I post this here in case it's happened to anybody else.

I was out practicing some slalom work with Alex and lourx8 this saturday. While driving my car around I noticed at some point there was a strong burning electronics smell. At the time I assumed it was just rubber, sicne the AC was running on a warm day, but now yesterday afternoon afterwards and this morning I have noticed that the car has almost no power below 4000RPM, and then the usual power above it. I disabled the stage1 and it's exactly the same. I'll pull the stage1 out tomorrow morning as I need to drive a bit still and the hardware for mounting the ECU properly is about 50 miles from me.

Has anybody else had this happen? Just to clarify there is no CEL lights, no warnings or anything like that. It's not like the switch on the stage1 was bad or such. Car just has no power down low. As an example at 40MPH in 6th gear, flooring it takes about 30 seconds to get to 50MPH.

posted by emailists:

Installed my CZ 1.1 unit tonight. My car has not been flashed- manufacture date was dec 3 2003.

ANyway I thought I would try it out before I get the M flash this week (hopefully). I was sure to run it longer than 15 minutes.

funny thing was I couldnt get the DSC to reset by turning R&L. Once warmed up and restarted the car, DSC light went off.

It felt really bad below 6K , and only a litttle better beyond it.
just no low rpm power, and it felt like it was going to stall going into 1st from a standstill ( I needed to rev higher than usual).
Maybe just my imagination, but the car sounder different too.

ANyway, after about 30 mins of driving, I turned the CZ unit off, and took it for a 15 minute spin. The upper RPM was much better (back to normal) but lower rpm was not back to normal. (though didn't seem as bad as with CZ turned on)

Could I have installed something wrong? (only thing is plugging in wrong connector and i dont think that is possible).

I am reserving judgmenet of course for when I get my M flash- I think I'm going to remove the whole unit due to the "Internal Failure thread" someone experienced with M flash and CZ unit installed and turned off.

Tomorrow I'm going to remove it completely ( till I get the flash)

Any clues as to why I getting this strange performance?

similar? maybe

I got my "M" flash last Friday (or so I believe; the dealer claimed to have updated the ECU).

Since then I've smelled the same burning rubber smell when I drive it.

Power is good. No performance problems. Just the weird smell making me a little nervous.

Dan

emailists problem sounds a lot like my own. The odd thing is I have been running this setup for at least a month with no problems.

I am going to check the map loaded in the stage1 now and if that looks OK I am removing it so I can take the car in for service.

As an update, I checked the stage1 and the map showed up correctly. Checked the wire harness and didnt see anything burnt on it or in the case. Since removing it the car still feels a little week, but it seems to be getting better. Only got to drive 20 minutes or so though so later tonight I'll take it for an extended spin.

With Mazdamaniacs help I have seen that indeed I have at least 1 burnt coil, possibly 2. I'll let Maurice know.

Genom what do you mean burnt coil? Cause I think I have the same setup as you but never experienced a burnt smell and no loss of power. Please elaborate, thanks

If you look under the corrugated tube that goes from the airbox to the throttle body you can see 4 units lined up. These are the ignition coils and are in charge of sending the signal to the spark plugs if I understand correctly. Look at the pic Maniac posted in the toehr thread and you'll recognize them. If you look at them from the driver side of the car you can see the top of the connector that Maniac describes and seeing the 4 side by side, it's pretty obvious to spot the ones that have melted. If you havent lost power, then your fine. Rememebr that this is not a new stage1 install. this was a setup that ran for over a month with alot of driving. it wasnt until I bused the car on a hot day that I had a problem. Bfre that it's been great.

GENOM no matter how you drove the car the stage 1 is not suppose to burn your coils its a performance mod. how else are you suppose to drive it .it may be the stage 1 was not working right .i heard other people had problems too but maurice fixed it.let us know how you make out.

This doesn't sound stage 1 related at all.

Why not? It's controlling the coils, and before the adapter board was figured out it would burn coils up. Maybe there's something that needs to look at as a long term thing.

it probably is related to the tuning, i remember CZ and mazdamaniac both burning out coils when they were tuning.. You're right, it IS a performance mod which means that you are potentially running a slight bit more "dangerously" than stock.

Performance typically comes at a loss to reliability. This does not mean that the CZ unit is bad, it's just that the map might be a little too agressive in "our" (central/south florida) enviornment. I for one don't mind having to change out 2 $60 parts once in a while if it makes my car run a little better. As long as it doesn't happen every week.

Originally posted by smrx8
GENOM no matter how you drove the car the stage 1 is not suppose to burn your coils its a performance mod. how else are you suppose to drive it .it may be the stage 1 was not working right .i heard other people had problems too but maurice fixed it.let us know how you make out.

yikes, burnt coiks w/ stage 1. a question for you guys I am seriously considering buying stage 2 but that might even pose a greater danger than stage 1 to the above referenced. why is it that you rarely hear about anyone buying stage 2 when it is so much of a better deal for the $? Is it the fear many have of burning the clutch or what?

Just for clarification I looked at my coils today and I couldn't see anything. Do you actually have to pull it apart to see if there is any damage or would be able to see it right away. And if you do have to take it apart, is it easy to do and any instructions?

Could be you just have defective coil packs. But it could also be the CZ unit.

The Stage 1 is basically a Greddy eManage that has a custom CanZoomer Stage 1 map for the RX-8. I believe the problem is that the eManage does not let the voltage to the coil packs drop to zero Volts in between charge/discharge cycles as they expect and need, so they heat up. 99% of the time they can handle this and not overheat, but you may be in the 1% that cannot.

Last I heard, Maurice is working on a fix.

Maurice will take a look at my unit and see if maybe the putput is to high or otherwise borked. I'm not too worried about it though. If it was slightly bad coil packs, the poroblem has been fixed, and if it's a recurring thing, then it will be time to work out something else. But I aint gonna worry about it until it is.

Thanks, please keep us abreast of the situation as you get more information. I'm in the same boat as you, although I have not experienced that problem. I have noticed some preformance degredation as I take long drives in the heat.. I have not yet blown my coil packs.

Originally posted by Genom
Maurice will take a look at my unit and see if maybe the putput is to high or otherwise borked. I'm not too worried about it though. If it was slightly bad coil packs, the poroblem has been fixed, and if it's a recurring thing, then it will be time to work out something else. But I aint gonna worry about it until it is.

i took a long trip today and smelled something funky like electronics burning and I don't have the CZ mod... i didn't notice any performance loss though and i thought maybe it was just highway traffic fumes. I guess i will see what happens in the future.

I've been watching this and keeping quiet as I have no definitive facts to put forward yet, however, I have a theory as to what is happening. I will be doing more measurements soon (waiting for a scopemeter to arrive).

The coil packs consist of a smallish coil and a power transistor. The power transistor grounds the coil primary. The other side of the primary is connected to a resistor and then to +12V, both in the wiring of the car. The PCM sends out a +5V 5mS pulse to the base of the power transistor to turn it on. The power transistor draws enough current in the base to load that down to +3V.

I think there are two potential problems with this setup (no pun intended ;). Unlike most current logic chips, the voltage that the PCM puts out goes from 0V to +5V. Most logic puts out +1.4V or so when "OFF" to +4.4V or so when "ON". This is what our box puts out, so we had to add a series diode to the ignition output of our unit, as 1.4V will keep the transistor somewhat on and heat it up. That is what happened to Maurice's coil packs and Maniacs as well. The diode drops the voltage by 1V or so. The transistor doesn't start to conduct until the base voltage reaches 0.7V or so. Problem one solved.
Problem two is transistors loose "current gain" when they get hot. The PCM only puts out so much current (hence the +5V drops to +3). If you don't drive the coil transistor to full saturation (minimum voltage drop across it) it will dissipate more than normal saturated power. Think of it this way (for those without electronic experience). The +12V flows through the resistor (causing a voltage drop across it and limiting the ultimate current through the coil), through the coil (causing a voltage drop across it and charging up its' magnetic field - inductance), and through the power transistor (which will have a small voltage drop across it when saturated). Each component will dissipate heat based on the voltage drop times the current. This heating will cause loss of current gain taking the transistor out of saturation if it is too much. This will generate more heat which will further drop the current gain in the transistor which will further increase the voltage drop across the transistor. It's a classic thermal runaway situation.
So, if you operate the car in such a manner that heat builds up in the engine compartment you will get closer to triggering this scenario.

I will be doing measurements to confirm this, and if this is the correct analysis, we have a cure and will let you know. Our box actually puts out more current than the stock PCM, so this should be solvable with it. More current will keep the power transistor in saturation at higher temps.

Just to finish the ignition phase, when the 5V 5mS pulse ends the power transistor turns off and the coil field collapses, causing the ignition spark.

Oh, and I doubt you will smell this happening. First, it's in the engine compartment and you don't get smells from there too easily (or you would be gassed by all the smells the engine generates). Second, all that happens to the coil pack is the heat causes the casting compound to swell. It doesn't actually burn.

I wonder if we can have a company like MSD build some remote coils.
They would no doubt be stronger and if they are mounted somewhere(anywhere) off the engine, surely the heat would be reduced.

Now that's a thought! Anyone have any contacts with companies like MSD?

I have had this similar situation happen once. I wasn't even driving it hard. I took a left turn when the light turned green and after shifting to 3rd, I smell an awful burning smell. I immediately pulled over with my emergency lights on. I inspected the engine bay but I could not smell it anymore. I have thought it was the car I was following. I should check my coils tomorrow then.

Also, ever since that, I have not noticed any problems with how my car is running. I dunno, maybe I'm just not noticing "it" yet. Yikes.

rx8friend: Lets just say I can smell a burning IC a long way off :D

I'll be shipping my stage1 back to Maurice tomorrow for him to check it out.

Er, is this more likely from sitting in traffic or driving like you stole it? Or cruising at 75 mph? Serious question.

Originally posted by RX-8 friend
So, if you operate the car in such a manner that heat builds up in the engine compartment you will get closer to triggering this scenario.

same question as shebam. also just a thought. I wonder if the engine cover is restricting any air flow?
I also wrote on another thread about heat concerns (i live in georgia) and the cz unit. I have the 1.1 and have been running it about 2 wks. No problems and it has been around 93 degrees, but I am a conservative driver and I haven't taken any long trips. I also wonder about the heat and the unit itself. Its pretty tight in the ecu box.
errrr maybel , I need to stop wondering and just drive my car LOL!
Im sure cz will address these issues but lets keep this thread going.

I havent run an engine cover for the past 3 or 4 months, so that wasnt it in my case. I think it was just my coils where gonna go eventually. I doubt the stage1 casued anyting, unless one of the components on the extra circuit for the ignition control is bad or defective. Maurice will test that out to make sure it's OK or not as the case may be.

Better put your engine cover back on. It's supposed to improve air flow under the hood. Directs it out the side vents, I'm told.

Worst case for high underhood temps - high load slow speed - such as autocross. High speed will not heat it up as there is lots of natural airflow at high speeds. Pull off a highway and drive slowly up a steep hill - that'll heat it up! Heat soak is caused by the engine operating heat normally removed by the cooling system staying in the engine because you came off the expressway and stopped the engine without letting it cool down for a few minutes. Check out cars parked in rest stops on highways. You'll find at least one in twenty has boiled out a bit of coolant.

Of course none of this will damage the coils if the engine is shut off.

Thanks. But now I'm tempted: "So, officer, I HAD to take my front plate off to improve air flow. Yes, I'll put it back on in less stressful driving conditions. You don't give a WHAT?"

Originally posted by RX-8 friend
I think there are two potential problems with this setup (no pun intended ;). Unlike most current logic chips, the voltage that the PCM puts out goes from 0V to +5V. Most logic puts out +1.4V or so when "OFF" to +4.4V or so when "ON". This is what our box puts out, so we had to add a series diode to the ignition output of our unit, as 1.4V will keep the transistor somewhat on and heat it up. That is what happened to Maurice's coil packs and Maniacs as well. The diode drops the voltage by 1V or so. The transistor doesn't start to conduct until the base voltage reaches 0.7V or so. Problem one solved.


Maybe not. A single diode (Silicon) is good for, IIRC, a .7V drop, leaving you a potential .7V signal, which could cause a leak in the power transistor (gain mode vs saturation mode). I seem to recall that this is what Open Collector drivers are for.... OC will "shut off" the output driver transistor in the IC and you have an external pull-down resistor to ground to take the leakage current ground. You can still have a bit of voltage present (leakage current across the resistor), but you get to manage it better.
Or maybe just a second diode?

No, common misconception - a single diode will drop 0.7V with very low current (about 1mA or less). Check out a data sheet. Under normal operating current you will find about 1V drop. Measured it. Got about 1V. Tried two diodes, got a 2V drop and started having problems with Maurice's car (which causes me to think it's not saturating the transistor when "ON"). Switched back to one diode, problem solved. We looked at "digital transistors" too. Unfortunalty they invert the output so you need two. They take the output down to about 0.2V. Parts count went way up (regulator needed as well as the two devices plus some resistors). More parts to fail. If we can't make the diode reliable we may have to go that route, but current indications are one diode will be fine, in fact better than stock, as the electronics we are using can drive more current than the stock PCM.

Now, in truth the current units that have been shipped also had a resistor to ground to lower the drive current. We thought being closer to stock values was better. I now think those resistors should be removed (two 2K2 resistors on end of board - they can just be cut of - leave the 10K resistors alone - they are part of the tach output). This is on the small PCB beside the Main unit. Just incase any of you want to experiment.

As I said, more measurements will be done soon (with a heat gun and scopemeter).

Here's a stupid questiion: Does the grounding kit offer any aid for this problem?