Weird idle...
Thread Starter
Le Mans Master
Joined: Jan 2003
Posts: 6,575
Likes: 1
From: Tuttle OK
Cruise-In VIII Veteran
Weird idle...
...Just started after a 450 mi round trip drive. I first noticed a flat spot during take off when I was close to home.
Looking it over after I got home, I noticed it will idle at 900 for about a minute then down to 600, back up again, etc. Seems to be fuel related, but might not be. Fuel filter seemed easy to blow through. While checking the fuel filter, I noticed that fuel continued to come out of the fuel line. Normally, it quits a short time after I remove the line.
I’ll continue my investigation tomorrow, but any thoughts?
Looking it over after I got home, I noticed it will idle at 900 for about a minute then down to 600, back up again, etc. Seems to be fuel related, but might not be. Fuel filter seemed easy to blow through. While checking the fuel filter, I noticed that fuel continued to come out of the fuel line. Normally, it quits a short time after I remove the line.
I’ll continue my investigation tomorrow, but any thoughts?
Thread Starter
Le Mans Master
Joined: Jan 2003
Posts: 6,575
Likes: 1
From: Tuttle OK
Cruise-In VIII Veteran
because fuel continued to leak out of the fuel line for so long, i almost suspect the fuel system somehow...
also noticed that my timing varied as well (via timing light), but think that's more related to the rpm change..
haven't checked enough stuff yet to make a real diagnosis ...
also noticed that my timing varied as well (via timing light), but think that's more related to the rpm change..
haven't checked enough stuff yet to make a real diagnosis ...
Last edited by Avette4me; Jan 16, 2006 at 03:41 AM.
Race Director
Joined: Sep 2004
Posts: 11,874
Likes: 263
From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
put your timing light on the engine while its doing this and see what the timing is doing....then disconnect the vaccuum to the distributor and see whats its doing...
Thread Starter
Le Mans Master
Joined: Jan 2003
Posts: 6,575
Likes: 1
From: Tuttle OK
Cruise-In VIII Veteran
Originally Posted by bobs77vet
put your timing light on the engine while its doing this and see what the timing is doing....then disconnect the vaccuum to the distributor and see whats its doing...
the vacuume is on a ported line.. do you think the ported line is unported somehow? never heard of that, but here's a lot i haven't heard of....
Last edited by Avette4me; Jan 16, 2006 at 07:23 PM.
Race Director
Joined: Sep 2004
Posts: 11,874
Likes: 263
From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
i'm not sure what to think.....what happened when you disconnected the vacuum line did the timing become stable?
this is waht i am thinking....something is not right in your distributor....it needs to be shimmed....maybe some bushings are missing maybe the springs are broken and the weights are flopping around...maybe the vacuum diaphram is torn and is opening and closing pullng in vacuum and then letting it go. maybe the shaft is wobbling.etc..etc..etc... unplug the vac can and let us know whats happening....hope fully Lars will step in and tell us whats going on as we stumble around...
can you put a T into the line going to the dist and see what kind of vacuum you are getting while this oscillating is going on?
this is waht i am thinking....something is not right in your distributor....it needs to be shimmed....maybe some bushings are missing maybe the springs are broken and the weights are flopping around...maybe the vacuum diaphram is torn and is opening and closing pullng in vacuum and then letting it go. maybe the shaft is wobbling.etc..etc..etc... unplug the vac can and let us know whats happening....hope fully Lars will step in and tell us whats going on as we stumble around...
can you put a T into the line going to the dist and see what kind of vacuum you are getting while this oscillating is going on?
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Thread Starter
Le Mans Master
Joined: Jan 2003
Posts: 6,575
Likes: 1
From: Tuttle OK
Cruise-In VIII Veteran
distributor shouldn't be broken, it doesn't have 2000 miles on it yet..but that could explain the oscillating...i'll check it (it will be tomorrow, have some people comming by)