help
 

Ok I have trouble with my car idling low even after i have being driving it for a long time it would idle so low it would not move even when i floor it , it would stay like that for about 5 mins then everything would be fine but today i got a check engine light that came on then went away after i steped on the gas
I did replace the ovp did a full tune up so far
I hear this could be related to an egr valve well on my 89 300e i dont see any egr valve on the manifold
Is there anyway i could check the codes on an 89 300 e
Any suggestion would be greatly appreciated thanks