urgent injectors help

[RiversideS13]

ok, my 91 ka24de runs rich. it idles fine and drive smooth, but just making some black smokes and smell like fuels. I already replaced O2 sensor, MAF sensor, coolant temperature sensor, spark plugs, fuel filter, air filter and it made some improvement. however, it didnt complete fix the problem. (before i replace those, it was making more black smokes and back fires all the time).

so my friend suggeted it might be the injectors that is the problem since it has 196k miles and the injectors might still be the original one.

upon searching, i found this http://www.jcwhitney.com/autoparts/Product/tf-VehicleBrowse/s-10101/Pr-p_Product.CATENTRY_ID:2009413/showCustom-0/p-2009413/N-200729004+111+1991+600010351/c-10101
and they are in great prices, but i dont know which one to order. I need help urgently since it has free shipping and it ends today. I did my math and i found 17lb might the one i need? or should i get 21lb just in case?

i have a 91 ka24de NA with k&N filter and RSR exmag

thanks

[Sil-Abc]

did u run any fuel injector cleaner? are u sure that all 4 plugs are firing? probably ur injector could be stuck open? just tryin to give u some options before u do this :D

[ranisron]

I don't know, I would pay a visit to the junkyard - that's where I got my used injectors... I don't know if this would work for you. do you run rich across the entire rpm band?

[aznpoopy]

if you had an injector stuck open your car would flood to shit very quickly

ask me how i know ;)

check your oil and see if its diluted with gasoline.

[ledzeppelin240]

Is the car hard to start when it is warm? Check your oil for gasoline as mentioned and also whats your O2 sensor voltage output, check that to see if it is correct. A fuel injector could be stuck open, you could have a missfire in a cylinder(s). If there is a missfire in 1 cylinder the O2 sensor will read lean so then the ecu thinks it needs more fuel.