More fun with MM!

[dunbarton]

Seeking advice from those who know MM, up close and personal... LOL.
2000 FLHTCUi now with 100K of relatively trouble-free riding. Only engine mods are 21G cams, hi-flow a/c (clean) and V&H ovals.
Over the last few years it has had the typical full warm engine low idle problems but not so serious I just lived with it because the bike worked fine in all other respects.
This year it's fuel mileage has dropped @ 10-15% and it's delivering about 180 miles (300 km) on a tank where in past 325-350 was usual. I pulled the plugs.. dry black soot @ the base and electrodes are perfectly clean with no deposits of any sort. Leads me to suspect too rich mixture. Tried both oem HD and Champ RA8HC. This doesn't look like oil. In itself, this isn't a show-stopper but when coupled with the low-idle they may be related. No codes, current or stored.
Bike doesn't smoke, no oil consumption, no missing, starts fine, plugs haven't fouled. Bike accelerates, cruises fine and passing power fine, no smoking, maybe feels a bit lazy.
Replaced TPS (faulty) last season, new ETS on spec a few weeks ago. Checked TPS and made minor adjustment to 275V cold /.675 fast idle. I think the procedure was right but I'm not convinced it has properly re-learned Min Throttle Position. Actuator seems to be functioning right. TP bleeders are clear and no significant oil in clean K&N a/c.
Checked, cleaned Injectors (looked fine) and replaced o-rings while I was there last year. Checked regulator last year.. pressure OK.
I am thinking IAT or Baro sensor failing(long shot), or maybe wiring continuity problem since they share BK/W wire (along with ET, TPS and Cam sensors) back to ECM. This seems a bit strange to me because ISC Actuator seems to be working, but the ET part of the loop may be ok.
btw, last year was only 5K miles ago.
I have NO faith in local dealers' ability to find and fix much and I will not be establishing a college fund for them single-handedly.
If this continues i'll be looking at carb conversion.
Do you think I am looking at the right area for the fuel problem, and possibly also the idle issue too?
Any practical way to test the continuity of the wires easily since I only have a multi-meter?
Other thoughts worth pursuing?
Plugs in the pics are the same plugs, just different angle of shot.
Sorry for this being sooo long but i've been playing with it for a while now.
TIA.

[2000FiveOh]

350 miles on ONE tank of gas? I'd really have to see that to believe it. If you were getting 350 to a tank, a 10% drop would only be 35 miles. How did you go from 350 miles per tank to 180? Your math doesn't add up.

Anyway, recheck the TPS voltage. They are really finicky and the slightest movement will throw them off ALOT. Then set your cold to .65. Disconnect the 5 and 15 amp fuses for an hour or so. While your waiting, clean ALL your contacts with CRC or some other contact cleaner. ECM connector, sensor connectors, and all the connectors between the ECM and sensors. Warm it up and set the warm to 1000. Then adjust your idle mixture. Readjust your warm idle if needed. Cold idle is done by voltage, warm idle is set to 1000, mixture should be set by a sniffer. I didn't have access to a sniffer so backed both out until I started to get a slight roughness then back in a hair.

If none of that does any good you need to start looking for a bad sensor or a sensor out of spec.

[dunbarton]

Originally Posted by 2000FiveOh

350 miles on ONE tank of gas? I'd really have to see that to believe it. If you were getting 350 to a tank, a 10% drop would only be 35 miles. How did you go from 350 miles per tank to 180? Your math doesn't add up.

Anyway, recheck the TPS voltage. They are really finicky and the slightest movement will throw them off ALOT. Then set your cold to .65. Disconnect the 5 and 15 amp fuses for an hour or so. While your waiting, clean ALL your contacts with CRC or some other contact cleaner. ECM connector, sensor connectors, and all the connectors between the ECM and sensors. Warm it up and set the warm to 1000. Then adjust your idle mixture. Readjust your warm idle if needed. Cold idle is done by voltage, warm idle is set to 1000, mixture should be set by a sniffer. I didn't have access to a sniffer so backed both out until I started to get a slight roughness then back in a hair.

If none of that does any good you need to start looking for a bad sensor or a sensor out of spec.

The 300-350 is metric.. km, the 180 is miles. Either way, it's down 10-20% which is a pretty significant change.
I will have a look at the connectors as suggested, but what about the wiring? I was wondering about continuity testing and the likelihood of picking up a bad wire. Without a breakout box, if I can't find the specific problem ie open connection etc, I may be spending a long time on it.

[klondike]

I run the MM and it is a bit of black magic it seems to keep it running straight. To set the cold idle you have to let the bike warm up to operating temp. Take off the sensor on top of the throttle body. Remove air cleaner. On the side of the T.B. is a screw. This is what you use to adjust the cold idle rmps to where you want them. When the bike is warmed up and the top sensor is removed sometimes the bike will idle high by itself but after a minute or so it should idle back down, at least mine did. When adjust cold idel setting I believe you should look at something like 14-1600 rpms cold idle.

Now you can set the warm idle too. That is done with the screw on the front of the T.B. Plug the top sensor back in and use the adjustment screw to set the idle warm. I ususally go 100 rpms over what I am looking for. Matter of fact with a modified motor like on mine I set the cold idle start at about 1800 rpm's and the hot idle to 1100 rpm's.

Ok now that this is done turn the bike off and remove the 5 and 15 amp fuses under the right side cover. Let the bike totally cool down. It might take a few hours to do so. After it is cool to touch, reinstall the fuses and then cycle the EFI 6-10x so it learns the new positions. Don't start the bike just cycle the EFI. Hopefully this will work. Sometimes you can get away with adjusting the TPS on the side of the T.B. but it is finicky to do but it can be done. Mine works most of the time pretty decent and what ever slack may be in the hot idling I work into the DFO I run using the rpm settings. It's a piece of **** system the MM but once you get used to it it is just screwing around with it to make it run properly. They also do not like hot weather no matter what. Hope this helps.

PS your battery and electrical system also needs to be about perfect too. Battery has to definetly be up to snuff this is very imortant.

[dunbarton]

Thanks for the reply and suggestions Klondike. I've been around the horn on setting the idle speeds before using this and other variations and the ECM min throttle position isn't taking.
When i get some time and ambition I will start looking at the electrical continuity of the wiring and connectors to those sensors tied into the hot/cold idle.. ie ET, IAT, TPS, Baro and CPS.
Since the fast idle stepper does work, I'm assuming information is passing from the ET but I'm not sure about the IAT. If it wasn't such a pia, I would pull it off and have a closer look at that potential villain. I'm a little nervous about pulling the throttle body off, but that is what is required to get at the IAT.
It would be nice to have a breakout box if that allowed me to remotely test each sensor live.

[U3270]

Has anyone done a cost effective MM to Delphi conversion (or other brand)? The stuff I have seen in magazines in quite expensive.
Thanks

[dunbarton]

Originally Posted by U3270

Has anyone done a cost effective MM to Delphi conversion (or other brand)? The stuff I have seen in magazines in quite expensive.
Thanks

Quite expensive is a relative term.
From what I've learned, there are a number of after-market solutions including Thundermax conversion kit which is designed for this purpose and prices out in the $2000 plus range.
An alternative is to convert the MM to carb, which totally eliminates the FI. Basically those sensors and overlay harness are eliminated (removed) and a carb of your choosing and intake manifold replace the FI throttle body. The fuel pump is removed and the gas tank reverts to gravity feed. It appears the coil may have to be replaced as well, but there is conflicting advice on this.
The material price for this seems to be in the $500-1000 range depending on which carb and coil is chosen, and if you are using new or used parts. The parts and wiring diagram for the final configuration are laid out in the HD Service Manual since a carb version of the FLH was available for the 2000 model year.
Of those who have done the carb conversion seems quite pleased with the result in that it provides what might be called satisfactory performance and reliability, contains the costs and avoids future FI issues.
The satisfaction with the Thundermax kit solution appears to be mixed. Although the performance side is good, the cost is a pretty big pill to swallow, especially for what is now an older bike. Some , if given the opportunity again, would have preferred to have gone the carb route and kept more of their jingle in their pocket.
This is what I understand from reading the numerous threads here and elsewhere.

[2000FiveOh]

Cold idle is set with the engine cold. Like I said earlier...adjust TPS to .275...then turn your cold idle screw until you get .65 volts (with IAC disconnected). .65 will set your cold idle exactly where it needs to be.

You dont need a breakout box to test for continuity. Just follow your wiring diagram for the ignition harness.

If you can't get it right and it starts driving you crazy I'd do the carb swap. I plan to do the swap if mine ever gets unbearable. Spending 2 grand on a 10 year old bike just doesn't make much sense to me. Others may have money to burn though. You can do the swap with a CV carb for under 400 in parts and a Saturday afternoon.

[dunbarton]

Originally Posted by 2000FiveOh

Cold idle is set with the engine cold. Like I said earlier...adjust TPS to .275...then turn your cold idle screw until you get .65 volts (with IAC disconnected). .65 will set your cold idle exactly where it needs to be.

You dont need a breakout box to test for continuity. Just follow your wiring diagram for the ignition harness.

If you can't get it right and it starts driving you crazy I'd do the carb swap. I plan to do the swap if mine ever gets unbearable. Spending 2 grand on a 10 year old bike just doesn't make much sense to me. Others may have money to burn though. You can do the swap with a CV carb for under 400 in parts and a Saturday afternoon.

I've gone thru the TPS setup and it's on the money. Still no luck on getting the min throttle position to take.
When I get inspired I'll do some testing and check the connectors etc. This is probably best done with the gas tank raised out of the way. If that doesn't show a fault then I'll be going the carb route.
I'm skeptical of the $400 est unless a very cheap carb should fall into my lap. A CV is certainly my choice and I'm hoping would allow me to re-use my cruise control. I might get a good takeoff carb but local dealers/shops will want most of the price of a new one I bet.
I have heard conflicting advice on the coil. Do you know with certainty if that needs to be replaced or the original can be reused? A new coil and carb would likely top $600 themselves even from the HD discounters.
I'm lucky that the bike is fully operational so there's no urgency. It usually gets mothballed for the winter months (Nov-Apr) so that's the time to gets parts lined up if necessary.