pierburg 175 cd
 

The only way the car will run right now is with full throttle if you let up it dies, and at full throttle it is just barly running is there a possibliity the piston is installed backwerds, I noticed there is holes in the piston on one side???

No matter what carb you have, basic instinct tells me to look for a vacuum leak.
I would like to recommend you post this question in the Vintage section as well. Lots of folks who like to torture themselves with carbs there. ;)

The holes go toward the intake. Unless modified they should not be able to be put in wrong. I think, been a while.

The carb is also very susceptible to poor mixture settings. The electric solenoid on the bottom is the mixture adjustment device. it raises or lowers the main jet.

Hi

Steve - The electric solenoid below is the fuel cutoff to prevent over running.

Ken - Steve is right about the piston. The rubber diaphram allows only one way to fit the piston as there is a notch where it fits the carb body. Perhaps more history on the carb?

Oreo

The electric solenoid IS THE MIXTURE DEVICE! It also is the fuel shut off solenoid. If you look at it, it has two 19mm jam nuts to lock it where ever the mixture is right. By turning it in or out the height of the main jet is raised or lowered changing the mixture for a given rise in the airflow piston.

Apparently there is more to this thread somewhere else. More info would help. From the info here I sort of doubt that the solenoid could be that far out of adjustment and the anti dieseling portion of the solenoid only picks up for 6 seconds after the key is in the off position. I would check the position of the needle in the piston. The little plastic ring should be flush with the bottom of the piston. Also a big problem with this carb is severe cracking of the rubber base mount. If you provide more detailed info, I can provide a better diagnosis. You may even have a brake booster hose disconnected.
Peter