I have a 1998 ford ranger, check engine is on,had it scan, codes PO452 & PO453... How do I fix this, it runs fine...

 

If you were getting either one or the other of those codes it could indicate a problem in certain areas. But,, since you are getting both of them at the same time the fuel tank pressure sensor is not sending rational info to the computer. If you checked all the connections back at the fuel tank, there is a pretty good chance the pressure sensor is defective. Loose or poor connections can do this too.

 

I replace the fuel cap today, so far no check engine light......

 

I had a check engine light that said both O2 sensors were bad. I did the new gas cap, that lasted a week and the light came back. I put a new something or an other and checked all the vacuum lines and the light came back on a week latter. I put a new gas filter on and the lights been gone for months now. I have a 98. good luck