barometric pressure is too low, what would cause it and what sensor, tru boost was installed but taken out ...ill try to get more info then that...04 mr is at my buddys shop and we cant figure it out

 

Barometric pressure, isn't that the pressure caused by the external atmosphere?

 

yeah thats what i was sayin to him but everything looks fine, we clear the codes and as soon as u start the car it comes up again, its not the maf or mass sensor either cause i swapped them with mine it the car was still doing the same thing (key on engine off)

 

I think he's trying to refer to a CEL but did so in poor fashion.

Sully, are you getting a code? What number is it?

 

p2228

 

Damn, I looked around and found that code mentioned a few times, but those people never resolved it, or at least they never posted about a resolution.

It seems it can be caused by an intake or by not tightening the gas cap all the way.

 

really???? i thought which i didnt do, is to swap the map sensor..and reset ecu and see if that would be it cause i thought thats where it reads it.... i appoligize about the poorly fashion mentioned cel but wouldnt think the gas cap would have anything to do with it...the kids got a injen uip and intake but looks and feels fastened pretty good

 

The gas cap is a long shot, so if that doesn't change anything, put the intake back to stock next.

 

will try...ill be back with results tomorrow

 

warr i dont think its that much of a longshot

A friend of mine drove his EVO from wisconsin to boulder, CO - he got the same code and his car was undriveable. The SIMPLY uncapped the gas cap (some pressure came out like it was a "carbonated soda" for reference), and then screwed it back on. Either the pressure in the tank built up while he went up with altitude (as all sealed food products do also) OR he didnt have the cap screwed on all the way for the 15 hour drive

 

wouldnt the evap take care of that

 

Are you living in altitude? what are the values you get with log? 78.5 correspond aprox to 2200m altitude....like Mexico city for example!

 

it was an o2 sensor

 

Sully,

A faulty or unplugged O2 Sensor?

 

I wish I got your friends gas mileage if he drove 15 hours on one tank(j/k)! I must have been a lose cap as I just went from sea level up to 7800' in NM and then down to 5300' in Denver with no issues. Granted when I stopped to fill up, pressure was let out of the tank but that is a normally pressurized system which is why when the cap isn't tight, it will throw a CEL as it can't build pressure.