Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: madmorty on 05 December 2007, 17:03:03

Title: help with codes
Post by: madmorty on 05 December 2007, 17:03:03

 :-/ Done Paperclip Test On My Omega 2lt And I Am Getting The Codes
38 -oxygen Sensor Circuit-voltage High And 73-mass Air Flow Temperature-voltage Low, Can Anybody Help Me With This Problem And Where Is The Oxygen Sensor Circuit

Title: Re: help with codes
Post by: magnul on 05 December 2007, 17:14:46

I have a feeling that these may be related, and that only one of them is real, but I'll leave the diagnostics to the grown ups.
The oxygen sensor is positioned in the downpipe before the cat. A connector is on the side of the transmission. This circuit is fed with a 5V reference signal from the ECU as well as heating wires. The sensor itself can easily be tested in situ* with a DMM, but can be misleading if the MAF is playing up as well.

*The black wire is the signal wire. When measures vs ground it should fluctuate between ~0.1 and ~4.7V approx one time pr. second.

One of the seniors will probably answer you shortly

Title: Re: help with codes
Post by: Marks DTM Calib on 05 December 2007, 17:17:58

I would start by checking for air leaks etc on the inlet system......

Title: Re: help with codes
Post by: madmorty on 05 December 2007, 19:21:21

would this problem cause my car to run uneven and spluter and stall :'(

Title: Re: help with codes
Post by: TheBoy on 05 December 2007, 19:22:46

Quote

would this problem cause my car to run uneven and spluter and stall :'(

Yup

Title: Re: help with codes
Post by: madmorty on 05 December 2007, 19:28:15

are there any photos ofthe pipes i need to look at

Title: Re: help with codes
Post by: Marks DTM Calib on 05 December 2007, 20:12:52

Also check the EGR is not sticking.

The inlet pipes are the big trunking from the air filter to the throttle housing.

Title: Re: help with codes
Post by: arthill on 07 December 2007, 20:40:17

Is it true that where several codes show up the first one on list is the most urgent as some of the others may be as result of first fault, ie. that should be tackled first then re-read?.