Got the code 45 squared away, but I don't think I got it squared away correctly. I switched ports on the EGR vacuum line going into the computer itself and it smoothed it right up, now the truck is acting like it has an awful vacuum leak. It's also giving me a code 42 and a code 43 on occasion. I pulled both these up and looked at what they meant, but they are NO help. Can anyone hear give me any advice. I have to have the truck back today. The truck idles fine and runs good, till I start down the road, then it acts like it is loading up something fierce. It REAL tough to get up to 55 mph. PLEASE HELP!!! Thanks BTW, this is a bone stock 89. The only changes made in the motor department are a .30 over bore and a K&N filter.