New owner with first problem.

only through the connector...that's why you can swap the connectors between the two modules without moving any other primary or secondary wires.

The module is mounted to the top of the coil only for heat sinking. Even ground for the module is via a connector wire, so you can plug a module into the connector and leave the module hanging in the air and the car will run...at least until the module gets too hot and starts misbehaving - or worse, burning up.

yes and no. Heat sink compound (sometimes called thermal paste) is just some material that transfers heat well, and it's thinly applied to just fill in any voids between two surfaces. It sometimes has some non-corrosive additives, and isn't necessarily conductive....depends on what it's made of. Here's a page that says it way better than I can:
http://www.heatsink-guide.com/content.php?content=compound.shtml

On my '89 329, there was a bead of some silicone-like material around the edge of the module to keep water out, and the heat sink compound was just on the metal portion of the bottom of the module.

standard white heat sink compound (silicone with zinc oxide as the heat xfer ingredient) will work fine. The "arctic silver" stuff I mentioned contains silver as well, and is more efficient. It's overkill for the module, but as I had it, I used it.

I assume the usual suspects like t-rutlands, ricambi, maranello parts, etc would have the module. I got mine from GT car parts (623-780-2200) for $96. Part number 124273M - which is probably not an official ferrari number, as ferrari did not originally sell the module separately from the coil, and 124273 is the entire coil+module.

if you just ask for a 328 ignition coil module, they'll know what you want. If you get a price above $500, they are quoting the entire coil+module.

Then just ask 'em if they have the heat sink compound. If not, even places like best buy are possible. Any store that sells aftermarket cooling fans/heatsinks for pc's will have it. The basic white stuff is around $3, and the premium stuff around $7.

 

I ordered what I thought was a module and coil from GT and was quoted a figure of $348. I bet I am getting a coil and not a module too. Should be here today, so will post when I find out...I've been following this thread since this seems to be a 328 problem that can strand you somewhere. I was going to buy a spare module and coil just in case and carry the tools to install it. I got spooked when a bank went out after my first few days of ownership and after a week of feeling sick, I luckily noticed a disconnected coil wire. I really want to continue #73231 as a car that can be driven on long trips with confidence. Do people just buy 2 coils and modules and keep the old ones for spares? Are these things a weak part? I don't want to waste money, but what do other prudent 328 drivers do? Thanks Paul

 

there's lots of possibilities. If the module goes south, it can draw excessive current through the coil and heat everything up. If the coil primary resistance drops, you'd get more current flow and heat from that too. If there is a problem on the secondary side (bad coil wire, rotor, plug wire or even a plug), the high voltage surge generated in the coil has to go someplace, and through the module is one possibility.

you could compare the resistances of the primary and secondary windings on the coil. I don't have the numbers handy, but the primary is very low (like a couple ohms or less). If can be a bit of a pain to get the plugs off the primary connectors...lots easier if you dismount the coil bracket from the frame so you can get better access.

anyway, pop in a new module and see if you still have one coil/module getting a lot hotter than the other. If you do, swap the coils piecewise, testing between each step to see if the hot coil changes:
1] swap just the module connectors between the two modules
2] swap just the yellow primary wire plugs between the two coils
3] swap the non yellow-primary wire plugs AND the secondary/coil wires between the two coils.

If after all that, the same coil is getting a lot hotter, it's gotta be the coil.

the coils seem to be pretty solid, so having a spare is probably overkill. A spare module couldn't hurt, I guess, and it's small. Personally, I just go with AAA and a cell phone, but I do most of my driving where a cell phone works, and there's a casino within a couple hundred miles so there's something to do while waiting for fedex to show up with the spares that I didn't have the foresight to stock up on

wrt reliability, I've put about 20K miles on my 328, and the only significant failure (that I didn't cause myself) was the A/C hose blowing out due to the hole that gets worn in it where it loops up over the gas tank. That was only significant because it was about 110 degrees F outside at the time. Needless to say, I headed straight for vegas under the impression that my luck could only improve. I'm blaming the results on sunstroke, though I suppose in hindsight it may have been more sensible to replace the 10 gallons of sweat I lost with water instead of scotch.

 

Hi,...my package came from GT Car Parts...124373...Coil AND module for $348....Total with UPS was $361. Wolftalk, thank you for your information.
I figure that I have bought insurance that neither will go bad...they seem to know when you have a spare and keep working. Paul

 

At Harbor Freight they had an item that I used to have when testing old MGA's, and the like. It is called the "In-line Ignition Spark Checker" #04424. All you do is unplug any spark plug wire, plug the checker onto the spark plug, put the other end into the engines plug wire. Crank...if it flashes...you are getting spark. Darkness....like Lucas electrics on the MG...no spark. I haven't seen these for years....For a whole 6 bucks, what a deal. Paul

 

Ty,

For what it's worth, Autozone has the ability to "test" these modules - I can't remember the module # in their book but it's in a black plasstic box stored in the alternator test bench. I took both of mine there a few years ago, they have a schematic to attach tester wires (we just matched configuration, not "Ferrari") and both of mine lit the green "good" light. They also sell replacements (I never purchased so not sure how well they would work on a 328) that I have listed as NAPA #RB100 or TP100.

Best,

Carl

 

one you fix up an ignition problem, ya gotta check the plugs to see if they are fouled. If plugs are ok, a good italian tune-up helps to burn up stuff due to the misfiring cylinders.

if you don't want the bad module, send me a pm. I'd be interested in doing some characterization work on it once I get hold of a scope to see what it's doing.

did you try the autozone test on the bad one? I tried that, but the person at AZ that day wasn't able to figure out what to do. There's a few different modules in that form factor, but it's not likely that testing it using any of the parameters would hurt it.

coil and module for $348? That's only 2x what a similar part would cost for a higher production car...a bargain by ferrari standards