i posted a few other threads and never got the right answer. i really need this thing fixed, its been over a month, and i have to drive it to school daily. For some reason the throttle is really touchy in 1st and 2nd gear and alittle bit in 3rd. i have to be really really smooth onto the gas or it will start bucking really bad. also if i just floor it it runs good. my dad says he thinks its supposed to be like that but idk? and then after driving it for more than 5 minutes the check engine light comes on and its saying code 1 o2 sensor. i just replaced the o2 sensor and its still doing this. when the check engine light comes on it does the bucking WAY worse than usual. and it idles real ruff around 200-500 rpm

 

maybe you should test your o2 sensor wiring already like suggested in your other thread. I have a feeling you're gonna keep coming back with more questions untill you take the initiative to start troubleshooting this thing yourself. Its simple invest in a digital multimeter and a helm manual (with the wiring diagrams) for your motor, and one for the car (handy but not necessary for this) , and start following the troubleshooting procedures for the o2 sensor and wiring.

and one more thing we aren't gonna have the "right answer" for you due to the fact that the previous owner of your car did a hackjob of a swap, so we dont know what he did or didn't do, you're gonna have to search for the route of your problem yourself we can only help to point you in the right direction.

 

what kind of gas milage are you getting?

 

when you say bucking do u mean it jolts or kicks back and forth????....if this is right check your timing and if thats it u might need a new timing belt because if it is worn it can and will skip teeth...when u floor it its keeping tention on the belt but if your just cruzin its free to move and flap around on the pullys

 

i followed the o2 sensor wire and its connected to the ecu where it should be. gas mileage isnt too bad

 

so you tested the continuity and voltage, or do you mean a visual check? because there is a huge difference.

 

not sure how to explain it but if i get on the gas smooth it goes smooth, but if i just push the gas in about halfway it like tries to go and let off and go and let off and keeps doing that till i let off and let the rpms drop real low and get on it smooth again or shift up and get on it smooth.

 

no i just followed it to see if it went back to the ecu where it should to make sure it was even hooked up.

 

okay, then follow the advice I gave in my first post. good luck

 

got my bro to take this on the way home from school, you might have to turn your volume up to hear it, hope this helps
http://s98.photobucket.com/albums/l2...2091510-01.flv

 

tps or dizzy or timing, but i doubt it is the timing, are all your grounds hooked up?

 

yes they are, and theres like 10 of them

 

ive been thinking its the tps, but that wouldnt cause the CEL for o2 sensor would it? but then again maybe its more than one thing

 

Here is the factory service manual for troubleshooting the o2 sensor.

I have attached also the page for inspecting the Fuel Pressure Regulator. Hope this helps.

If you don't have a multimeter. I bought one from sears a craftman brand for 14.99 and it works great. Having one of these has helped me out countless times.

 

well for now i just checked the fpr by taking the vacuum hose off and pinching return hose. both worked and raised the pressure to 40. i just noticed my car now idles at 30 psi and it use to idle at 35psi

 

anyone? and does it matter that the fuel filter is just hanging?

 

okay i turned the key on the on position to see if the pressure was going up right away and it says 30psi, and what im pretty sure is the fuel filter hanging i pulled up on it and the pressure went up to 36psi.could this be the problem?
http://i98.photobucket.com/albums/l2...2091736-00.jpg
http://i98.photobucket.com/albums/l2...2091737-00.jpg

 

no point in posting a video if all you can here is **** music!

 

i forgot to turn it off, and you can still hear the motor

 

I couldn't see the video for some reason.

Have you checked your engine mounts? That'd cause a bucking.

 

yea the right side motor mount is bad and isnt the right one i dont think. but anyway changed the fuel filter and mounted it up on the bracket. think i found the problem. the gas that came out of the lines was almost black. and checked at the injectors and same thing. im gonna drop the tank this weekend and clean it and clean the screen, and the injectors, and run injector cleaner, then see how it runs.

 

wow, thats good news. You might consider a new gas tank if it's really bad and corroded.
good luck

 

yeahhh, the fuel pump on a 91 is in the tank isnt it? i might just replace the pump too while i have the tank out

 

yeah its in the tank, but there is access to the pump if you remove the rear panels/seats, so if you dont replace it now you can always do it later if you need to.

 

alright i emptied the tank and cleaned it, got a new pump strainer, new fuel filter, filled it with a fresh full tank of 93 gas, and put in a bottle of stp complete fuel system cleaner. but first i just filled up a gas can and dumped it in to get me to the gas station. on the way the check engine light came on (AGAIN) i filled it up and on the way home no check engine light. came home and dumped in the cleaner. drove it for about 10 minutes today and no check engine light or misfiring, and the car sounded a bit louder and deeper, but it still bucks a bit at partial throttle. could the car be like this for another reason? my dad says it seems like it has aftermarket cams or something. could that be the reason it does the bucking in only first gear and a second a bit?