Hi, how is everyone doing?

I just got my codes read today because the arrow on my dash was flashing and these were my results

p0730: gear ratio incorrect

p0331: knock sensor 2 circuit range malfunction

p0400: EGR flow malfunction


Any help on what these mean, how serious they are, or how to fix them would be great.

thanks

 

IMO the most serious of those could be the first one:
=================================================
DTC 322/P0730: GEAR RATIO INFORMATION INCORRECT
1) Check transmission oil level. If oil level is low, top off
as necessary and check for leaks. Repair as necessary. If oil level is
okay, turn ignition on and check DTCs. Test drive vehicle while
observing automatic transmission warning light. If light begins to
flash note any unusual symptoms in transmission operation or function.
If transmission does not show any mechanical fault or malfunction, go
to next step. If transmission has a mechanical malfunction and DTC 322
is not reset, repair or replace transmission as necessary.
2) Turn ignition off. Connect measuring unit to TCM. Raise
and support front of vehicle. Turn A/C off. Idle engine. Set gear
selector to position "D" so front wheels begin to rotate. Increase and
keep engine speed at 2000 RPM. Set DVOM to Hz scale, then connect DVOM
between measuring unit terminals No. 1 and 2. If DVOM gives a stable
Hz reading when engine speed is constant and transmission is not
shifting, go to step 5). If Hz frequency reading shows wide
fluctuations, go to next step.
3) Ensure ignition is off. Disconnect TCM. Connect ohmmeter
between measuring unit terminals No. 1 and 2. If ohmmeter does not
read 300-600 ohms, go to next step. If ohmmeter reads 300-600 ohms,
ensure RPM sensor wiring is not located near sources of interference
such as electric motors or spark plugs.
4) Disconnect transaxle connector. Check TCM connector for
poor terminal contact. Repair as necessary. Reconnect transaxle
connector. Connect ohmmeter between measuring unit terminals No. 1 and
2. If ohmmeter reads about 300-600 ohms, DTC was set because of poor
contact in transaxle connector. If ohmmeter does not read about 300-
600 ohms, replace RPM sensor.
5) Connect DVOM between measuring unit terminals No. 20 and
48. Shift transmission to "D" so front wheels begin to rotate.
Increase engine speed to 1800-2000 RPM. If DVOM displays a stable Hz
reading when engine speed is constant, go to step 8). If DVOM does not
display a stable Hz reading when engine speed is constant, go to next
step.
6) Replace VSS. Connect DVOM between measuring unit terminals
No. 20 and 48. Shift transmission to "D" so front wheels begin to
rotate. Increase engine speed to 1800-2000 RPM. If DVOM displays a
stable Hz reading when engine speed is constant, system is okay. If
DVOM does not display a stable Hz reading when engine speed is
constant, go to next step.
7) Ensure ignition is off. Ensure wiring between VSS and
instrument cluster is not located near sources of interference such as
electric motors or spark plugs. If wiring is okay, replace instrument
cluster. See appropriate INSTRUMENT PANELS article in ACCESSORIES &
EQUIPMENT.
8) Ensure ignition is off. Disconnect TCM. Connect ohmmeter
between measuring unit terminals No. 20 and 27 (solenoid S1), then
between measuring unit terminals No. 20 and 28 (solenoid S2). If
ohmmeter reads 10-15 ohms, go to next step. If ohmmeter does not read
10-15 ohms, check transaxle connector for poor terminal contact.
Repair as necessary.
9) Ensure ignition is off. Reconnect TCM. Turn ignition on.
Set gearshift selector to "D" position. Connect voltmeter between
measuring unit terminals No. 5 and 20. If voltmeter reads 0-.5 volt,
twist gear position sensor lever/shaft up, down, and to side. If
voltage reading remains constant, system is okay. If voltage reading
does not remain constant, go to next step.
10) Turn ignition off. Check gear position sensor adjustment.
Repair as necessary. See DTC 313: GEAR POSITION SENSOR SIGNAL
INCORRECT. If adjustment is okay, replace gear position sensor.
===============================================

The manuals I have are for '95 MY and usually reference the DTC 3 digit trouble code (i.e. OBD I) rather than the OBD II codes you referenced. I could help you more if you supplied the OBD I equivalents. Instructions on how to do that are here.

P0400 looks like low EGR valve flow; could be plugged valve or pipe.

Any symptoms of note?

 

I really like those read 850's.

Can you give a little history. Once I was low on has and sitting on a slanted road. The car was tilted and could not get to the gas that was in the tank (I was in front of a friends house talking to him). When the car shuttered and almost ran out of gas, I immediately told him I had to go and got the car on the level part of the street. When I looked down at the dash, the CEL came on. I went and got gas, then home to check the codes and I had about 4 or 5 codes in the reader. I reset the codes and the light went away, never to return. Wow! For some reason, running out of gas caused multiple codes to activate.

I said all that to say this... If you can, clear the codes and wait to see if they return. A few days ago, I was between gears, D & 3 and my transmission did not shift properly and wham, I got the flashing up arrow and a CEL. When I got home I checked the manual, cleared the code, and 350 miles later, no return.

If the car seems to be running good, I guess it would be a good idea to clear the code wait a day to two to see if it returns. Could be risky but it seems to work for me. The key may be to do it quickly (reset) and make sure the car appears to be running smoothly.