A District of Columbia hearing examiner assigned to a case involving the firing of a city prosecutor in connection with the cancellation of city traffic tickets said yesterday he would excuse himself from the case in the wake of disclosures that 32 tickets issued to his own car had been canceled.

During a brief hearing yesterday, Michael H. Sindler said in a prepared statement that he was certain that he could review the matter impartially but that he had "grave doubts" that others would think the process was fair if he remained on the case.

Sindler said he was deeply hurt by the D. C. corporation counsel's request that the step aside, an action that he said had the effect of "questioning my integrity."

Sindler, an appeals and grievance examiner, accumulated the tickets during a 15-month period in 1976 and 1977 while he was chief of the public Vehicles of Division of the Department of Transportation. Sindler also is a former assistant D. C. corporation counsel.

Sindler contends that most of the tickets were issued by overzealous police cadets, that all the tickets were issued while he was on the job and were cancelled for "good cause."

The city's personnel director assigned Sindler to hear the case of assistant corporation cousel Victor O. Frazer, who was fired last APril, in the after-math of a crackdown on traffic ticket cancellations.

Then D. C. Corporation Counsel John R. Risher Jr. fired Frazer when he refused to pay $1,180 for tickets issued to him or to other persons that Risher contended were improperly canceled. Frazer consistently has contended that he acted within his discretion in the matter.

Last week, after a computer check revealed that the 32 tickets issued to Sindler had been canceled, the corporation counsel's office asked him to remove himself from Frazer's case to "avoid the appearance of impropriety," No actual charges of improper conduct by Sindler have been made.