My 1966 Mustang with the 200 c.i. engine and C-4 automatic has a rough idle problem that is baffling me.
With the engine at operating temp. and idle set to 700 rpm in park,the engine idles fine.
When trans is placed in drive,rpm drops to 600 and stays good for about 5 seconds.
The idle then drops to 300 rpm and acts like it's running on 2 cylinders. Very rough.
When placed back in neutral,idle returns to 600 and runs fine. Placed back in drive...idles for 5 to 10 seconds..then drops back to 300 rpm and rough.
This will happen consistently,every time I tried it, for 5 times. When idle is raised to 850 rpm in park,then shifted into drive..idle drops to 700 rpm and stays there. No rough idle occurs at this setting.
I don't like running the engine this fast,fearing transmission damage.
Timing is set at the top notch..14 degrees.?? Runs rougher at 10-12 degrees. The engine has a new camshaft and the trans was rebuilt. All totally stock.
Ignition is Petronix with all new parts on distributor. Carburetor is stock Holley 1 barrel
Also there is NO vacuum advance at idle. Is this normal for this engine? Tested advance can with vac pump and it works.This is my first Ford and I'm not familiar with how this system operates.
I'm guessing I have a carburetor problem. The carburetor is not original Ford. It's a Holley model 1940. Where is a good source for carb rebuild parts and manuals for same.
Has anyone else had this problem?
With the engine at operating temp. and idle set to 700 rpm in park,the engine idles fine.
When trans is placed in drive,rpm drops to 600 and stays good for about 5 seconds.
The idle then drops to 300 rpm and acts like it's running on 2 cylinders. Very rough.
When placed back in neutral,idle returns to 600 and runs fine. Placed back in drive...idles for 5 to 10 seconds..then drops back to 300 rpm and rough.
This will happen consistently,every time I tried it, for 5 times. When idle is raised to 850 rpm in park,then shifted into drive..idle drops to 700 rpm and stays there. No rough idle occurs at this setting.
I don't like running the engine this fast,fearing transmission damage.
Timing is set at the top notch..14 degrees.?? Runs rougher at 10-12 degrees. The engine has a new camshaft and the trans was rebuilt. All totally stock.
Ignition is Petronix with all new parts on distributor. Carburetor is stock Holley 1 barrel
Also there is NO vacuum advance at idle. Is this normal for this engine? Tested advance can with vac pump and it works.This is my first Ford and I'm not familiar with how this system operates.
I'm guessing I have a carburetor problem. The carburetor is not original Ford. It's a Holley model 1940. Where is a good source for carb rebuild parts and manuals for same.
Has anyone else had this problem?