Car runs crappy after O2 sensor installation

So... I have a 1990 civic hatch, base model with the 1.5L non cali motor. Pretty much stock with the exception of a short ram intake and headers and full 2.25" exhaust and no cat. The O2 sensor was bad so I just put a plug in the bung hole and just lived with the CEL. Ran fine up until I finally got a new O2 sensor and now no CEL but it runs like crap. I've searched and searched for a definitive answer to no avail. Any help is greatly appreciated. Hopefully I gave enough info for an answer but if I missed something just ask. Thanks y'all!
 
No codes and it's stutters real bad at cruising speeds. It "sometimes" will run ok but mostly it's jittery and when I take off from a dead stop, I've almost gotta gun it so I don't kill it. Not sure on the head and block is the D15B2. I'll look at the head in daylight to see

Sorry, it's a D15B1 and I think it's a PM9-3 head

Check again for new CEL codes.

Describe "runs like crap".

Also post the engine head (PM3 or PM8?) and block (D15B2?) codes and the ECU code (PM5?).
I think I misunderstood you when you said codes. I thought you meant what error code. I don't know what ECU code it is. The car is a very base 4 speed if that helps...
 


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Roger roger
Now with all that out of the way, lol, any ideas as to why it's running so bad but not throwing a CEL code?
 


HeX

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Bones, please familiarize yourself with the edit function and avoid multiple back to back posts. I merged your recent ones.

...Pretty much stock with the exception of a short ram intake and headers and full 2.25" exhaust and no cat. The O2 sensor was bad so I just put a plug in the bung hole and just lived with the CEL. Ran fine up until I finally got a new O2 sensor...
What brand is the O2 you installed? If its anything but a Denso or NTK then that may be the issue as older Hondas tend not to work well with any other brand.

Are you sure the headers aren't leaking?

Are you up to date with all the standard maintenance using good quality parts? (Plugs, wires, fuel filter, clean air filter, clean injectors, etc.)

Are you using the correct 87 octane?

...I've searched and searched for a definitive answer to no avail.
You likely didn't search through all the generations info because O2 issues have been covered to great depth in this forum.
 
I apologize for the redundant posts. I was using my cell in the dark and was very aggravated by that time.
I have owned this car about a year. In that year I have replace the water pump and timing belt, starter, alternator, CV axles, plugs, wires, and cap, etc. etc. This morning I disassembled nearly the entire throttle body assembly and cleaned every sensor except the TPS. I even pulled the injector(s) and gave them a good cleaning. I pulled the PCV valve an cleaned it. On the headers, the PO had put a short drilled out non-fowler between the O2 sensor and header and I removed it (just grasping at straws by this point) and re-installed the O2 sensor. Put everything back together, fired it up and drove to work and did not have one hiccup. It ran beautifully. So not sure if it was one of those or a combination of a couple but it is now resolved... I hope. Thank you for the help and I'll do a deeper search next time. I didn't think to look into the other generations (hindsight is 20/20)
 


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