Trouble shooting 74 L-Jet, Where do I start Options

[Levi]

My 74 1.8 L-Jet is giving me trouble, At start up, engine cold, it will idle rough (400-500 rpm) and seems to be loading up?, after 3 or 4 minutes the rough idle goes away and it will idle at 900 rpm's, but if I ease into the throttle it cuts out around 2800-3500 rpms, but I can rev it to red line. after driving it 2 or 3 miles it seems to clean out and runs great, however it will from time to time die when I have the clutch in while stopping.

Where should I start looking

[Joe.D]

Thanks for the ideas so far guys,

Its all tuned, do you guys really think it could be a vacuum leak, (IMG:style_emoticons/default/confused24.gif) I ask that because once its at running temp. it runs like a top, its smooth thru the rpm range and pulls hard.

I will start checking/replacing the hoses tho, they are braided and look like they might still be original.

If it runs well after it warms up, focus on the cold run components. My first suspect would be the Aux Air Control. Check to see that its open when cold. If its stuck closed, cold idle would be very low, since the engine isn't getting the extra air added to the richer warm up mixture.

It isn't easy to check without removing it, but with a small light and one of those dentist mirrors, you can manage to look into/through it. Its located just behind the oil fill tower. Sorry, can't post a picture of it right now.

Joe