Car wont idle now!

[All4rocks]

New 68 Coronet build. 426 hemi with 2 Edelbrock carbs. Engine ran and idles in shop . Took it out for its first test drive and ran good for first 5 minutes then died in my driveway. If i pump the accelerator it fires right up then dies. It will not idle on its own. Once started i have to keep "blipping" the throttle to keep it running if i dont it dies. Checked fuel pump lots of fuel going in to bowls. Both carbs squirting fuel in engine when throttle opened. Any ideas?

 

[6PKRTSE]

If you have fuel. It sounds electrically related. Coil cutting out. Check main harness at the bulkhead. My Charger would shut off once in a while until I diagnosed it being a bad harness at the bulkhead connector.

 

[Don Frelier]

Sounds like it's too lean when it gets warm.
Richen the idle screws then possibly change the metering rods to a smaller first step rod.

 

[threewood]

Maybe the distributor is loose and timing was retarded?

 

[Don Frelier]

Or just the idle speed screw needs adjustment. Could have been on the fast idle cam until warm.

 

[65-440]

Definitely sounds carb related. Ignition wouldn't come back on from blipping the throttle !

 

[6PKRTSE]

Check the fuel pump push rod also. I had one mushroom out on me before. Car would stay running if you blipped the throttle from squirter shooting fuel but would not run/idle on it's own. Swapped the pushrod still running today.

 

[65-440]

Check the fuel pump push rod also. I had one mushroom out on me before. Car would stay running if you blipped the throttle from squirter shooting fuel but would not run/idle on it's own. Swapped the pushrod still running today.

Forgot about that one ! But he did say he had good fuel flow into the bowls ....

 

[beanhead]

I've had coils go bad and do that same exact thing. If you have a spare, swap it just to rule it out. If it's squirting fuel into the engine and it ran in the shop, I would think something would have had to have been drastically altered for it to not stay running at all now..

 

[BeepBeepRR]

Give me the engine, swap in a 4 banger and call it a day. I will take on your burden. On a serious note.. Have you checked for vacuum leaks?

 

[33 IMP]

Sounds like a big vacuum leak to me too. Big hose or plug fell off of carb base?

 

[Johnpat]

Check for vacuum leak,that would cause it to run
To lean unless pumping gas to overcome.
Do you have a vacuum tree? start there and
check all connections.

 

[BeepBeepRR]

Make sure there is a plug in the rear of the carb base. In my case I have the PCV plugged into it but both of yours should have atleast the front one should be plugged off.

 

[All4rocks]

checked all vacuum lines and fittings all are good

 

[All4rocks]

Problem fixed! Apparently the idle screw had backed itself off (dont know why the spring did not hold it). Fixed the spring and turned in the screw and Waalaa! We got idle.

 

[Johnpat]

Simple things cause great anxiety

 

[All4rocks]

Thanks for all the help! i was expecting something a little more complicated.