Qjet idle issues
Thread Starter
Instructor
Joined: Aug 2010
Posts: 233
Likes: 18
From: Monrovia Md
Qjet idle issues
I just rebuilt an E4mE (1981 CCC carb). Put it on the car, started right up, choke engaged , fast idle perfect, kicked off when it warmed up then stumbled and died, increased the idle speed, 1100 out of gear, 900 in gear and it idles pretty good (a small skip every 5 seconds). Took it out on the road, great throttle response, great transition from primary to secondary, drives great.
Bring the rpm down to under 1000 and it stumbles and stalls.
Checked all the vaccuum ports, all look good (the carb I replaced it with ran great at idle). Seemed to be idling a little rich ( eyes stinging meter) so I turned the idle screws in to about 2 turns out for each, same issue
No check engine light
Any thoughts as to what to look at next?
Bring the rpm down to under 1000 and it stumbles and stalls.
Checked all the vaccuum ports, all look good (the carb I replaced it with ran great at idle). Seemed to be idling a little rich ( eyes stinging meter) so I turned the idle screws in to about 2 turns out for each, same issue
No check engine light
Any thoughts as to what to look at next?
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Did you do the rebuild? Did it get soaked in carb cleaner for a few hours and all orifices blown out with compressed air? It sounds like a problem with the idle circuit. It could be an idle tube that is plugged or damaged or something similar.
Thread Starter
Instructor
Joined: Aug 2010
Posts: 233
Likes: 18
From: Monrovia Md
Yes, rebuilt it myself. Soaked it for a long time, but I was thinking the same thing that there is still some junk in the idle circuit passages. Seems like its coming apart and I will clean all the passages again
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Since it is running well at "off idle", "cruise", and WOT, there must be a blockage/leak/damage in the idle circuit somewhere.
If you did not remove and clean the idle air tubes, that is the first place to look. It is also possible that one of the drilled holes for those idle air tubes was not drilled deeply enough and is actually blocking the proper operation of the tube. Use a drill or drillrod to check the depth of each hole and compare it to the length of the tubes to be sure there is clearance for the tube ends.
If you did not remove and clean the idle air tubes, that is the first place to look. It is also possible that one of the drilled holes for those idle air tubes was not drilled deeply enough and is actually blocking the proper operation of the tube. Use a drill or drillrod to check the depth of each hole and compare it to the length of the tubes to be sure there is clearance for the tube ends.
Last edited by 7T1vette; Jul 7, 2012 at 08:54 PM.
