Noil

I thought I was having an issue with the catalytic converter (thread here: https://www.yotatech.com/forums/f2/i...verter-301913/) however that was just the symptom of the problem and not the problem itself. I had to replace the original 97 motor with a 2001 motor in the last 6 - 8 months; everything was working ok as far as no codes up to 3 months ago when I started getting P0172 Bank 1 burning too rich. After doing a lot of reading on P0172 and replacing the front O2 sensor I am still getting the code and believe the Mass Air Flow Sensor is causing.

Wasn't able to get the air box and MAF sensor with the new motor so the 97 air box and MAF is connected to the 2001 motor. I am wondering if there is a calibration issue because of the difference in the 99 - 02 MAF sensors.

I have some data from today's trip when it coded, and it looks to me like the MAF is causing an error and thus its throwing the fuel ratio to insanely rich. The code event is near the end of the data file at around line 497. If someone who is more familiar with the numbers of what the fuel trim and MAF is supposed to be could look at this and let me know if I am correct in my theory the MAF is the culprit it would be very much appreciated.

Thanks to all for your help!

vital22re

iTrader: (2)

Are you using the injectors from your motor? 99+ injectors are different from 96-98. High impendance vs. low.

75w90mantraN

Good troubleshooting.
Are you able to switch out your 97 airbox and sensor with a salvage one from a '01? I know you mentioned where you live is isolated, but maybe having it shipped would save you more headache.

Thinking about it, there were some changes between those model yrs. Even the body style can be an issue as some folks have mentioned with switching front bumpers.

I know with readings on MAF, it's suppose to rise as fast as you push on the accelerator and fall as you let off. With rich fuel reading, maybe there's a way to adjust for more air through your current intake. If you're using a k&n air filter, my thought is to switch back to an original. Maybe the airbox has a structural restriction that you can modify.

Not able to see the attachment. Maybe pics of the images?

Noil

Using the 2001 injectors in the 2001 motor so shouldn't be any electrical gremlins there. Have purchased a 2001 air box and MAF last night on ebay ... I tried for 2 months to get one in Canada from a salvage yard without any luck; so I just paid to have one imported from Florida. Will likely be several weeks before I get it. I have the pin-out saved on the computer and will get the harness pinned out to the new MAF and see how that goes. Is there any special tool I need to get to have the pins to release in the MAF plug?

My brother did ask me an interesting question regarding this issue; he wondered if the ECU needs to be flashed by the dealership because of the differences in the 96-98 and 99-02 motors. Anyone got any ideas on that possibility?

Thanks for the help!

Noil

Well it has taken a few weeks but I finally got the issue fixed. For anyone interested in what I had to do to get the issue resolved:

1) replaced the front O2 sensor
2) tried cleaning original 97 MAF - failed to resolve issue
3) replaced MAF and airbox with a used 99 - 02 sensor style and switched wires as needed - Got too lean code afterwards
4) replaced the rear O2 sensor - failed to resolve too lean issue
5) cleaned 99 - 02 MAF thoroughly
6) disconnected battery for 40 minutes to reset the computer - all codes cleared and issue is fixed

So now I have driven over a thousand km's since switching the MAF and replacing the rear O2 sensor no issues, way better fuel mileage and more power.