MazdaManiac

iTrader: (3)

And, so? You mean relocate the car and the driver? I'm not sure what you are getting at.
The coil failure rate is probably in the 20% range or higher here.
That said, I went through two sets back in Maryland. The dealer there couldn't keep them on the parts shelf (that was before the revision and TSBs).

Delmeister

From your later post (Maryland), you are suggesting that these failures are not just due to the high Arizona temperatures. I called my dealer and he hasn't replaced any coils, but then again he hasn't serviced enough RX8s to make this a statistically significantly statement. Are these coils being replaced with those of original design, I mean is this VERY frequent replacement just going to continue?
So are you saying that if I want to operate my power windows, or my headlights, or seat warmers, or heater blower, or my rear window defroster, or something that say wants 15 amps at 12 volts I will need from 57 to 84 volts to drive it?

rotorocks

I think he talks specifically about the resistance on the coils. No?

MazdaManiac

iTrader: (3)

You have a little difficulty with Ohm's Law there, I see.
Try tweaking the "I" side of the equation, not the "E".
The voltage through the circuit remains the same, the current goes up.

cjwaggs

dude your avatars are the ****! And you really seem to know your stuff man.

MazdaManiac

iTrader: (3)

Just as an example, BTW, before you start spinning around and spitting.

If you have a power window circuit that consumes 15A (which is a LOT, but that was your example) and the resistance across ground is 3 ohms, you will see an additional 3.8A through the electrical path above the load demand.

two rotors

Actually what I was suggesting was to relocate the coils to a cooler place in the engine compartment(but you knew that),Rather like the 2nd gen RX7s(oh sh-t there I go again).
However now that you mention it maybe you could try Alaska

I checked other cars for coil failures and the only significant number was 25 coils for 2003-2004 Mazda 6.

Just as a matter of interest I checked our RX8 data for other failures and it can be summarised as follows:

No of cars:152
Engines replaced:1 HO 1 standard
Transmissions replaced:2 six speed man,1 4spd auto
Coils:4 on 1 car.
Clutches:3(plus 2 with the 6-speed gearboxes)
Catalytic converters:10
Sun visors:5 sets
Rear Lamps:12 sets
Heater control units:3
MOP:1

These are real data(I ordered most of the parts) and in some cases may be at variance with your experience.But it is what it is.

MazdaManiac

iTrader: (3)

You are also in Ontario.

Delmeister

It's been about a week now that I've been waiting for someone to comment on the nonsense that's been spoken here. But comments such as this
Really do mean that there is some confusion. There are two topics - the grounding kits and the coil failures. I was speaking about the grounding kits.

and this:
When complete rubbish can be viewed as 'knowing your stuff', there really is a serious lack of understanding. There is nothing wrong with this except that it might be phrased as "I don't really understand this so am not in a positon to comment..."

But first I would like to address this comment:
You might be appreciative of the fact that we have someone on the 'inside' that has made the effort to provide some real facts for a change. I know that facts can get in the way of theories sometimes. Furthermore, you initially implied that coil failure rates were independent of climate. Now you appear to say they do depend on climate. I guess you can't lose if you take on both sides of the argument.

dannobre

iTrader: (3)

Specifically which parts do you have a problem with?

I am in CANADA...and my coils have been replaced three times...the first time all 4, then just the leading( one quit completely) and I just replaced them myself again. Thats all in 90K km's......

Phil's 8

iTrader: (3)

This forum is a lesson on how to ask a question and then endear yourself to the people answering your question.

MazdaManiac

iTrader: (3)

I've learned fairly early on to give people just enough ammunition to shoot themselves in the foot and then get out.

TeamRX8

iTrader: (25)

including yourself ...

rotorocks

There is no confusion.
MM is arguing the point that grounding kit reduces the resistance. Does it not?

Lighten up a litle. Follow your own rule if you can not relate: Most of us find MMs avatars fascinatingly creative. We also think that he does know his stuff. Maybe not everything, as no one does, but enough to earn respect. MM contributed more to this community than anyone else (be that his expertize, or erotic content) and calling it rubbish (even if you disagree with it) is just not a very naiiice thing to do

two rotors

So are your coils actually failed(as in not producing a spark,other than the 1 leading coil coil you mentioned).

What shape were your wires in?The reason I ask is that we have changed about 6 sets of wires.

What did you use for replacements?The part no. currently used in the US is not available in Canada,although the part we get is actually the same part--it just costs about 4 times more.

Delmeister

Well spoken.

MazdaManiac

iTrader: (3)

Nah. Just you.
Don't you have a parking lot you need to drive around?

Delmeister

I am not having a problem with anything other than the usual (no start, moisture in taillight, dealer screwups etc.) Did I indicate somewhere that I was? I may have, I just don't remember.

Delmeister

To a request for evidence that grounding kits work:
Which was responded with
Followed by
Q: A device normally draws 15 amperes when placed under a potential of 12 volts. The negative terminal of said device is returned to a local ground (engine block, body panel, etc.). Under ideal conditions this ground is connected with zero electrical resistance to true ground (battery negative). If this local ground should be impeded from true ground by a 3 ohm resistance, what would the battery voltage have to be in order that said device operate at its normal ratings?

A: The circuit now includes the 3 ohm resistance which must also pass the 15 amp current. In order that 12 volts be dropped across said device, the battery voltage would have to be:
V = 12 + 15*3 = 12 + 45 = 57 volts
If that resistance were 6 ohms, then the voltage would have to be 102 volts.

Since the battery voltage is what it is, the question could be phrased differently.
Q: Given the above situation with the faulty ground, what voltage would be developed across said device?
A: The effective resistance of the device is V/I = 12/15 = 0.8 ohms. With a 3 ohm resistor in series with the device, the voltage drop across the device becomes:
V=12*(0.8/(3+0.8)) = 12*0.211 = 2.53. The current would be 12/3.8 = 3.16 amps
For a 6 ohm resistor, the voltage across said device would be 1.41 volts, the current 1.76 amps.

The car would probably not run with resistances this high provided you could even get it started. On a very cold winter morning where I live, the starter probably draws more than a couple hundred amps while the battery voltage probably drops to the vicinity of 8 volts. Figure out how much starting voltage would actually be needed if the resistance between the engine block and the battery negative were even as low as 0.1 ohm.

Delmeister

I believe you mean 4 amps (12/3), if I understand what you are saying, which is that the 3 ohm resistor goes in parallel with the load. If this is in fact what you are saying, then I truly do not understand why you believe that.

About the window. Some time ago I did a test because I was curious to know what happened when the power window button was held down after the window had reached the end of its travel. I rigged a 20 amp full scale analog ammeter in series with the window wiring. Here is what happened.

On pushing the button, there was a large instantaneous pulse of current (expected). The current attained a steady state of something less than 10 amps (can’t remember exactly) during window movement. When the window reached the end of its travel, the current suddenly shot up to the upper part of the scale (in the area of 15 amps, again cannot remember exactly). I kept holding the button down for an additional 8-10 seconds. The current kept flowing. I had expected a current cutoff before then.

For what its worth, I can tell you the sunroof does not operate that way. The current cuts off as soon as it reaches the end of its travel. I cannot remember how much current it drew, nor did I test to see what would happen if I tried to impede its movement.

kinchu007

iTrader: (1)

This is a fun read!

You guys are way beyond me when it comes to E&M (I was never too gifted at physics), but from my toying around with car audio 3 to 6 ohms sounds like a lot of resistance.

Maybe this was already posted, but what are the exact symptoms of coil pack failure? Ever since my track day when the car ran super hot and spilled collant all over my K&N and my car started running so clean I can almost eat off the inside of the exhaust tips, I'm pretty much paranoid about anything being broken.

otakurx

3ohms is not that much resistance, think about it an LED tends to like a 1k ohm resister before it. Now when talking about capacitance ferrets(sp?); 3 ferrets(sp?) is a decent amount and could kill you if discharged into your body.

dannobre

iTrader: (3)

Farad?

Jon316G

iTrader: (1)

^^ Its actually farad... now that we got that cleared, back to the topic. I'm loving this thread (heck, this makes the workday go by).

california style

i like the idea of killer ferrets though, then things could get really interesting!