512 BBi ignition problems

First the car quit completely while running at 60 mph. I found a dead cell in my battery and replaced the battery. It was backfiring and one bank was running richer than the other. When I replaced the battery, the car ran great, just like it was supposed to. The alternator is putting out 13.86 volts. That euphoria did not last long...again, with a full battery charge, the car started backfiring and acting like it had no power. I have checked the fuel pump fuses (actually had fuel pumps repaired/replaced recently) as well as having one FD cleaned...it was a mess. I think it is the digiplex... but am not sure....should i check the output of the digiplex and how do I do that? Help someone. I have no mechanics near me that are not afraid of Ferraris and I am tired of hauling cars 120 miles to nearby cities and having someone give me crappy service for lots of money. Thanks.

just checking to see if I have been unsuspended

After disconnecting the battery, I would disconnect the connection to the digiplex and clean the terminals...both sides. Reconnect the digiplex, then the battery, and check it out. Could be just a loose connection.

Coach,

It very likely is the Digiplex. The only foolproof method I know of checking them is to plug in a Known Good Unit to see if the problem disappears.

Maybe one of the other guys here knows a different trick?

If it turns out to be the Digiplex you have 3 options, a new one, a Perma-Tune unit they install in your original Digiplex Outer Housing, retaining Stock wiring & appearance, or an MSD Mod.

http://www.permatune.com/Products/Fe...ari%201512.htm

Regards, JRV

I have AEC 104 I believe on my daytonas...but there are two of them, so I cannot use one from there because they control 6 cylinders ignition wise ( I actually don't have them connected..they make too much noise and they don't make the car run any better). But the point that this module needs to be tuned to 12 cylinders...right?

Coach,

The Boxers use the AEC104B-660, not sure if the Daytona unit can be swapped but if the Daytona unit has a 12 cylinder function and the same 6 wire plug it may work.

One thing about the Boxers and the Digiplexs in particular, when they have erratic running problems and it can't be traced to the Fuel Pump fuses it is almost certianly a Digiplex going bad, and truly they don't seem to need a reason to pack up & fail.

JRV

JRV, I did some checking. The daytona units which were not the original ones were actually AEC-104 BW and they are identical in size to the AEC 104B-660 which is on the boxer. They have the same 6 wire plug and it appears that 660 limiter can simply be taken off the boxer unit and screwed into the daytona unit...not sure as I have not taken the boxer unit off yet. It seems that with that 660 limiter attached on (?) they are the same unit...any ideas out there?

CoaachI,

I suppose if you're not using them on the Daytona anyway,...then there is nothin to lose, might as plug it in and try it. It will either start or it won't. The one question in my mind though, although I'm very curious to know if they will crossover, is that if it runs poorly on the Daytona unit I don't think it proves the Boxer Unit is good of course if you swap and it does run well again, then it does prove the Boxer unit is bad. .


Regards, JRV

Coach,

As best as I can remember, the ignition units themselves are very, very similar, model to model...The big difference between units was only the plug-in rev limiting module. Although I'm not using the Digiplex on my BB anymore, the model number is AEC 104BK...also with a six wire plug.

Personally, I'd give it a shot...

Regards,
David

Thanks JRV and David. I am planning to tackle the project today/tomorrow. Take out the Dixiplex, unplug the rev limiter, plug it into the daytona one and see what happens. I have two daytona dixiplexes which I bought some time ago, installed them, didn't like the hissing and disconnected them. The daytona runs great without them, though I have thought about some more modern replacements such as MSD units for the daytonas. Any opinions there...do these things actually work? Daytonas (2 of them) run great with these units not wired in.