Check engine trouble? 3 codes?

Hello! I have a 1995 nissan 200sx SER. I have owned a few 200sx's and this is the first one that has had more than one trouble code kicked off at once. I had autozone run the trouble codes and found that it was the bank 1 O2 sensor in the exhaust manifold, and the EGR valve code, as well as the Knock sensor code. I have been noticing poor gas mileage, which is about 25 mpg average or less. I'm used to 30-35 mpg. It also has trouble starting when left unrun for a few days. It also accelerates jerky when I shift on a cold engine. It feels as if there is a point were it is sluggish, then becomes normal. This is like before it hits its torque band above 3, but much more exagerated. This dissappears when it is warmed up. Is this normal? Maybe needs a tune up?
I was wondering if one problem can trigger another code. For instance, the o2 causing the EGR and Knock sensor. Would replacing the o2 sensor help this? Any thoughts? Thanks guys!

Hello! I have a 1995 nissan 200sx SER. I have owned a few 200sx's and this is the first one that has had more than one trouble code kicked off at once. I had autozone run the trouble codes and found that it was the bank 1 O2 sensor in the exhaust manifold, and the EGR valve code, as well as the Knock sensor code. I have been noticing poor gas mileage, which is about 25 mpg average or less. I'm used to 30-35 mpg. It also has trouble starting when left unrun for a few days. It also accelerates jerky when I shift on a cold engine. It feels as if there is a point were it is sluggish, then becomes normal. This is like before it hits its torque band above 3, but much more exagerated. This dissappears when it is warmed up. Is this normal? Maybe needs a tune up?
I was wondering if one problem can trigger another code. For instance, the o2 causing the EGR and Knock sensor. Would replacing the o2 sensor help this? Any thoughts? Thanks guys!
i have those EXACT same problems, however mines a 96 200sx se a/t... ever find out what was up?

i have those EXACT same problems, however mines a 96 200sx se a/t... ever find out what was up?


Yes, I changed the bank 1 02 sensor. I then left the battery unplugged for 24 hours. Once reinstalled, I noticed the check engine light was still on. So I checked the engine, and it was still in there..... lol.....

Anyways, after 200 miles or so, the light went out and no longer had trouble starting the car. I couldn't tell you what the gas mileage improvement was because I sold that car 3 days after the light disappeared.

If still poor mileage, I was going to have my EGR cleaned, but not replaced as they don't really need replacement, just cleaned (says my mechanic buddy).
I'm sure a tune up could help as well!
Hopefully you have success with resolving this issue with your vehicle!
any questions ask!