Car running poor

[murray1]

My car is a 97 Talon NT. Recently it has been idling rough and hesitating when I give it gas. About a week ago my upstream o2 sensor finally went bad enough to throw CEL. I took it to a mechanic he pulled a code telling me upstream o2 sensor was no good. It started idling worse and hesitating and getting worse noticeably everyday. I learned about keydance and did it yesterday and got code for upstream o2 sensor(21), and misfire?(43).

Today I bought an o2 sensor and installed it. I unhooked battery to clear CEL. Once I started car up I noticed that it idled noticeably better and that its hesitation was not as jerky. Something is still wrong though. After driving for just 10 minutes or so CEL came back on. I did keydance got code 43, misfire again? It still doesn't idle great, only a little lumpy though, and it always hesitates if I give it lots of gas, doesn't matter what gear or rpm. You can feel it and hear it when it does this. It isn't jerky or anything just wont go. Any ideas on what it could be or what I should check/do.

 

[95 'clipse RS]

have you checked plugs, wires, ign coil, MAP sensor, etc? a misfire can be caused from numerous things. id say youre best bet would be to check everything out that could cause a misfire. but probably the first thing you should check is the timing, being that these are interference engines. you dont wanna take any chances on that. IMO

 

[Shadow98]

IMO the first 2 things to check would be plugs followed by coil pack.

 

[XMasta19]

You very well could have fouled out your plugs running long enough on a dead o2 sensor. The car was excessily rich I'm sure, and probably never even made it into closed loop operation.

 

[murray1]

You very well could have fouled out your plugs running long enough on a dead o2 sensor. The car was excessily rich I'm sure, and probably never even made it into closed loop operation.

I pulled all my plugs and none of them have signs of running rich, if anything they look like they were slightly hot or lean. One of them I could see the electrode was worn so I am going to replace them.

 

[murray1]

have you checked plugs, wires, ign coil, MAP sensor, etc? a misfire can be caused from numerous things. id say youre best bet would be to check everything out that could cause a misfire. but probably the first thing you should check is the timing, being that these are interference engines. you dont wanna take any chances on that. IMO

As stated above I checked my plugs, my wires look to be in good shape, I am not sure how to check an ignition coil, map sensor. My timing belt and everything look to be in good shape and I would need a timing light to check correct?

 

[Defiant]

Looking at plugs doesn't tell you shit. Replace them, and the ignition wires.

Once cleared, the ECU has to learn the car's current condition again. It can take two weeks. Give it fresh, properly-gapped plugs and nice new wires to tune itself to.

 

[murray1]

Hey thanks guys, it was just my spark plugs along with my o2 sensor. I am pretty sure plugs weren't fouled they were just worn. I bought 4 new ones and gapped them to .045 and then thought I would check my old ones gap because I could tell by looking that the one for sure was worn. I didn't have one under 0.055 and the bad one was 0.08 . I guess that would probably provide some misfire/hesitation.