2000 FLHTC won't idle down

[FLH_Rider]

I am working on a 2000 FLHTC that is fuel injected, it won't idle down and will start to increase in RPM after a few about 30 seconds,
some background, it had been in a wreck, the owner replaced the front end and removed bags, guards and mufflers. I believe it was laid down on the right side. intake had a bunch of oil in it. I sprayed carb cleaner in it and cleaned it out some. Still won't idle down.
Should I take all the sensors out and clean them or is there something else I should be looking at.
Also, right now the mufflers are off and air filter is not on.

I am in the process of straightening guards and reinstalling everything.

Recommendations,,,,,?

Thanks in advance,,,,,

[Hossamania]

Put the mufflers on and try it again.

[xlfan]

Look up Service Bulletin M-1105 down in the instruction sheet section, if mufflers back on doesn't help.

Follow the outlined procedure.

[Scotty]

As long as all sensors are good and everything including the intake seal are in correctly. Since bike dropped on right side I would check if throttle body moved and if intake seals need replacing just as a start. Now since most people don't have a Scanalyzer laying around the work shop here is a method for setting hot and cold idle on a MM equipped bike the easy way. I did not writie it and don't know who the original author was but maybe he is still a member on here.



The ECM will control cold engine idle speed only by moving the idle speed control lever to open or close the throttle plate. It does this by sending voltage pulses to the proper motor winding of the ISC actuator. This is step one in setting the idle, regardless. This is measured in counts and that's the ONLY THING the Scanalyzer is used for. There is only ONE change the Scanalyzer can make – If the bike has a stage kit, the Flash Cartridge will change the TPS low voltage to about 12 counts (can't remember the exact number). Even after a Flash the following process must be done before customer delivery. Without the Download Cartridge, you can't change this count. You can only check it with the Scanalyzer. The Scanalyzer beyond this point other than checking the Engine Temperature is USELESS unless you need to chock the wheels.


Here is the way around using the Scanalyzer: When bike is COLD (has sit for a few hours)

1. Disconnect any fuel optimization device! Remove 5 AMP fuse for the ECM. This only has to be done for a minute or two – Learned Memory is GONE. Now, Disconnect the ICS Actuator. Start the motorcycle – Set the Fast Idle Adjustment to 1600 rpm (this sets the pulse with count to the bikes current configuration – no cartridge needed)! Turn bike off. Reconnect the ICS. Remove 5 AMP fuse for the ECM and reinstall. New setting will be recorded when ICS actuator goes through its first cycle (about 8-10 seconds following power up of the ECM). Turn to Run (DON'T Start the Bike) The Actuator will Retract and then Extend During 8-10 Second. Turn ignition OFF.DONE WITH COLD IDLE SETTINGS!

2. Start and ride the motorcycle until HOT– at operating temperature. About 225 degrees. Remove the Air Cleaner, using a Torx 10, adjust the warm idle screw to 1000 rpm. Remove 5 AMP fuse for the ECM and reinstall. ECM thinks it's cold. Start bike Idle should advance through its first pulse count and accelerate to about 1200 rpm and immediately fall. With each pulse count it will continue to drop until the warm idle set screw doesn't allow the tps to fall any further – 1100 RPM (Takes about 8-10 seconds). YOU ARE DONE! Don't ever touch it again.

Cruise Control Following Cable Install:

1. The MM requires about ½ inch MINIMUM of free unobstructed movement of the throttle grip/cable. This is BOTH cables. The cruise control uses the return cable to maintain its speed. Anything tighter will send pulse counts to the ECM for the circuit that are incorrect causing late engagement or disengagement.

2. Enter the Cruise Diagnostic Mode. Regardless weather any stored codes are present, follow the direction to clear them. CCU, now is back to stock delivery settings.

3. Go through the setup process and the CCU will re-adjust strap length sending pulses to the ECM until it receives resistance pulses from the ECM – YOU ARE DONE! Don't ever touch it again.

4. Test Drive the Motorcycle. Cruise should engage and disengage smoothly.

5. if not, readjust the cables as described and retest.

Here are some things to remember when troubleshooting the MM ECM Fuel Management System.

1. The idle will bounce slightly The ECM reads sensor position as opposed to sending pulse signals like the Delphi. There is a delay of about 1 second with each pulse.

2. Not riding the bike after starting it any distance and turning it off confuses the data count. Always start it when you're ready to ride. Not moving it across the driveway to run the leaf blower after cutting the grass.

This is 1993 Technology that didn't hit the first HD until 1995. The throttle body is similar to a 1980's GM TBI System. The Baggers were the only ones to see it excluding the Screaming Eagle Bikes which had it as an option. Comparing the MM to the Delphi is like com paring a Widows Based PC with a MAC – Totally different in its core operation is five sensors, and the Delphi is ever growing. It that's not enough, HD has added a Body Control Module (BCM) to the next generation EFI System.

The first Generation TTS can be installed  and adjusted on MM. Anything that followed can not. Hence the numerous piggy-back systems out there for 95-01.

[FLH_Rider]

thanks for the info, as soon as I straighten some of the saddlebag guard i will get the mufflers on and give it a try.
The owner is the one that told me about the idle and I had tried it. I had a notion no mufflers might contribute to the issue,,,

[72fl]

It's the dreaded Magna Marelli Injection before ya get to throwing a bunch of time and money into it, buy a Fuel Pak that adjusts either automatic or manually. Google it you will find several answers or do a search on here about  Marelli

[rigidthumper]

It's the dreaded Magna Marelli Injection before ya get to throwing a bunch of time and money into it, buy a Fuel Pak that adjusts either automatic or manually. Google it you will find several answers or do a search on here about  Marelli

There is no Fuel Pack for Magnetti Morelli equipped HDs.

[Pirsch Fire Wagon]

As for Fuel Optimizer's, I found the COBRA 692-1603B works pretty well. But, they are EXPENSIVE.

You can still get the Thundermax but it takes about six weeks to get it as they no longer have them on the shelf as I understand. They assemble and sent out.

The DynoJet USB 3 wasn't bad but, it seemed to fail rather quickly on the ones I tuned.

There is still the option of the SE Tuner, if you can find one.

[SP33DY]

As for Fuel Optimizer's, I found the COBRA 692-1603B works pretty well. But, they are EXPENSIVE.

You can still get the Thundermax but it takes about six weeks to get it as they no longer have them on the shelf as I understand. They assemble and sent out.

The DynoJet USB 3 wasn't bad but, it seemed to fail rather quickly on the ones I tuned.

There is still the option of the SE Tuner, if you can find one.

I just got a T-Max kit to replace the Magnetti Marelli on a 2000 ElectraGlide. Took about two weeks. Be sure to also order the fuel line kit 117-065, and a set of angled O2 sensor bungs 272-201.
You can cut your old fuel lines and re-use them if they are in good shape. The ones from this bike were practically rubbed through and dry rotted.

[Deye76]

"It's the dreaded Magna Magneti Marelli Injection before ya get to throwing a bunch of time and money into it"

Check the fuel lines inside the tank and the pressure regulator. Better yet ditch it for a carb, you'll be money ahead by the time you get it sorted out.

[Hossamania]

"It's the dreaded Magna Magneti Marelli Injection before ya get to throwing a bunch of time and money into it"

Check the fuel lines inside the tank and the pressure regulator. Better yet ditch it for a carb, you'll be money ahead by the time you get it sorted out.

It's sad but true, a friend did this last year with an '01 RoadKing he purchased.

[chipthedonkey]

I was never a hater where the Marelli systems were concerned.  Owned four M&M bikes of own over the years and tinkered/maintained those of others who brought beer to my garage lift.  Despite all the rancor one often hears they were a serviceable system.  They had their quirks but they could be maintained.

Having said that it's to the point that for significant maintenance or repetitive issues; probably not anymore.  Worth it to consider some retrofit/revision/change.  Parts are getting harder and harder to get and may the Travel Gods help you if you break down on the road somewhere.  Kids in a contemporary dealership best guess will be Magnetti Marelli is an Italian hip hop group.

Carb conversions are easiest and (generally) cheapest.  Conversions to 04-05 era Delphi are easy too though more involved and more expensive than just a carb swap.  Cruise module, gauges, harnesses, ECM, all the works in the tank, battery box and a little tinkering making the fuse panel fit.  But it's still a good weekend job once you've got all the parts in hand.

I've done two of the Thundermax "upgrades" of Marelli.  Strictly one guy's opinion, not a fan.  If you've got time to shop for parts and buy well you can do a Delphi conversion for less money and have something "normal" when you're done.

Basic maintenance is still ok on a Marelli bike.  If it starts getting more involved or is beginning to have some repetitive problem, however, yeah, if you love the bike and plan to keep it it's time to start shopping for parts.

[twincamzz]

Seems like I remember that if the head temperature sensor goes bad the idle will be high. But will readily admit it has been awhile since I worked on  a Magnetti  Marelli system. 

[blacknightrain]

Seems like I remember that if the head temperature sensor goes bad the idle will be high. But will readily admit it has been awhile since I worked on  a Magnetti  Marelli system. 

Exactly what I was going to say.  My 98 used to idle up sporadically.  I changed out the head temp sensor and all was fixed.  Try to pull the negative battery terminal for 10 seconds to get the ECM to reset.  If that isn't it, I would look at the intake seals.

[Rodman]

If it fell on the intake side I would be looking at the throttle position sensor.
If the IAC retracts all the way at key off then steps out to the learned home position then that's enough for starters.
If someone tried to start the bike with an almost dead battery and wiped the learned position from the ECM from low voltage, it will end up with either a high idle or no cold idle after the battery is charged or replaced, and the re-learn has to be completed.
An analog ohm meter can display the TPS quite well, either a smooth needle response to increase and decrease of throttle, or a jumpy needle that tells you it's FUBAR'd. It wouldn't hurt to tap the TPS with the butt end of a screw driver, to see if the Idle changes.
My money is on the battery was half dead and he tried to start it, thus trashing the learned position. Ask if he had to charge a dead battery at some point.

[FLH_Rider]

original post -I am working on a 2000 FLHTC that is fuel injected, it won't idle down and will start to increase in RPM after a few about 30 seconds,
some background, it had been in a wreck, the owner replaced the front end and removed bags, guards and mufflers. I believe it was laid down on the right side. intake had a bunch of oil in it. I sprayed carb cleaner in it and cleaned it out some. Still won't idle down.
Should I take all the sensors out and clean them or is there something else I should be looking at.
Also, right now the mufflers are off and air filter is not on.
I did as Scotty recommended for the method without thee the scanalyzer, I was able to get the bike to idle and it will run alright but does not throttle done quickly, when I take it for a ride not it will not idle down it idles at around 3500 rpm, it will also cough a little around 2500-3000 rpm when riding a steady throttle, will not cough when throttling up.
I took it to a guy that had a scanalyzer and code reader, neither one would link up.
Would this be something totally different or part of my issue.
When the key is turned on the idle speed control actuator moves out slightly, I have not taken the air cleaner off after a ride to see what it does.
Intake gaskets and injectors have been changed, also the speedo does not work so can not see if it is throwing a code

looking wiring over to see if anything is wrong or not plugged in,,,,

Thoughts,,,,

[kd]

The engine temp sensor does not throw a code.  The only way to confirm it is to try a known good one.

[PBSTN]

Engine temperature sensor. ETS.  Had this happen on my 01 road king.  Easy fix.

[fleetmechanic]

 We have a now retired 1997 FLHTP with the MM system.  For some reason it needed a new ETS at about every 8,000 miles.

[kd]

I have found it happens often enough on my 2 98's that I have a spare and it travels with the bike(s) on trips.  You can just lift the tank enough to access it on the front cyl head to change it.

[Rodman]

Engine temp sensor can be checked with an Ohmmeter.
32°f - 9750 Ohms
50 - 5970
77 - 3000
140 - 746
176 - 377
230 - 153

At high temps resistance is very low as you can see.
If the engine is cold you can compare the readings from the Engine temp sensor to the Intake Air Temp Sensor for
baseline,(They should be about the same) and then obviously the resistance of the engine temp sensor should change during warm up.
The sensor uses a 5v reference signal, so any change to the reference voltage changes the output.
You can check reference voltage across the two pins for the sensor with the ignition/run on and sensor disconnected.
The sensor has to fault hard beyond it range to fire the code which is DTC 14.
If you unplug the ISC when you see it step back, you can then the start the thing and see if you still have a high idle, and if you do the ISC isn't causing it. The next thing to look at if there are NO Vacuum Leaks is the TPS.
It uses a 5v reference signal as well.....has 3 wires:
Red/White is the reference input
Black/White is the clean ground
Grey/Violet is the signal to the ECM
With the Throttle closed there should be a 0.2 - 0.4 v signal being sent to the ECM
With the Throttle wide open there should be a 4.6 - 4.9 v signal sent to the ECM
You can read this across the Signal and the clean ground if you back pin with a DC volt meter.
Twisting the throttle slowly open should show a smooth increase in voltage, as well as repeatability.
Hope this Helps....

[booker49]

i have the same bike. it happend to me also. i followed the service manuels easy fix. trun the bike off. turn the throtle all the way open(with the engine off) turn the ingnition on for 4 seconds. do this 4 times in a row .let go of the throttle. start the bike- it should idle normal.