2003 Hyundai elantra gt problem losing power after 40 miles, engine warning light on

Just got my first car. A used 2003 Hyundai elantra GT with 79000 miles an
I have taken it over 40 miles on a drive twice and it has started to los
power at about that point. First time it did it I was close to home an
made it ok. No engine warning light came on at that time. 2 weeks later o
my next drive over 40 miles, the car did the same thing. This time I was 4
miles away from my house. I let the car sit for about 15 minutes and wa
able to make it home ok. This time, the engine warning light came on an
we went and got some Diagnostic codes pulled and they were P0705
Transmission Range Sensor Circuit Malfunction - PRNDL input ) and P1166
heated Oxygen sensor 1, bank 1, at control limit ). Engine warning ligh
has now gone out. I don't want to drive this car over 40 miles or so no
because of what has happened. What are my next steps? Thanks for any help

 

Are you comfortable working on cars? If not (and it seems you may not be),
then your best bet is to take your car and your codes to a dealer or a
mechanic you trust. These are fairly common problems and you should not be
facing big charges.

 

You'll likely need a range switch to cure the P0705, but the P1166 can be
little trickier. P1166 simply indicates that either the oxygen senso
reading is way out of whack, or the injector on-time required to achiev
proper mixture is way out of whack. While the upstream oxygen sensor is
frequent culprit, the 40 miles scenario makes me wonder if you have
problem with the fuel pump. Presuming you're not going to be able t
diagnose the P1166 issue yourself, you should take the car to be checked