Hesitation at 6300 elev.

[usasail]

Hi I just moved from Texas to Wyoming and now at 6300' in elevation. I have an 03' Baja with 116k mileage, also with all original oxygen sensors. I've started to get hesitation while engine was cold now it's starting to hesitate while warm as well.

Would it just be a replacement of sensors or is there a setting somewhere to allow more oxygen in that I can adjust?

Thanks for the help.

Monty

[Legacy777]

Hi Monty,

 

Welcome to the board. If your O2 sensor is old, you may want to go ahead and replace it.

 

The ECU will automatically adjust for changes in elevation. Another you can possibly do is reset the ECU so it's learning memory is starting off from higher elevations, rather than lower elevations. That should help speed up the learning of the ECU.

[bheinen74]

at least you dont have this one, which i had to search for, i thought maybe you bought the one in this thread http://www.ultimatesubaru.org/forum/showthread.php?t=93179&highlight=baja+dies+mountains

 

 

but that was a 06 model baja.

good luck though.

[edrach]

Hi Monty,

 

Welcome to the board. If your O2 sensor is old, you may want to go ahead and replace it.

 

The ECU will automatically adjust for changes in elevation. Another you can possibly do is reset the ECU so it's learning memory is starting off from higher elevations, rather than lower elevations. That should help speed up the learning of the ECU.

How do you reset the ECU?

[usasail]

Cool Thanks Legacy777. Yep that other Subie owner from Colorado had some multi issue's I guess. Since I've posted the check engine just came on, it's been about a week and 1/2 since issue started. My brothers think it's not the O2 sensor since it happens right away once load is established in reverse. I'll try the ECU reset, but if I could repeat Ed's question of how you might go about doing this?

Thanks again,

Monty

[OB99W]

[...] Since I've posted the check engine just came on, it's been about a week and 1/2 since issue started.[...]

It's probably best not to clear the ECU memory until you have any stored trouble codes read, since they could help determine what the problem is. Typically major auto parts stores like AutoZone, Advance, etc., will do that at no charge. If you have it done, try to get the code(s) (Pxxxx), not the code definition(s), and let us know about any.

[usasail]

Hi guys - Thanks again for the info. Yeh I asked my bro's and they said to clear the ECU just take off the negative terminal of the battery. I did that it cleared the "Check Engine" so no more codes available...but I think that did the trick. I'll keep my eye on it if it acts up again and if the check engine light comes up again I'll be sure to get the codes.

My brother was right this is the best Subie shop in town:banana:

[unibrook]

My brother was right this is the best Subie shop in town:banana:

 

Yah dat's right you bet it is Hoss!

 

Reply back here even if the symptoms don't reappear. That will help others in the future if they experience the same problem.

[unibrook]

To wrap this thread up. He needed a new spark plug. Code was for a cyl 4 misfire, iirc. Anyway, new spark plugs all the way around did the trick. Thanks all for helping.