My 98 FLHPI has some strange issues.

History:

I recently moved to Los Angeles from Washington State where my bike has spent the last 5 moths of winter in a parking garage. She was started maybe 4 or 5 times and ridden about the same. I have been in LA for a little over a month and I ride here at least 1-2 times a week.

I installed V&H true duals and Samson oval mufflers. The engine is stock otherwise.

Symptoms:

After riding the bike for a few minutes, the engine will start revving up to about 4-5k rpm for about 5 -8 seconds before settling back down to the regular 1200 idle. the engine light comes on during the increased RPM, and stays on for 4-5 seconds afterward.

It usually happens when I am stopped, but has happened while riding at 30-40 mph.

I have eliminated the throttle cables as I has recently lubed and adjusted them in hopes of solving the issue. The problem will happen when the bike has been idling for up to 15 sec or more at a full stop. Changing gears has no effect. Being in neutral has no effect. Working the throttle MAY have an effect, but I need to try it again to see for sure. Yesterday I opened the throttle while it was happening, and it slowed down after that. I don't think it is the throttle cables because the rpms will rise and fall with the throttle control held in the closed position.

I pulled the ECM fuses and let it reset for about 10 minutes, and then went for a ride. I rode around for 15 minutes or so, went into a store. On the way home it did it again. This time higher and longer than the last few times. Maybe the ECM is trying to dial itself in over a long period of time, and resetting it took it back to square one.

Could this be an ECM issue? Has anyone heard of this before?

Any help would be greatly appreciated!

Engine:

1340 evo with M&M injection

 

There is something wrong with your EFI. You will need a scanalizer to find and fix it.

 

Since the check engine light is coming on while riding.....you can pull codes yourself. The instructions are out here on the internet somewhere.

The hot idle needs to be adjusted to around 1000 RPM as well. The adjustment is either a small torx or allen in the bottom right of the throttle body. 1200 is too high. After the adjustment has been made, disconnect the battery.

To me, it sounds like head temp. sensor or throttle position sensor, or the idle control motor.

If you don't have any luck, then you gotta connect to a Scanalyzer or the HD digi-tech at a dealership.

 

After you pulled the fuses on the ECM did you resynch the ECMto the Idle Speed Control Actuator (IAC)? I know the manual says disconnect the fuses for 10 minutes, but sometimes that is not enough. I usually do 30 min to 1 hr. Then resynch the ECM & IAC, Key on 5 sec. Then Key Off 10 sec., repeat.

You can also try cleaning out the two small holes inside of the Induction Module. Spray some throttle body cleaner in there till they run clean.

Like EVO rider said though, chances are there is a problem with one of the sensors. Most often high idle is Head Temp Sensor.

 

1998 is evo, efi but M & M fuel injection not Delphi.
Highly likely that your engine temp. sensor in the chimney of front jug has died or is failing...but many times you get no code (engine light)..
It looks kinda sorta looks like a spark plug with a clipped wire connection going to it..
Look at J and P cycle website to see picture..costs about $100 at the dealer and requires normal tools for replacement.
to read you codes:
1-with handlebar switch on run...turn ignition key switch to ignition and then turn off 1 second after fuel pump stops.
2.repeat #1 again..remember 1 second after pump stops
3.turn ignition key switch to ignition and wait about 8 seconds for a bunch of flashing of the check engine light
it will then stop for 2 seconds..get ready... these are the codes you must count:
it will slowly flash 1,2,3,5....there is NO 4....this is the first digit of the 2 digit code ..so it can only be 1,2,3,5 __ __
then a 2 second pause...then you will get second digit of the 2 digit code..it can only be 1,2,3,4,5,6
remember after the complete 2 digit code is given you will go back to the rapid flash sequence..
there are a total of 15 codes available with this procedure
examples
52,53,54,55 bad news ECM replacement
56 crank/cam sensor
11 throttle sensor
12 barometric
14 engine temp. sensor
15 intake temp sensor
23 and 32 are injectors front/rear
24 coil
33 fuel pump relay--in this case you would not hear the pump but instead waited 3 seconds after the on / off sequence
update: Code 35 on Magnetti-Marelli EFI Systems
Normally a code 35 is set when there is a problem in the tachometer circuit. We
have identified another possible cause for a code 35 not specifically covered in the
Service Manuals. It pertains to a current or recurring historic code 35 (Tachometer)
on 1995-2001 EFI Touring models including Road Kings not normally equipped with
a tachometer. This code may be accompanied by codes 41, 42 or 56 and perhaps
even hard starting, poor cold idle and driveability issues. The ECM is functional
because it still has Key On power at pin 26.
Diagnosing this possible condition is relatively easy. Using the Scanalyzer, look for
consistent battery voltage in the data monitor mode (you may have to perform a
wiggle test while monitoring) because the Scanalyzer is monitoring voltage at pin 35
of the ECM (not battery voltage across the battery terminals). Closely inspect every
connection from the Main Circuit breaker to the ECM for loose crimps or
connections. Even a loose ECM fuse or intermittent ECM relay can cause this
condition.

 

1998 is evo, efi but M & M fuel injection not Delphi.
Highly likely that your engine temp. sensor in the chimney of front jug has died or is failing...but many times you get no code (engine light)..
It looks kinda sorta looks like a spark plug with a clipped wire connection going to it..
Look at J and P cycle website to see picture..costs about $100 at the dealer and requires normal tools for replacement.
to read you codes:
1-with handlebar switch on run...turn ignition key switch to ignition and then turn off 1 second after fuel pump stops.
2.repeat #1 again..remember 1 second after pump stops
3.turn ignition key switch to ignition and wait about 8 seconds for a bunch of flashing of the check engine light
it will then stop for 2 seconds..get ready... these are the codes you must count:
it will slowly flash 1,2,3,5....there is NO 4....this is the first digit of the 2 digit code ..so it can only be 1,2,3,5 __ __
then a 2 second pause...then you will get second digit of the 2 digit code..it can only be 1,2,3,4,5,6
remember after the complete 2 digit code is given you will go back to the rapid flash sequence..
there are a total of 15 codes available with this procedure
examples
52,53,54,55 bad news ECM replacement
56 crank/cam sensor
11 throttle sensor
12 barometric
14 engine temp. sensor
15 intake temp sensor
23 and 32 are injectors front/rear
24 coil
33 fuel pump relay--in this case you would not hear the pump but instead waited 3 seconds after the on / off sequence
update: Code 35 on Magnetti-Marelli EFI Systems
Normally a code 35 is set when there is a problem in the tachometer circuit. We
have identified another possible cause for a code 35 not specifically covered in the
Service Manuals. It pertains to a current or recurring historic code 35 (Tachometer)
on 1995-2001 EFI Touring models including Road Kings not normally equipped with
a tachometer. This code may be accompanied by codes 41, 42 or 56 and perhaps
even hard starting, poor cold idle and driveability issues. The ECM is functional
because it still has Key On power at pin 26.
Diagnosing this possible condition is relatively easy. Using the Scanalyzer, look for
consistent battery voltage in the data monitor mode (you may have to perform a
wiggle test while monitoring) because the Scanalyzer is monitoring voltage at pin 35
of the ECM (not battery voltage across the battery terminals). Closely inspect every
connection from the Main Circuit breaker to the ECM for loose crimps or
connections. Even a loose ECM fuse or intermittent ECM relay can cause this
condition.

 

Note: your bike is most likely running lean with the true duals and the samson slip ons..did you put a fuel management device to add fuel?...and the engine temp sensor does cause symtoms as described...the other common thing is difficult start-ups and a code 56 from a bad crank/cam sensor.

 

You guys are totally bad ***! I have lots to think about. The info on the flashing codes is priceless. I saw it flashing and felt helpless as to knowing what it meant. Now I can go out and take notes. I will get to the bottom of this with your amazing advice.

Thanks and I will post an update when I get a chance to read the codes.

 

Would it be cheaper to have this fixed by the dealer, or switch to a carb? I had to ask... I have heard the Magnetti Marelli EFI systems can be a lifetime of expensive maintenance.

 

I would find out what is causing the problems first....when you giveup trying to find the problem, then find a dealer or an indy with scanalyzer/breakout box.

If nobody else can find the problem or are building the engine up beyond what old Magneti can handle.....then switch to carburetor.