As I post gas in Tijuana is running $3.80 to $3.90 per gallon depending on the exchange rate and the station's price.  That is a welcome relief from the $5.00+ per gallon price in San Diego due to Russia invading Ukraine on top on the inflationary increase under Biden.  (From under $3.00 per gallon the day Biden took office to over $4.00 per gallon when Russia invaded Ukraine.)  

When the PEMEX gas stations were sold to US companies there was a provision in the sale that limits how quickly gas prices can be increased.  So if they go up in Mexico they will go up slowly.  Absent price gouging by PEMEX and/or the US companies that bought the PEMEX gas stations gasoline prices shouldn't go up due to Russia invading Ukraine because Mexico is a petroleum exporter, not importer.