"code 45: System Too Lean or Too Rich malfunction in the fuel monitoring systems"

wtf? I only have i/h/e and test pipe..... What to check?

 

my guess....

the O2 sensor in the test pipe is bugging out.....not reading correctly

 

Primary HO2S?
MAP sensor?
Exhaust leak?
Contaminated fuel?
Valve clearance?

 

I threw that code and I needed new rings.

 

its the test pipe. wrap your o2 sensor in tin foil should fix the problem

 

.....2nd o2 sensor is zip tied to the front swaybar and wrapped in tin foil.

Now bad rings, I could believe..... why would it throw that particular code though?

 

do you have an o2 simulator. this goes in place of the secondary. i would think that code only comes on for the primary o2 what mods. usually higher or low fuel pressure will set this code

or you have a bad o2 primary

 

All things being equal, it is usually a bad primary HO2S.

 

I get the same code and I am stumped! I replaced my secondary o2 sensor with a Bosch universal sensor. Maybe it's that one?

 

.....why are you guys saying primary o2 now?

 

The secondary HO2S is for checking catalyst function-it will give codes 63,65, and 67. The ECU uses the primary O2 for fuel trim-my experience has been code #45= bad primary HO2S.

 

Does any know of a cheap place to get o2 sensors or does anyone have a couple primary o2 sensors for sale for cheap for Black R and I?

Thanks!

 

..... that's definitely odd. I have an extra primary o2 sensor, so I'll install that and reset. If that code comes back, then I can rule it out.....

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tvrsir &raquo;</TD></TR><TR><TD CLASS="quote">usually higher or low fuel pressure will set this code
</TD></TR></TABLE>

 

.....stock fuel pressure regulator on my car. NO vafc.

 

Hrm...

Just plugging the fact that I did get a 45 after an AEM fpr install.

 

You need a fuel pressure regulator and get more fuel.

 

Black R - keep me updated on the code. Hopefully you don't get it so I can swap out o2 sensors also.

I have an fpr and I had the fuel too high so adjusted it to stock levels but still got a code 45. I'm guessing I fouled up the o2 sensor. I'm hoping that's all it is.

Thanks!
Gary

 

.....I haven't touched the car. I reset the ecu and it came back and I just left it.

Car is running pig rich and bumper gets covered in soot. *shrug*

 

could the sensor be shot from running so rich?

 

Sorry to bump such an old thread, but I'm getting the same code in conjunction with a rougher, lower idle and some hesitation/bogging. Did you ever fix the problem? I haven't done a new primary O2 yet..

 

i had that code before on my GSR, it was a malfunction of the o2 sensor. unplug it and check the resistance.. if someone has a helms, they can thell you the specifications.. mine was off spec, so i just bought a new o2 sensor and it was fixed, along with better performance and gas mileage than before.

i hope this helps.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dc2gsr94 &raquo;</TD></TR><TR><TD CLASS="quote">i had that code before on my GSR, it was a malfunction of the o2 sensor. unplug it and check the resistance.. if someone has a helms, they can thell you the specifications.. mine was off spec, so i just bought a new o2 sensor and it was fixed, along with better performance and gas mileage than before.

i hope this helps. </TD></TR></TABLE>


I swapped my primary and secondary o2 sensors as a test (since their functionally the same except for the rubber grommet thingy). I also used the o2 sensor fooler resistor trick for the now secondary sensor.

It worked! I got 250 miles out of the next tank of gas, then 280 out of the next tank after that, and a little over 300 out of this last one! Mixed driving, with higher mpg on the hwy. I must add that this is with the AC on full blast and toting around a project tranny, intercooler, miscellaneous tools + floor jack, and full set of wheels in the trunk area.

I am now getting a code 63 (it popped up after about 170 miles of my test) - which is secondary sensor...

I guess that sensor really was bad after all. Thanks H-T!!!

I wasn't worried about replacing that sensor since it doesn't affect anything but the CEL...


Modified by Black R at 3:58 PM 7/17/2004