks hellokit and pleasedodgevan you have been more helpful than the dealerships in my area. I purchased a new plug and waiting to get a brand new coil. I would feel a lot better if I knew for sure that the whole setup (plug, plug wire boot, and coil) was new because then I KNOW and don’t have to take someone one their word. the check engine light came back on but the car is running better than it has in a long time. In the past the light has come on and about 5 min later the light starts flashing . I drove it 15 miles with the light staying steady, no flashing so I guess thats a good sign for now. I just know now not to go back to that car audio place for professional installs

I’m going to agree with hellokit on this one.

Your stereo install, done correctly, or incorrectly, probably stressed a weak charging system, and damaged the alternator.

This alternator probably damaged other components, including the ECM, and the ignition coils.

Up to this point, you have replaced the ECM and the ignition coils.
You should also change the alternator and the spark plugs, and the coil again if it needs it, and possibly keep a new ECM on standby.

Honestly, a new car might be the best solution.
And don’t install a stereo system this time.


Some of the chaiin auto parts stores will read the code, free. Ask them to do that, then, bring that trouble code heredfor cussin’ n discussin’. It could help to get a handle on this critter.

I know someone that has an Ohm Meter I can use so I can check resistance on the plugs. although for the alternator I would have to take that off and have it tested.

I never thought an audio system would cause so much problems. I remember my 98 monte carlo I had the same deck and everything else and it ran fine no problems but then again from what I hear with the Altima it is such a touchy and high tech car that you can’t change anything about it. I have heard with BMW’s that some places wont touch them because the audio system is all fiber optics and you can mess the car up really bad if you install something else. I just wanted a better deck and speakers because the factory deck and speakers sounded like crap. When I had the after factory deck in the car ran great. it wasn’t until I put the two amps, subwoofers and power capacitor in that I started having the problems.

It makes sense if the amps and the rest of the system minus the deck damaged the alternator and ECM. All the extra wattage and volts being produced and putting a strain on the alternator and ECM. Just like it makes sense to me that if a coil goes bad, it could cause the plugs and wires to go bad as well and if those are fixed then its ongoing cycle. I took a couple of course in Physics so I understand a little bit about electricity and resistance not a thorough understanding. I have always thought it was the audio system to begin with but all the mechanics at the dealerships said it couldn’t be.

To be honest I really didn’t want the car to begin with because I knew that getting the car fixed would be a hassle and expensive most of the time. I wanted an 07 Grand Prix but at the time my wife and I couldn’t afford the down payment the dealership was asking. I thought well its a Nissan and they are supposed to be dependable and reliable cars so I gave in.

If properly wired into the car’s electric system, the amps and sub-woofers shouldn’t cause a problem…with one caveat: high power draw. The amps should be wired to the highest power connection in the power distribution box, or, as some do, directly to the battery.
Borrow an ohmmeter?! Why not get an inexpensive (when compared to the cost of an ignition coil) digital multimeter? Then, you could make the ac/dc voltage readings.
The alternator does not have to be removed to have it tested for 1. current capacity, at idle and above 1,000 engine rpm, 2. dc and ac voltages at idle, and above 1,000 engine rpm.
Ask around…you may find a good automotive electrician.

Honestly wouldn’t it just be easier to replace the alternator and the plugs. but then again I see why it may not be especially if the alternator and plugs are running right, plugs are gapped right and have no deposits on them. An added cost that might be able to be avoided. Come to think of it I should just replace the stupid thing. I have had problems the last couple of weeks starting the car in extreme cold weather. first time I had to jump the car. The last time, about 5 days ago, the car wouldn’t start at all. I have a 700 CCA battery. my other car is an 2003 Dodge stratus and it started right up with no help when it was -10F out. the Nissan on the other hand when it gets to around freezing it has a hard time starting. I didn’t think nothing of it until this last cold spell when it got really cold and the car wouldn’t start and it seemed like the car would kill the battery.

Changing expensive parts because you “suspect” that part is not a good troubleshooting tactic. So, you shouldn’t change the alternator until you’ve had it checked. The alternator needs to be checked for ac (alternating current) output to the car’s electrical system. Someone reported having an alternator which had an output of 25 volts ac. The voltage should only be dc (and no more than 14 1/2 vdc).
Auto parts stores will check the battery and alternator, at curbside, for free. Get that done, and regardless of what they may say to the contrary, have them to read for ac from the alternator. If they won’t, get the alternator checked for ac somewhere else. Let us know.

okay I understand. Just thought that maybe easiest. Just like in the older cars. I remember changing plugs, wires and distributor caps all at the same time just because it made sense to. So if I understand what you are saying if the alternator is putting out any kind of ac volts it is bad. If it isn’t putting out any ac volts but it is either below 12 and above 14 1/2 vdc then it needs to be replaced as well. As far as plugs go wouldn’t it make sense to replace them regardless. If I do replace them i put them in and don’t check for gap. In my owners manual the gap specs say .043 The plugs in the car are iridium tipped. I am so confused about plugs. In the past I remembered being told to double check the gap before you put the plugs in the car and regap them if the plugs need it. Almost everytime I bought and changed plugs in the past the plugs were never gapped right and had to be regapped.

You almost got it right. The alternator must output at least 13 1/2 volts dc in order to charger the battery. A lesser charge won’t recharge the battery. A charge voltage higher than 14 1/2 volts dc is too high (it will damage the battery and electronic components). A fully charged battery should hold 12 3/4 volts dc.
When the auto parts person gets your sparks plugs for you, the gap is set at the factory. Rarely, if ever, do they need to be re-gapped. I take a look at the gaps, and if they all look the same, I don’t mess with re-gapping.