[57NAPCO]

Gonna get this feller sorted out, one way or another

Originally Posted by arrg

Let's go through these one by one:

1. IAC--did you make sure you removed all the old gasket material/replace the IAC gasket when you changed this? That is a potential vacuum leak. Also, did you have the idle problem before you changed the IAC?

Yes, rubber O ring, yes the problem existed before changing IAC

2. TPS--did this affect your idle in any way? Unless defective, it shouldn't.

Did not

3. Rebuilt TBI--Did you rebuild your throttle body or install a rebuilt unit? The BBC's had two different base footprints over the years. If the base footprint of your throttle body doesn't match the gasket you used and the mounting surface on the intake manifold that could cause a big vacuum leak.

I rebuilt it with a factory kit, no difference.

4. Pulled the EGR--Did you replace the gasket when you reinstalled?

No on the gasket, but no difference after checking it

5. Have you tried capping off each vacuum tap from the throttle body/intake manifold one by one? If you have a leak in one of the lines, doing this will help you find it because with the IAC unplugged as you have it now you would cut off the air and the engine should almost stall.

Not done this yet, I will work on doing that next.

Thanks a bunch for your input.