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123 ignition problems

578 Views 19 Replies 8 Participants Last post by  Gubi
Hi everyone! first of all! Sorry for the long post! I'm hoping someone in this group can help me! I'm really about to give up.. So I bought the 123 Bluetooth version. it came with a programmed curve that was supposed to be the correct one for my 1983 spider, i had the bosch 0237002018 whit vacuum. So I put the engine at tdc.

Rectangle Audio equipment Engineering Electrical supply Auto part

Automotive tire Motor vehicle Vehicle Bicycle fork Gas

Motor vehicle Bicycle part Automotive tire Hood Crankset

Wood Tints and shades Font Automotive tire Pattern

if someone see something I have missed in these pictures please let me know!
So then I turn the 123 counterclockwise and the led goes on.. tighten everything down.. The cars starts, but runs quit bad, backfiring, slow on the crank.
I try to set the advance to the blue dot. 7degrees? doesn't work, car runs like a piece of crap.. after like 30 attempts doing the same procedure, following the instructions I realised that the rotor doesn't really point at nr 1 sparkplug wire, it's a little bit past the number one.. I have seen a lot of people having this issue, but haven't been able to sort it out, so maybe this is not the problem, although I really think it should be pointing at number one...

So I gave the the guy ho sold me the 123 a call, and he says, no I programmed it so you are supposed to light the led at the static advanced, not tdc.. Ok, so I put the engine at the blue dot get the led to lid up, (stil not pointing towards nr1) runs even vorse...

so I take a look at the curve that was programmed... looks a litte bit strange..

Slope Font Parallel Science Engineering

So I do some homework, and after a lot of reading I have programmed this curve and vacuum

Slope Rectangle Font Parallel Pattern

Font Slope Parallel Rectangle Pattern

So I uploaded the curves, got the green led to light at TDC, the cars fires up, and runs somewhat ok,but it's really getting late, so I dicided to continue the day after, getting the engine warm and and then set the timing.
Since that evening ,the car hasn't started..
No spark. thou i knew it wasn't the problem I bought a new ignition coil, bosch blue.. redone all the wiring and earhtpoints that has to do with the ignition and 123 distributor.. still dead.. did a reset of the 123.. no difference, tried to upload a new curve, still dead..

I can connect to it, the light goes to green on the distributor and it flashes green when I crank the engine, so it's not completely dead..

one thing that happend a few time while the engine was actually running, I couldn't turn it of whit the key, it just kept going... but I have checked the + side from the ignition like 100 times, when the key is turned of, there is no power in the cable. and I only have ignition + to the coil 15 the red from 123 connected to coil +15 the black from 123 to -1 on coil, the white tacho cable to -1 on the coil. The blue cable from the 123 goes to ground.

Does anyone have a clue to what's wrong? Have I got a bad 123 distributor?

Any ideas would be helpful!!!!




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Well, that's a weird one.

So the curve that you got pre-loaded is at least reasonable if you set the 123 up at the static mark (provided the static mark is at 6-7 BDTC or so). The second curve is the one I uploaded, and that will work if you set it up at TDC. So in both cases it doesn't seem like the curve is the issue.

The rotor pointing a bit beyond #1 I think is fine? I don't remember what mine looks like, but the spark is always going to fire BTDC anyway. Anyway, your current issue is no spark at all, apparently.

It sounds like you've got it wired up properly, but I don't get how it could have been running on if you definitely don't have power to the coil with the key off. Like, I might suspect a bad 123 unit, but even if the 123 were faulty the coil isn't going to spark with no power. So I still feel like you might have some sort of power issue there, but what it could be I dunno.

You've removed any ballast resistor and associated wiring, right? And the green/black ignition wire to coil positive just runs straight back to switched power at the fusebox? You're absolutely sure your blue wire has a good ground?
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Huh, how far is the rotor past the #1 wire? If it's completely past it that may be a problem. You are turning the body counterclockwise to just where the light first turns on, correct? This post has a photo of where it ended up on someone else's car:

Another thought: my memory is fuzzy, but I think there have been some issues where folks got the 123 with the drive installed 90 degrees off. I don't remember the details or resolution, though. Will it spark from the coil HT lead but not at the spark plug HT leads? That could happen if the rotor were too far off, I guess.

Also, you're absolutely sure you got the keyed distributor drive in the right way? You can force it in 180 degrees out if you try (Drew just posted that above while I was typing this). Theoretically the rotor should point to the front of the car at #1 TDC but don't trust that, actually verify the way the drive is offset in the engine and make sure it matches how you install the distributor. In my GTV, for example, someone installed the oil pump 180 out so that the rotor points rear when at TDC, this is not super uncommon.
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Found it: read the first post in this thread about the 123 drive being ~20 degrees off. That may be your problem? This is definitely not common, though.

Should be no issue if the 123 (appearance of the Led) is set to TDC? and the ignition wires are connected correctly?
If it's off by 90 or 180 degrees then it's no issue provided you put the plug wires in the right place. If it's off by like 45 degrees it would be a problem, because the rotor would be too far from any of the wires. The latter is what appears to have happened in that other thread.

Anyway, Tino, I mocked up your photos to show where the plug wires should be. If these are both taken at TDC and with proper distributor body location (i.e., the 123 has been turned counterclockwise until the LED just lights) then everything looks mostly right?

The 123 rotor is 90-ish degrees different from the Bosch, but the rotor is pointing forward at TDC and it's pointing to one of the plug wires. So as long as you put the plug wires in the right places (which, as Lokki pointed out, will be different than where they are with your Bosch) then I don't think you have a physical problem with the distributor or drive piece?

(Note: this all assumes I got the mockup right, and it's rather early and I haven't had my coffee yet so double check that)

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For curiosity: if thats the case the green light should not come on, right?
As this has to be tied to the #1 cyl position of the dizzy cap, which is tied by the groove in the dizzy housing so it has a fixed position?
You could be right? In thinking about it I think it would depend on how the light is triggered.

I'd need to really look at the innards of the 123 and think about it because my brain is failing me right now. The experience of that guy in the other thread suggests it matters, though, since he couldn't get it to work right until he moved the angle of the rotor relative to the drive.

Regardless, assuming the distributors in the photos Tino posted were timed right, and assuming I did my photoshop analysis right (big assumption on a Monday!) then the drive position is probably not the issue here, I think?
I don't know what if any long term affects you might encounter having your oil pump 90* or 180* out will have on the motor
It doesn't cause any problems provided you put the plug wires in the correct places and also match the distributor drive offset direction to the oil pump drive offset direction.

I you try, you can jam the distributor in with the key 180 degrees reversed and it'll run for a bit, but that will eventually break the oil pump.
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