Old riding buddy of mine has a 1999 TC88 Police Road King (FLHP) with MM (Magneti Marelli) fuel injection, just bought it last fall. He's been riding since the 1960s, but never had a Harley before; it's his pride & joy. I hate to add another post to the MM cold idle adjustment saga, but we've tried everything and we're really at a loss here.

YES, I've read the posts on how to set the cold idle on MM injected bikes, all several thousand of them. Bought a #10 Torx driver and tried them all too, including the two on the sticky post in the DIY section. Sometimes we unplugged the harness from the actuator (on top) & adjusted the cold screw (on the forward side), sometimes we unplugged the air temp sensor (aft side intake) & adjusted the cold screw. We tried the method in the 99 manual, no luck. Then tried the method in the 98 Evo/MM manual (which swaps step 7 & 8 from the 99 manual), again no luck. We tried plugging wiring harnesses back in before we shut off the bike, and we tried shutting the bike down then plugging them back in. And yes we always pulled the 5 & 15 amp fuses for half hour after shutting the motor off. We pulled the ground off the battery once or twice too, just in case pulling fuses wasn't enough to reset the memory. I can adjust the cold idle to 1500 before shutting down & pulling fuses, but the cold idle setting won't stick.

I can see the actuator moving in/out when we turn the ignition off/on, so I'm thinking the actuator is good. The bearing on the forward side looks/feels fine too. We cleaned the everything with carb cleaner, cleaned the little bleeders on top/inside of each chimney too, and put a little WD40 on the moving parts just to help free stuff up. The bike takes and remembers changes to warm idle (screw low/right behind air filter) just fine - warm idle returns to wherever we set it, and the bike remembers it. The bike runs & idles fine when fully warm, but there isn't much warm this time of year.

EDIT: Yes, we looked at Service Bulletin M-1105 (Aug 2000) but can't do much there without a Scanalyzer.

But when the bike is cold, she starts long & hard, coughs, runs rough (lean?), then tries to idle at 700, no matter what we did. If we don't goose the throttle she'll just die out. The bike isn't throwing any codes, check engine light goes off & stays off. (EDIT: We later learned this bike does store codes, but the engine light doesn't come on to indicate a stored code like later bikes. Only way to check for codes is to flip the ignition switch a few times and actually retrieve them. We learned this a few months late when the crank position sensor crapped out).

Is there something about a police bike that would change the way we set cold idle on Magneti Marelli fuel injection? Also, I notice the Diagnostic Trouble Codes (DTCs) are shown as for 00-03 bikes. Why not 99-03? Was 99 different? I know 04 (my bike) was the start of the new ECM.

What are we missing here? What can we do to make my old riding buddy's bike idle right when cold? We're both at a loss. Any and all input greatly appreciated.

Much thanks in advance,
JR

 

Not trying to be a smartass, but take it to a dealer. I kept messing with mine and it drove me nuts. I kept stalling during warm idle. Finally too it to the dealer and they fixed the cold idle and replaced a crank position sensor. Should be fairly cheap to get the idle fixed.

 

+1 for the dealer. It wont cost much.

 

Sounds like a intake vacuum leak. things warm up and expand and seals up the joints. I ride a 99 aand had similar issue, was intake manifold seals. Good luck.

 

Subscribed...

Just did a big bore / gear drive. Put 1500 miles on it and took her to a highly rep tuner in my area. Charges a decent amount for a tune, really dials 'em in. I've got the same EFI tho it's not a cop bike.

The guy rides the bike for 10-15 minutes then comes back. Gets off the bike and says he doesn't want to take my money...bike runs real good. Then he pulls the plugs, they look good. Pulls the oil dipstick...no gas smell in the oil. Says the cold idle is a bit low, I've HAD to adjust the warm idle. When I told him I adjusted through the A/C cover, he remarked that 20 year HD techs make the same mistake.......huh? Got to honor a fellow who doesn't wanna "gouge" a fellow biker on a tune!!

Went on to explain that the potted screws need to be adjusted. Asked him where a fella was to find this printed information...he said it ain't out there.

Told me to just ride the "chit" out of it, and enjoy it.

Stop by a dealership to inquire....
They want me to drop her off for an entire EFI overhaul.
Then there's the check valves, fuel filter (changed that,) and a host of other odds and ends they want to pile on.

Bike runs like a beast anywhere off part throttle...

Gotta figgure out the idle to part throttle. 8 out of 10 times she does fine from a stop, but 2 out of those 10, she'll backfire or sputter.

Hope we get some info...I'm after 10 outta 10.

Where's all the MM Guru's???????

Beav

 

It reads like you have taken very logical steps to approach a solution.
seems like bike runs well when warm but has issues when cold correct?
Does that year have an intake air temp. sensor at the induction module which is located on opposite side of idle speed control actuator? (plastic piece with two screws/wire plug)
That thing works with other sensors for cold start-up. A lack of resistance or grounding would probably be read as engine being hot and create cold start issues.
Also, is this a bike ridden on salty roads? check the connectors..the metal connectors at ECM and cable for corrosion and clean. Make sure the rubber cover is good for this connection. Check the wires/connections from the sensor mentioned again and clean.

 

Thanks im. Correct on the warm engine - when warm all is good. And yes the bike has an intake air temp sensor on the aft side of the rear intake. One time I disconnected it with the engine warm, and the engine shot up to 4,000 rpm. I turned the cold idle down to 1,500 and put the temp sensor harness back on and speed dropped back to 1,000 (normal warm idle). Then we shut her down & pulled the 5/15 amp fuses for half hour. Next cold start; hard starting & idled at 700 again, running rough & threatening to stall again. There's no corrosion anywhere on the bike. All connections are spotless clean, like the rest of the bike.

JR

 

When I had my '99 the dealer had what they called the M&M tune up. I guess the throttle plates wear into the bore. They reset everything due to the wear. Wanted it overnight for the cold start. Worked fine after that.

 

Went through this when I replace the IAC on my bike. IIRCC you need to have the voltage set correctly at the TPS

http://www.hdtalking.com/diagnostics...injection.html

If this value is not set correctly you cannot properly set the cold idle (I know I tried). I am not at home where I have the values where you need to set it, but when I get home tonight I will fill you in on the rest of the proceedure.

 

I agree on the Throttle Position Sensor. But I went by the manuals instructions of setting the voltage on the TPS with a voltage meter and it failed to idle correctly. With the bike at operating temp, do this, barely loosen the 2 screws on the TPS so you can easily adjust it, before you crank the engine. Crank the bike and move the sensor till it is idling perfectly. Tighten the screws back down. Ride the bike and it may need a little adjustment, but probably not. The cold idle will need resetting after you do this.