XKE runs rough when I stop at stop sign. If I shift into neutral, it smooths out

New gas tank, new fuel pump and re-built carbs, vacuum synced. Runs smooth when started but when I come to stop, it runs rough unless I shift into neutral?? Vacuum line leak??
Thanks for any help–Valkyrie Kid (Bob) '68 1.5 2+2 4.0L

Possible clutch issue ?

What year? What Carbs and is it auto transmission?
Dennis
69 OTS

Sounds like maybe the idle is set too low. It should always be put in neutral when you come to a stoplight instead of just putting in the clutch.

My mistake, it is an automatic

Dennis, thank you -it’s a 1968- 4.0 L -Stromberg carbs -automatic transmission

What is engine rpm at idle when fully warmed up in neutral and when in drive, but car is stopped?
Dennis
69 OTS

Bob
Does it run rough at idle when cold (ie choke on) and when fully warmed up?
Dennis
69 OTS with triple SUs

Dennis, it seems to run smoothly with choke on and even after warmed, but when I drive up and down the long circular drive and stop it runs rough until I put in neutral (automatic tranny). Will check the RPM’S when I start her again and see if any changes when she runs rough. Thanks----Bob

Dennis, I got my aluminum radiator and spin-on oil filter adapter from “Cool Cat Express” but there are 3 versions so they will need to see a pic of your block to determine the correct one. 914-234-2079. I believe I use Purolater L30255 or L15317------Bob

What does it idle at in neutral and what idle in drive

Denny

Hi VKid, you have to give enough fuel to this unreliable Carbs,and a tough synchro. not to forget a correct ignition timing . have fun.