Rough idle backfire

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Mar 2, 2023 | 08:02 PM

DWMauney

Thread Starter

Stage IV

Joined: Mar 2023

Posts: 4

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From: Palm Beach County

Rough idle backfire

I have a 2000 Ultra Classic. It is having mutiple issues. Ran great. Went out for lunch. When I tried to start to give home all these issues started.

high rough idle
backfiring
Tach not working
Check engine light on

I have did the following repairs to no avail
New spark plugs and wires
new gaskets and clamps on throttle body
new gaskets on air intake
New air filter
Tried to check codes. All banks say clr when in diagnostics

Any ideas would be helpful

Mar 2, 2023 | 10:41 PM

Black Ultra

Road Master

Joined: Feb 2023

Posts: 959

Likes: 839

From: Hudson, CO

well, what could have happened while you were at lunch? My first thought would be vandalism. Like maybe something in the fuel, or a cut wire. If i were in your shoes, I would remove the tank and wash it out, replace the fuel filter and look hard for any wires that could be easily accessed.

I hope I'm wrong. Good luck.

Mar 3, 2023 | 08:58 AM

euchre98

Road Master

Joined: Aug 2006

Posts: 766

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From: Calvert, MD

Fuel injected bike? If so the Marelli system that was used then is famous for intake leaks.

Mar 3, 2023 | 09:47 AM

BrokeWinger

Cruiser

Joined: Jul 2022

Posts: 231

Likes: 100

From: WI

Did you get gas?

Mar 3, 2023 | 12:28 PM

DWMauney

Thread Starter

Stage IV

Joined: Mar 2023

Posts: 4

Likes: 0

From: Palm Beach County

Quote:

Originally Posted by euchre98

Fuel injected bike? If so the Marelli system that was used then is famous for intake leaks.

I replaced the gaskets and flanges. After installing also sprayed cleaner around while bike was running. No intake vacuum leaks.

Mar 3, 2023 | 12:30 PM

DWMauney

Thread Starter

Stage IV

Joined: Mar 2023

Posts: 4

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From: Palm Beach County

Quote:

Originally Posted by BrokeWinger

Did you get gas?

yea earlier in the day. Ran a half tank through with no issues. Got more gas on the way home. Another half a tank ran through. Still rough.

Mar 3, 2023 | 07:37 PM

seniorsuperglideE8

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Joined: Jan 2007

Posts: 15,788

Likes: 5,622

From: along the shore of Mishigami

If you have a crank position sensor in the front of the engine, unplug and reconnect. Or with that year the Crank position sensor maybe in the nose cone on the cam chain cover. Hopefully some with the knowledge of this CPS will chime in and walk you through the diagnostics. The CPS triggers the ignition circuit to fire the plugs.

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Mar 16, 2023 | 10:21 PM

Black Ultra

Road Master

Joined: Feb 2023

Posts: 959

Likes: 839

From: Hudson, CO

Have you tried some fuel system clearner? maybe a partially clogged injector? Maybe a new fuel filter?

Last edited by Black Ultra; Mar 16, 2023 at 10:23 PM.

Mar 17, 2023 | 01:06 AM

#10

kojak

Seasoned HDF Member

Joined: Jan 2007

Posts: 5,604

Likes: 4,045

From: Virginia

Quote:

Originally Posted by DWMauney

if the check engine light is on, there is a malfunction detected by the ecm. On the earlier EFI models, the dealer can pull codes that won’t show on diagnostics from what I understand. Good luck on getting the problem resolved.