Btothe3rdDegree

so i am getting bad gas mileage and it hesitates on acceleration til about 3000 rpm in 2 and 3 gear. so i am guessing it is my o2 sensor, oh also it throws a 43 which is a o2 sensor (on a 92 civic) so is there a good way to test it besides checking the voltage or should i just replace it because of the symptoms? any help would be great!!

CXHatchback

If you're throwing a code you should definitely replace it.

Btothe3rdDegree

the thing is the code is "Fuel supply system oxygen sensor" so i want to make sure it is the o2 sensor

h22civic95coupe

What are the symptoms btothe3rddegree?
what kind of hesitation you are talking about, does it happen every time, or just once in a while?

Hybrid96EK

What engine are you running? According to the helm, 43 is Fuel Supply System ONLY. Code 1 is the O2 sensor. Have you modified your fuel pressure regulator? Installed an aftermarket pump? Have any idea what your fuel pressue currently is?

h22civic95coupe

code 43 is o2 sensor on h22

Hybrid96EK

I guess that would depend on the ECU and what engine you are using. I just looked up the code for a 92-95 Civic.

Btothe3rdDegree

ok its a 92 civic lx and according to Haynes a 43 is a "Fuel supply system oxygen sensor" the symptoms are that my gas mileage is really bad now, and mostly in second gear it is laggy til around 3000 rpm, kinda like when vtec kicks in. the engine is a d15 b7 and no i have not messed with the fuel system except i have adjusted my accelerator cable. in haynes is says to check the fuel pressure, fuel pressure regulator, and look for vacuum leaks. anther thing i noticed is after a while of driving i dont havew a constant idle it jumps up and down about one tick mark no much but could be sign of a vacuum leak.

Hybrid96EK

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Btothe3rdDegree &raquo;</TD></TR><TR><TD CLASS="quote">ok its a 92 civic lx and according to Haynes a 43 is a "Fuel supply system oxygen sensor" the symptoms are that my gas mileage is really bad now, and mostly in second gear it is laggy til around 3000 rpm, kinda like when vtec kicks in. the engine is a d15 b7 and no i have not messed with the fuel system except i have adjusted my accelerator cable. in haynes is says to check the fuel pressure, fuel pressure regulator, and look for vacuum leaks. anther thing i noticed is after a while of driving i dont havew a constant idle it jumps up and down about one tick mark no much but could be sign of a vacuum leak.</TD></TR></TABLE>

I am pretty sure thats the problem. Get some carb cleaner or something and spray it around the hoses to see if you can find the leak. When you find it, the idle should drop some depending on what chemical you use.

Btothe3rdDegree

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hybrid93Eg &raquo;</TD></TR><TR><TD CLASS="quote">

I am pretty sure thats the problem. Get some carb cleaner or something and spray it around the hoses to see if you can find the leak. When you find it, the idle should drop some depending on what chemical you use.</TD></TR></TABLE>

even with cel it is throwing?

Hybrid96EK

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Btothe3rdDegree &raquo;</TD></TR><TR><TD CLASS="quote">

even with cel it is throwing?</TD></TR></TABLE>

Yes. Keep in mind a vac leak will cause a series of problems including low pressure at the rail.