260z stalls at idle after warm up. Carbs?

[Rill Cosby]

If it's on its way out, I think you might be able to use an HEI as a replacement.

Pardon my ignorance on this. I did some research and I'm still at a loss on what I exactly need or could use in a replacement for that part. The unit number on the transistor box is E12-05. I've only found one site that may have that part.

[SteveJ]

The HEI would replace the transistor box. You would wire it near the distributor, going to the pickup at the reluctor and to the coil. It's at least an order of magnitude cheaper than the transistor box, too.

You would use a writeup for a 280Z, like this one: hei. Here's another one: GM HEI retrofit

Here's another: Turbo Ignitor Swap / Upgrade - Chevy HEI - ZDriver.com. Log in at ZDriver.com to see the pictures.

Edited September 18, 2013 by SteveJ

[Rill Cosby]

I hate to have everything spelled out for me but I'm going to need it. So what you are saying is the quickest and cheapest method would be the HEI 4-pin module way? I should be able to go to the local auto parts store and pick up a HEI 4-pin ignition module, like the one in the Chevy HEI link you posted, pull out the old transistor module and wire in the new ignition module? What I'm gathering from the other links is that I would also need a different type of distributor than what I have now to run the new module.

By the way, thanks for the patience and all of your help, and everyone else's input. I definitely owe you a beer or two!

[SteveJ]

I hate to have everything spelled out for me but I'm going to need it. So what you are saying is the quickest and cheapest method would be the HEI 4-pin module way? I should be able to go to the local auto parts store and pick up a HEI 4-pin ignition module, like the one in the Chevy HEI link you posted, pull out the old transistor module and wire in the new ignition module?

It would be quicker than to find a working 260Z box.

What I'm gathering from the other links is that I would also need a different type of distributor than what I have now to run the new module.

That's not the way I understand it. The 260Z distributor is similar to the 280Z distributor in that it has the reluctor and pickup. Some of the old writeups on 280Zs and 240Zs do not always accurately capture what aspects of the 260Z are similar to which car. I selected the 280Z links on purpose. The HEI is a cheaper route than the 280ZX distributor. For the ZX conversion, you need the distributor and the mount. For this one, I believe you only need the HEI. Even if you do need the 280Z distributor, you could swap that in and not have to change the mount.

[Captain Obvious]

Good pics. I don't see anything that screams obvious problem. Two things catch my eye. First is a couple missing clamps on things like the brake booster and PCV vacuum lines. Not the cause of your problem, but might be providing a little vacuum leak. Second thing is what's with the hole in the middle of the EGR mounting casting. It's not sucking air through that little hole in the center, is it?

As for potential heat related ignition issues, before you drop time or $$ on a different system, you could shoot a hot hair dryer at your existing module to try to recreate the problem. And buy a $5 can of circuit cooler at Radio shack to cool it off and see if the problem goes away.

[Rill Cosby]

Good pics. I don't see anything that screams obvious problem. Two things catch my eye. First is a couple missing clamps on things like the brake booster and PCV vacuum lines. Not the cause of your problem, but might be providing a little vacuum leak. Second thing is what's with the hole in the middle of the EGR mounting casting. It's not sucking air through that little hole in the center, is it?.

I plan on going through new hoses and clamps, hopefully sooner rather than later. The hole in the middle of the EGR mounting casting isn't pulling in any air.

[Rill Cosby]

It has clearly became a overheating issue in the ignition module. Now the only problem I have is identifying is if the ignition module itself is bad or something external is causing it to overheat. I found a "never been used" ignition module with the same serial number and plug so I decided to go that route first. The cost was about double the HEI replacement but I would don't mind paying a little extra for a direct plug in and ease of mind of proper installation. That way if I experience any overheating afterwards I can narrow it down to the problem hopefully being something external.

I'll definitely report back once the part comes in after a couple of days.

[Captain Obvious]

Glad that you were able to narrow the problem. That makes things much easier.

Thinking out loud, the only "external" thing I got that would put extra heat into the ignition module would be the lack of a ballast resistor where one is required. Maybe the PO didn't get it hooked up right and/or shorted it out somehow? Without the ballast resistor, you run the risk of pulling too much current through the ignition coil, and that might be enough to mess with the ignition module. I've not seen it, but I guess it's possible.

Just to be prudent, you should check your coil and ballast connections carefully and make sure everything is done correctly.

[SteveJ]

Corrosion in the box could cause hot spots.

[Rill Cosby]

Sorry for getting back so late to this topic, I've been so busy lately since the car has been running and haven't really had access to another computer. I just want to clarify some things, just for future reference, if someone stumbles upon this thread. The problem did seem to be the ignition module. The car has been running fine since the new one was installed.

I wanted to post some picture of the old, stock ignition module and the new one that I picked up.

This is a picture of the old, stock ignition module. Almost like a soft aluminum casing that has a heat sink style to it. The number on it reading E12-05.

Then a picture of the new one. I was aware the numbers didn't match up exactly, or I should say the extra letter didn't, on this one but the plug matched up and I was that desperate. Crossed my fingers and hoped for the best. The new one reading E12-05K. It's been installed and running fine since. The outer casing is completely different and so are the internals but I just figured they might all do the same job in the end. Hopefully it performs well in the long term. Sorry for the blurry picture.

All in all, thanks for all the help guys. It would have been a long road trying to figure it out without you guys. I'll definitely be back again haha.

[SteveJ]

It would be interesting to crack open the case and identify the transistors and circuitry in it, too.

[Captain Obvious]

I believe they switched from the finned aluminum cover to the black painted steel case on the 260 to 280 changeover. The 260 used the finned aluminum and the 280 used the black painted modules.

So, you were thinking that your original module was getting way to hot... Does the new replacement get hot too, or has swapping the module taken care of that issue?

It would be interesting to crack open the case and identify the transistors and circuitry in it, too.

I popped the cover off the 280 style a while back. Exactly what you would expect... Lots of mid-seventies discrete electronics. With the easily obtainable alternatives (like ZX or GM HEI) I wasn't interested enough to do any reverse engineering. Interested enough just to peek around, but didn't trace anything.