what does a wastegate solenoid do?

[Giz]

Hi......

Thanks for everyones suggestions re: the horrible noise coming from the engine.It actually appears to be the ac compressor. Shame because the air is ice cold.

Now what about the wastegate solenoid? What does it do? Does it need to be replaced immediately?
What does it affect by not working?

Because it sets a code 78 does is this truly the wastegate solenoid or could it actually be another problem?

Thanks for any help.

Angie

[britannic]

The wastegate solenoid is operated by the computer to control the wastegate in the turbo using vacuum.

This gives the designers a lot of latitude in controlling the fuel management map. For example the computer can deliberately back off the boost and fuel levels if a parameter goes out of range and thus protect the engine.

[ 09-02-2003, 03:21 PM: Message edited by: britannic ]

[patrick m.]

code 78 can also be set by a vac leak, check those wonderfull plastic vac tubes for cracks and such, check every inch.

[whatnot]

Are you sure it is the AC compressor? On my trucks, the noise seemed to be coming from the AC compressor but wasn't.
Did you check the vacuum pump to make sure it is working? (it is right below the AC compressor and would give a code 78 if bad)