A Coronation Street star was found guilty of drink driving yesterday after magistrates dismissed his claim that a series of burps invalidated his breath tests.

Simon Gregson, who plays Steve McDonald in the ITV1 soap, was pulled over by a police officer who spotted his Jaguar XKR driving the wrong way down a one-way street in Prestbury, Cheshire, last May.

A roadside breath test gave a positive result and two further breath tests at Wilmslow police station revealed a reading of 60mg of alcohol per 100ml of breath - nearly twice the legal limit of 35mg/100ml.

The 31-year-old actor, a regular in Coronation Street for 15 years, could face six months in jail and lose his licence for a year. Sentencing was adjourned until next month.

Gwyn Lewis, defending, argued before magistrates in Macclesfield that the breathaliser evidence was inadmissible because the police officer who administered the latter two tests failed to ask a vital question.

The officer, Sergeant Jeremy Taylor, admitted forgetting to ask Gregson 'Have you brought anything up from your stomach?' immediately after the test.

He only asked the question around 45 minutes later, while Gregson was in a cell.

The question should be asked in case stomach acid is in the mouth - which can give a misleadingly high alcohol reading.

The court heard that Gregson, who appeared under his real name of Simon Gregory, has a longstanding medical condition, reflux oesophagitis, which causes stomach acid to flow back into the throat.

He told the court that he had belched several times during the tests, but that Sgt Taylor failed to notice.

He said: "I remember I was sat to the officer's left-hand side and I was burping and bringing up acid into my throat, which I just swallowed back down. It was like five, six, seven times. I remember putting my hand up to my mouth."

Gregson said he had suffered from the illness since 1998 and had become so used to it that he did not think to mention it during his arrest, even when asked if he suffered any medical complaints.

Gregson said that when he was eventually asked whether he had "brought anything up" from his stomach, he assumed the officer was asking if he had vomited and so replied 'no'.

The bench of three lay magistrates rejected Gregson's case and found him guilty of drink driving.

Chairman Alan Edgeworth said: "We found the question (of whether he had brought anything up from his stomach) is not a statutory requirement and accordingly found the failure to ask it at the appropriate time does not invalidate the whole procedure.

"We do not accept the evidence of the defendant that he was repeatedly burping and bringing up stomach acid."