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99 FLHTCUI Magneti EFI to carb conversion

I have a 99 FLHTCUI I’m having multiple problems with; dead tach, backfiring, low idle, choking off, code i can’t pull through the on / off method, etc, likely all related to the ECM. I’ve replaced the crank position sensor, traced wires, tightened everything I could, cleaned the pins in the ECM, replaced the tach, no luck at all. Had a mechanic look it over, couldn’t find anything. So he increased the idle so I can at least ride it some but I’m scared to go too far.
So I read a little about converting to carb, saw there are some kits available, saw others had complete parts lists, but also read there are some quirks specific to that year that have to be specifically addressed, and I read conflicting things. Also I’m not certain what all else might be left off and not working after that, like anything that is electronically powered through the ECM, like the tach for one.

Just throwing it out there to see if anyone has specific experience with this models conversion. Before I dive into it I’d like to be as informed as I can. I’m no mechanic but I can do some things and figure things out to a point, and I understand that this project isn’t really that hard to DIY. It can’t be any worse than chasing rabbits trying to figure out what’s wrong with the electronics in an EFI Ultra classic



Thanks, I’ve seen those before, I’ve looked all over and about had my mind made up to do it, but try to do it as budgetarily responsible as I could; looking for individual parts here and there for the best deals. So I copied some basic parts lists with prices somebody threw out there about 5 years ago. Of course the prices now are about 25% higher and some of the places they came from are gone. Gonna be probably $400-$500 before I even get a carb, then to decide between Mikuni HSR 45 and S&S E.
Then I go by my buddies shop, he has a 02 samebike, but Delphi instead of MM. says except for his choppers, he’d never switch back to carbs, been building and riding for 40 years. Said he thought I should try a thunder max ECM. But in the long haul I think the carb conversion would be more reliable .

Yeah, Harley dumped the MM in favor of the Delphi. If it was up to me, I'd update to the Delphi but carbs are easier for self maintenance if something does go wrong. EFI is more efficient and smoother but more complicated. Either way, it's going to cost you. You could look for a used set up from a salvage yard. Don't forget that the electrical system will need changes.
Some good info to consider.

Yes, I’ve looked at all the options I think, and since I’m not a mechanic by any stretch, I can learn and do some mechanical work, but electronics boggle my mind. When I printed the wiring diagram for mine to figure out where all the wires to the tach went, I had like 5 pages of printout and my mind was blown. I figured out where the wiring went, found the one going to the ECM but it was okay.
I just figure in the long run I stand a better chance of being able to keep it on the road, and doing more of the work myself. The costs are all a minimum of $800 if I’m able to do it all myself and with my buddy’s help. Just tired of chasing rabbits every other week it seems. Thanks for all your help.

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