[69CATFE]

Once really, really, really warm the Cougar is actually running better than ever. But unless it warms up for an excessively long period of time (maybe 20 minutes), it will quit when idling and in gear. In park or neutral it is fine. This is a new issue - previously I only needed like 5 minutes.

The car is a '69 with a 390, Holley Carb w/electric choke, c6 trans. The engine is to the best of my knowledge stock. Vacuum checks good (steady at about 16") and idle timing is roughly 15°BTC

So I guess my questions would be:
1. How long should the choke stay closed?
2. How long should the fast idle cam stay "on?"
3. Someone suggested that my thermostat could be stuck open causing the engine to "cool" when not necessary. Seems logical to me - thoughts?
4. Anything I missed? Should I be able to tell anything by the temperature gauge?

And just for perfect clarity - after the car has been running for a while - it runs fine. I guess I have no proof that it is temperature related....

 

[1969XR7Vert]

Your #3 is what I immediately thought when I read the title of your thread, does the temp gauge take a long time to come up to "normal" operating temperature range? If yes, replace thermostat.

#1 - A few minutes tops, the flapper should start to show signs of movement - opening within a minute or two after starting (in the summer anyway, winter longer).

#3 - Forever or until you tap the gas after the choke has opened, whichever comes first :buck:

Hope this helps.

Regards,

Bob

 

[doctordesoto]

you could have developed a small vac leak but i'd go with the thermostat
doctordesoto

 

[69CATFE]

Ok - Thermostat will happen first! Do I go with the stock temperature or something different? (I will need to look up the stock temperature when I get home).

 

[towcat]

180 deg. should work fine.

 

[69CATFE]

It was the thermostat....

 

[ClawIt]

I hope its your thermostat. I had a 390 do the same thing, would not idle until about 10 minutes, sometimes 20 in the winter. Problem was worn out rings.

 

[Bad69cat]

Some girls are just that way - ya gotta patient man! Warm 'em up an you get what you want! Hows the choke wired? Hopefully off the "STA" terminal on the alt.....be sure it is actually working properly too. You may need to do some adjusting on the cold idle cam on the carb as well....once you know the choke is working right.

 

[1969XR7Vert]

It was the thermostat....

(Blowing on fist and rubbing sleeve with fist) Yep, I knew that would be it... :buck:

 

[69CATFE]

Maybe I spoke too soon. Don't get me wrong here - the thermostat was bad. But that might not be all there is to the story.

I think a compression test is in order - I haven't done one on this car (or ever) so just having that bit of info will be handy.
It is off to Harbor Freight for a compression tester....

I'm also going to try a new cap, rotor, and points set (the points look a little gnarly).

As a side note: I am pretty confident that the choke & carb are fine. I bought a new Holley a year ago and haven't F&$ked with anything. The choke is appropiately wired (not to the STA terminal - but directly to the battery VIA a relay to a switched source).

 

[69CATFE]

Hmmmm. Started pulling plugs. One looks brand spankin new. I think this is a bad sign.....