88' Camaro, 5 speed, 305 TB.

For a couple of weeks now the car has become extremely jerky through all gears after a couple of minutes of driving from a cold start. The jerking is there right away from a hot start.
The idle is slightly rougher than it should be, but not too bad. The main problem is regular driving, both around town and cruising on the freeway.
It's especially bad if the AC is on.
The only way I seem to be able to get rid of the jerking when it starts is to leave the AC off and go WOT for a sec, then the jerking will tend to stop for a minute or 2, but not always.
I am getting a SES most of the time, and also noticed a lot of black on the rear trim above the tailpipes..........................carbon???
I am going to head to Autozone after work tonight if the SES light comes on and have them scan it.

From what I am, and have been reading, it appears to be a bad O2 sensor.
Any thoughts greatly appreciated, as if the SES does not come on so they can scan it, I was going to buy an O2 sensor anyway and throw it on.
I would just like to know if I am on the right track, or any other possibilities.

I have a bad EGR valve on my 94' Z28, and I ruled this out for the 88' 305 as the symptoms are not the same.

 

The best thing to do is find out why the SES light is coming on by having it scanned or doing it yourself. Just because the SES light isn't on, they can still scan it for codes. The computer stores codes if the SES light ever comes on and stores it in its "memory" for a while, in layman's terms. You can check the light yourself, though, here's how:

Make sure the car is off, get under the driver's side floorboard area, pull the fuse cover down and look to the right of the fuse block, and you should see a rectangular looking device with 12 holes in it that looks like this:

OOOOOO
OOOOOO

Insert a U-shaped paper clip or small length of wire in the top 2 right hand side holes. Turn the ignition key to KOEO (key on, engine off) and watch the SES light. It should flash once, pause, then flash twice quickly. That's a code 12, meaning it's working correctly. It will flash code 12 three times, and then the rest of the codes will be flashed 3 times each and then it will flash code 12 again. For example, if the SES light flashes four times quickly, pauses, then flashes three times quickly, that's a code 43. Simple, huh? Once you have the codes, post them and I or someone else can tell you what they mean. All of this info can be found in a Haynes or Chiltons manual, too.

 

OK!
Thnx.

The Autozone near me told me they can only scan while the light is on.
I did think this was wrong, but you argue with them and it gets you nowhere!

 

Paperclip worked.
Thnx much for that.

Threw a code 13 and 44 at me.

Anyone interpret those please I would be very grateful!

 

Found the codes in another thread after a search.
Looks like buying the O2 sensor otw home today was a good idea!

 

Unbelievable . The paperclip method or any scanner can scan for current and soft codes which have been tripped and not being tripped currently.