Oil change caused check engine light?

I have 1998 Toyota Camry LE and I usually get the oil change done at every 3500 miles regularly. When I got that done recently, the oil filter started leaking oil right after it came out of shop. I pointed that out and mechanic reinstalled the new filter, just by taking filled filter off and putting new filter on. He did attempt to take filter off while my car was running but obviously he couldn't because it was pressurized inside. Obviously, when he took the first filter out that he had installed with oil change, he said the seal was not even and it was a defective filter. I wish he had checked that before installing it. So I drove off after getting new filter installed and couple of miles down the road, a check engine light came on. I went back and he plugged his OBD handheld and determined that a codes P1130, P1135, P0171B and P0125B are coming up. I knew I had O2 sensor problem (P1135 & P1130) in the past and I had gotten that checked and EGR valve cleaned. I did not have check engine light on when I went in for oil change and now it's coming up within couple miles of driving so obviously something went wrong either during oil change or when the defective filter was installed. Mechanic swears it is a right part#. Now he won't do anything about the check engine light because he says those codes were already there. I got the code cleared and took a ride with one of his mechanics and sure enough the check engine light came back. He keeps saying that it has nothing to do with oil change that they did. Also, when he was running diagnostics, he ran the engine up to 4000 rpm while idle and I know you are not supposed to do that especially on automatic vehicles. Does anybody think that a simple oil change could trigger check engine light to come on? I am certain that the other codes that are coming up now, have something to do with the dignostics that he did when it first came on. I am not trying to get a free ride here and all I am saying is the check engine light wasn't coming on when I went for oil change and now it is so I need some explanation on why this could be happening. I am going to get it checked out somewhere else to determine the cause. HELP ! :