shhwing

I have noticed problems ever since my engine was rebuilt. The problems didnt exist before the motor was removed and replace. One problem is that occationally when crusing in 6th gear, A/C on, while flooring the gas pedal...the upper mode A/C door seem to move preventing air from blowing out of the dash vents. (A total loss of engine vacuum?) The air sounds as if it is blowing through the lower vents, but definaltely stops moving air through the upper vents. As soon as I let off of the pedal, the air returns through the upper vents.

This seems to be a vacuum problem, maybe something wasnt re-connected correctly...or possible something to do with the cam that was installed preventing enough vacuum from being generated at full throttle. I know that when I start the engine, I have to wait until it builds a vacuum before it will idle smoothly. At the time this happens, the A/C will only then begin blowing air through the upper vents on the dash.

My cruse control also is not working since the rebuild. Any chance these are all related? A/C, idle, and cruse?

jkichline

iTrader: (1)

its hard to say exactly what you should be looking for. I would start looking at all your vacuum lines. See if you can hear anything at idle. pull the throttle cable and see if you can hear anything as your timing advances.

With your cruise not working its gotta be a vacuum leak. Start looking around your cruise control area for leaks.

Travis99LS1

iTrader: (2)

There is a vacuum reservoir that prevents your mode doors from switching when there is a loss of vacuum. There is no "vacuum" in the intake manifold when your at WOT...its just atmospheric pressure..You could try and get a diagram of the vacuum lines running to the mode door and check to make sure there all in the right spot, and that the reservoir is installed properly.

joshp14

iTrader: (5)

There isnt any vacuum lines that allow the cruise to be inop. Its all electronic in these cars (LS1's).