High Idle in Park 1964 Thunderbird

[Dillon Anderson]

I have a 64 thunderbird and it idles high when it is in park. When I shift to reverse or into drive it seems to idle fine, but when I shift it to park the RPM's rise and it idle very high. I thought it might be a vacuum leak but then it should idle high in drive and reverse too right?

 

[DannyInNJ]

When you start it cold, do you later hear it "kick down" to a lower idle? To me it sounds like your choke is the culprit. You should have a distinct "cold" (fast) and "warm" or "hot" idle (lower) idle. Since I noticed you didn't mention if the choke is working, I'm guessing she's not and the carb is staying in "cold" idle.

 

[Ezdarryl8]

I have a 64 thunderbird and it idles high when it is in park. When I shift to reverse or into drive it seems to idle fine, but when I shift it to park the RPM's rise and it idle very high. I thought it might be a vacuum leak but then it should idle high in drive and reverse too right?

I'm sure your aware if u have 390 fe with 4bbl. You have a cold idle adjustment and the hot idle adjustment, can't be done correctly unless you run motor for about 30 min. Look in your repair manuel it will hive you step by step instructions