O2 sensor questions

Berda · 05-09-2006

Car is '91 talon AWD. I am trying to figure out why it is getting poor gas mileage. around 200 miles per tank.

I tryed testing my o2 sens using this site http://www.geocities.com/motorcity/d.../dsmtests.html

Everything other than the o2 sens checked out so not sure what to do next.

It says if you use an ohmeter between pins 3 and 4 you should get 12 Ohms of resistance when engine is cold (60F) and 30+ ohms when hot (Operating Temp) I tested 2 different o2 sensors and couldnt get either of them to show resistance between those two pins.

I also used the o2 sensor test port (under pass side kickpanel) to test voltage for my A/F readings .1 =lean; .9 =rich. and i couldnt get any steady reading at all (probably because it was a digital multimeter) It wouldnt read above .5 V. I think it may be either a faulty wire beween the ECU and sensor, or the sensor itself (which was replaced in '03). (i know i talked to you Steve about this)

Also it mentions an exhaust grounding strap. Does anyone know where that is located?

I know these o2s are shitty, and arent reliable. Anyone have suggestions for me? How much is a wideband o2 approx, and what are its advantages/disadvantages to my car, which is stock ATM (goal is making 300 or so HP).

Would an A/F guage be of any help to me or not?

Thanks for any help,

Adam L.

clean2g · 05-09-2006

Quote:

Originally Posted by Berda

Also it mentions an exhaust grounding strap. Does anyone know where that is located?

If this is what I think you're taking about, on my 2g it's like mid way down on the exhaust going back towards the end of the car. Looks kinda like a shoe string but its like metal mesh wire or something mounted on the chasis. If it's not there it may have also just borken/rusted off.

Quote:

Would an A/F guage be of any help to me or not?

I don't think an A/F guage would do much since they're not very accurate.

Other than that I'm not sure what to tell you. I know you've been trying to figure this problem out for a while so I'm sure you've gone through the basics. Have you tried taking it in anywhere to get checked? Good luck.

Andrew7dg · 05-09-2006

Is there any other symptoms the car is having like rough idle? Have you been smelling rich unburn fuel? anything like that
I would first narrow the problem down before upgrading anything.
like clean2g said, an Air fuel meter isn't always accurate.
with 300hp as goal I don't think you would need the wideband 02 just yet, if you are on a budget you can spend the money somewhere else. However wideband with logging capibilities is pretty nice to have for tuning.

Don't take it just anywhere unless they work on DSMs. the last place I took mine to when I had a problem with it was a local garage, told me it was the spark plugs and probably needs a new 02 however they told me they don't usually work on the turbo DSMs, Then charged me $60.00. Later I found out it was a boost leak.

Berda · 05-10-2006

i went to lse and they said the o2 sens wasnt reading 100%. I dynoed the car a few weeks ago and got 161 @ 12psi, and they said it was running really rich.

Berda · 05-13-2006