95 Dodge Neon w/ codes P0134, P0401, U3FFF

I have a 1995 Dodge Neon w/ a 5-speed manual transmission that I drive to and from work. My check engine light came on and I got three codes from it:
P0134- O2 Sensor CKT No Activity (bank 1, sensor 1)
P0401- EGR Flow insufficient
U3FFF- No DTC Definition Found

The problem I am having occurs about 30 min into driving the car, from a cold start. It loses acceleration(in second, third, fourth and fifth gears), sputters and if I pull over, the RPMs drop below 600 and the car starts to sputter, like it's going to just stall and die. If I turn it off, and back on, the RPMs rev quite high (up to 3500 in some cases). I am usually at my destination in 30-60 min and after it sits in the parking lot, it starts up fine, sounds normal, doesn't have any problems until about 30 min into my drive home...

I would like to repair/replace any parts myself if possible, but if not, would like to know which code might be causing my problems so I can get it in and out of the shop quickly on my days off. Any help would be greatly appreciated.

"Snowz" <none.TakeThisOut@000.com> wrote in message
news:977612_ff91a8d38631e658778e013243b46880@autoboardz.com...
> I have a 1995 Dodge Neon w/ a 5-speed manual transmission that I drive
> to and from work. My check engine light came on and I got three codes
> from it:
> P0134- O2 Sensor CKT No Activity (bank 1, sensor 1)
> P0401- EGR Flow insufficient
> U3FFF- No DTC Definition Found
>
> The problem I am having occurs about 30 min into driving the car, from
> a cold start. It loses acceleration(in second, third, fourth and fifth
> gears), sputters and if I pull over, the RPMs drop below 600 and the
> car starts to sputter, like it's going to just stall and die. If I
> turn it off, and back on, the RPMs rev quite high (up to 3500 in some
> cases). I am usually at my destination in 30-60 min and after it sits
> in the parking lot, it starts up fine, sounds normal, doesn't have any
> problems until about 30 min into my drive home...
>
> I would like to repair/replace any parts myself if possible, but if
> not, would like to know which code might be causing my problems so I
> can get it in and out of the shop quickly on my days off. Any help
> would be greatly appreciated.
>
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>
When did you have the last tune up done with a good set of plug wires, The
02 sensor code could cause a surge while driving and if it shorts out could
cause other problems as well.
The proper way to diagnosis this would be to have a scan tool connected and
systems monitored.

Glenn Beasley
Chrysler Tech