I have a 1998 Honda Civic DX. It has 198 K miles on it. I love that car but when I bought it in September of last year 2013. The check engine light was on. It came back with a P0420 code. I'M getting the cat. converter replaced. I also basically had the whole engine rebuilt. Now the other day when I went to start it and drive home the speedometer was stuck at 20 MPH and. Would bounce up and down. I disconnected the VSS and it still did this. I took it to auto zone and had them scan it to see if anything else would cause this. and it came up with a P0705 AKA Short in transmission range switch. is a code thats being thrown as well as a P0430 Catalyst system efficiency below threshold bank 2 & the P0420 Catalyst system efficiency below threshold bank 1. my main question is would the short in the transmission range switch cause my speedometer to malfunction? Also I think my heater core is broke. Any help would be greatly appreciated thanks also I noticed that it's losing power when I drove back from Baltimore MD i almost had to keep my foot to the floor to keep it at about 80 MPH on the interstate would this be due to the cat converter not causing the motor to up-shift? thanks again :-) Hear is video of what my Speed O is doing.

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