2001 Night Train EFI

OK, a buddy of mine has an 01 Night Train with EFI on it and he has a weird problem. When he pulls in the clutch the bike wants to die on him. I looked at his plugs and it is running lean and does pop on decel. Stock 88 with Samson Exhaust. Thoughts?

My O/Ls Heritage was doing the same. Sprayed carb cleaner in the port for the idle control valve. Bingo !

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Also added a little seafoam in tank for good measure. Runinig great now

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Ok first 1 trying to read a plug with today's fuel ain't getting you no were .2 01 is probably open loop Delphi with no 02 sensors .what running device is on it ? If no piggy back device is on it .does it have a stage 1 down load.?3 right above the idle air control valve there is a black vacuum cap coming off a small tube 3/8 in diameter make sure it's there if not replace it .if it's there make sure it's not dry rotted and cracked

Thanks for the tips guys. I will get back to you when its done.

That port that you are talking about, that is the one that is located at the top of the TB right?

yup that's it. Another web site suggested a bad idle control valve, so I thought let's try some carb cleaner first. Sprayed a good amount into the port and it did the trick.

Just a question for my own curiosity, doe's it start and idle correctly cold. Agree a vac leak or a dirty IAC are the most common as suggested by all.

It idles just fine when not in motion and I can pull the clutch in when it is just idling and no issues.

Now not understanding EFI all that much and talking to BaggerPaul, I do think that I have the issue narrowed down to two things.

The owner said that his speedo quit working. Well that tells me that the VSS is going funky. I popped the tranny dipstick out and that fluid was NASTY so I changed the fluid but I did not pull the VSS to clean it. After talking to BaggerPaul and checking out some video, the problem is either the IAC or the VSS or both. I am starting to lean towards the VSS because there is another symptom happening that I did not think was related, that symptom is that the turn signals no longer want to self cancel.

I'm feeling it's the vss now. O/Ls bike would run fine but cut out while slowing down(as she pulled in the clutch) also wouldn't idle in nuetral.

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Interesting, the more info = a quicker fix sometimes.

Yeah the fuel filter was cracked in my SG and the motor wouldn't go much higher than idle.

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Site just keeps duplicating HR k's post dont know why .any way pin number 33 in the wiring diagram for a 2001 night train it shows as being vehicle speed sensor input to ECU it also shares the same 5 V reference going into the vehicle speed sensor as all the other sensors as far as I know and as far as I can remember from all the years of working on Delphi fuel injection systems IAC home position has always been controlled by RPM signal and vehicle speed sensor input that way when you pull the clutch in or you come to a coast it brings the IAC back to home position and then starts raising the counts as you slow down.Thats how gm Delphi and harley as far as I know has been doing it for years with speed density.

Also I never said at any point in time that would correct acceleration ! As a matter a fact that was not stated to me as a problem only a stall condition .also in no way shape or forum am I a certified you tube or Internet mechanic .you will find my credentials are that of one who has educated himself at the school of busting my ass and or taken proper training in educating and years of hard knocks running a successful business.

BaggerPaul is correct, there are no issues with the acceleration on this bike whatsoever.

Just an update. This bike is fixed and running well. The VSS did fix the problem.