I have been having a rough idle, engine knocking sound, bad gass mileage. on my 99 maxima (34k miles) for quite some time now. There is also less power, sometimes the check engine light stays constantly on other times it blinks(Seems to happen when I give it gas or go up a hill)

I took it to allens automotive on Hillsborough. They said there was a bad coil and they want to replace the spark plugs. They also said the dealer suggests replacing all 6 of them at the same time. The estimate they have for replacing the coils(6) and spark plugs is.

834.15 for coils (I am assuming 6)
$20 for spark plugs
$130 for labor

I just want to know if these prices sound reasonable or not.



On the print out they gave me it says the code was DTC P1320.



http://forums.maxima.org/showthread.php?t=451830.

I found this thread that says the guy was able to do it by himself and figure out which was the bad one by removing one at a time with the engine running.




Would anyone with some experience be willing to do this, if so let me know your rate.



Also if anyone could help me find a place to buy the coils cheaper that would be great. (Saw a few people on line saying they can get them for around $60 a piece)



If i can get them for can get all of them for around $300, it seems easy enough to replace all of them myself.

[Edited on March 26, 2007 at 4:10 PM. Reason : f]

3/26/2007 4:08:39 PM

stay FAR away from allen's.

sounds like you're on the right track as far as the problem.

[Edited on March 26, 2007 at 4:13 PM. Reason : .]

3/26/2007 4:11:11 PM

yeah im not going there again

its within walking distance so thats why I took it there

3/26/2007 4:21:42 PM

I would recommend doing it yourself as well. They aren't that difficult.

3/26/2007 5:44:21 PM

IT'S A 99 AND THE Coil PACKS ARE BAD? DAMN.

3/26/2007 6:10:27 PM

pull the coils, as you look at the connector with the clip facing up on the coil, the resistance between the right and center pin should be about 1M ohms, if the resistance is very low 0-100 ohms, then it is bad

and btw, my old boss at mission valley 66 was good friends with the guy that owns allen's and even he said they were sketch as hell

[Edited on March 26, 2007 at 7:02 PM. Reason : blah]

3/26/2007 7:01:37 PM

On my '93, they are fairly easy to take out. Unplug a wire, take out one or two screws, and then pull up on the coil. This is something you or anyone who has ever changed spark plugs could do.

The pricing sounds a little high to me. Advance sells them for the '92-'93 maximas for $80-$90. Coils for the other trim levels of that generation run for $50-$60 at Advance as well (one per engine).

Start at Advance Auto Parts. If you don't like that price, there are probably cheaper options online. Google "Maxima ignition coil" or something like that and autopartswarehouse and others will probably pop up. Sometimes those places can be cheaper, sometimes they're not.

Ask around on maxima.org for other ways to check the coils. The factory service manual for the '93 describes a test where you use a multimeter to check the resistance on the terminals. There's probably something similar for the '99s. Pulling the wires to the coils one at a time will tell you if one's not working at all though.


Or just listen to him ^. I type slowly.

[Edited on March 26, 2007 at 7:12 PM. Reason : :-]

3/26/2007 7:11:09 PM

Quote :

"btw, my old boss at mission valley 66 was good friends with the guy that owns allen's and even he said they were sketch as hell"

yep, that's who i heard alot of the stories from. they also have a number of complaints with the bbb.

my ex gf had a less than pleasant experience with them too. we got in a fight and i refused to work on her car, so she took it there and got taken for a ride, lol.

3/26/2007 7:20:27 PM

^^ yeah i found that multimeter testing thread on maxima.org but it all the graphs they had looked a little complicated and I didnt want to screw around with it not knowing what I was doing

[Edited on March 26, 2007 at 7:23 PM. Reason : f]

3/26/2007 7:23:26 PM

he had borrowed a lot of tommy's tools and shit over the years and then claimed they were his

3/26/2007 7:27:17 PM

^^ Could you send me a link to that? I'm curious, and I fail as an EE if I can't figure this out. My schedule's pretty messed up this semester, but I can probably help you out sometime if you want to check those that way. Most of the people who post in the Garage know cars a lot better that I do though, so someone else can probably diagnose your problem a lot faster than I can.

3/27/2007 3:02:07 AM

It turns out I have the Haynes manual for your car. It doesn't cover the engine in my '93 SE, but it does have an ignition coil check for '95 and later maximas (thru '99), which should be yours.

I can do this check for you sometime if you'd like.

Here's the procedure if someone else wants to try it. Looking in to the plug on the coil pack with the clip of the plug above the pins, the body of the coil above the pins, and the long part of the coil extending to the right, the pins are numbered 3 2 1 from left to right. Using an ohmeter, measure with the positive probe on pin 1 and the negative terminal on pin 2. This should read infinite. Switch the probes so the negaitve is on pin 1 and the positive is on pin 2. Haynes says this should be non-zero, but not infinite. The guys on maximas.org seem to be getting about 1.5k Ohms for this one. Haynes says to replace the coil if it fails either of those tests. Haynes also says to check from the contact inside the end of the coil (the one that touches the spark plug) to pin 1. This should read infinite resistance, and Haynes says replace if that fails as well.

The maxima.orgers seem to only check between the pins. Though that's consistent with the '93 service manual, they noted a couple problems with it. It didn't find the failure of coils that were definitely bad at idle (found by pulling plugs). Someone suggested that the pin measurements were just checking the primary coil. The Haynes test between the spark plug connecter and pin 1 might cover that; it certainly would involve the secondary coil (it sounds like an ignition coils is just a transformer, two physical coils of wire). One guy said you need to hook an oscilloscope up to check the voltage of the secondary coil, but even if you were to find a setup that could handle the voltage you'd still have to be Houdini to get a scope probe between the coil and the spark plug in the head with the engine running.

I think you should:
1) Pull wires one at a time with the engine idling. If you don't notice a change on a cylinders with that coil disconnected, that coil may be bad. Or it could be spark plug or maybe injector. This tells you that gas isn't burning in that cylinder though.
2) Pull the coils out. Look for cracks. If it's not insulated, the coil could be shorting to the engine head. Cracks may or may not be serious. I don't know, it depends on whether the coil is designed to use that casing to insulate it.
3) Run the resistance check. If a coil fails it, it is bad.

3/27/2007 4:07:46 AM

Yeah, I dont think taking a coilpack off with the engine running is a good idea.

3/27/2007 5:02:24 AM

* turn off engine between steps 1 and 2 above

3/27/2007 5:38:14 AM