There are two ways you as a US expat can avoid penalties from the IRS:
File your US tax return with MyExpatTaxes or request an extension by June 15th every yearMake up any years of missed filings through the Streamlined Procedure
If you skip out on filing US taxes from abroad, the IRS could collect old tax info on you and approximate how much tax money you owe. Therefore, it is possible you could pay more than you need to. Plus you could get penalized from the IRS for faliure to file, faliure to pay or owning a dishonored check.
Learn more on how not to get in trouble with the IRS.