I have a Dodge Ram 80000 miles on it. 5.2 engine. The check engine light keeps comeing on. I bought one of those code readers and the code that keeps comeing up is P1740. What is it and how do I fix it. Is it okay to continue driving until I do get it fixed. I do not want to do any more damage to it by running it. I bought the truck new in 2000 and this just started about a month ago.