I have a Type 4 GCV160 with the automatic choke return. The automatic choke return has worked great until recently. When you start the mower, the choke is supposed to return to the closed position. The past few times I have used it, it has not and I had to manually move it to the closed position. I have been getting some black smoke after starting the mower since this has been happening and so far I think it may be because of the excessive fuel its getting until I can get the choke turned off. Anyway, mower runs fine but I would like some opinions to why my automatic choke return just stopped returning. Thanks for any help.