IS q31 (IAT? EVAP?) important? Im geting ready to hit the dyno in a week an half, an was looking at my used p28 i bought an that q31 is toast! I un-sodered it an looks like maybe the bord might be bad to. (due to Q31 heating up)

I will be getting tuned with uber or Crome.

Will i through CEL?

iv searched an searched! an some people lean twords leave it off, not needed.

my car is a 2000 civic si, with the p2t ecu, being converted to obd1 with p28!

Any info helps! im new to chipping an dont want to waste my time on a bad ecu. unless there is a chance...

 

It controls the evap solenoid.

Most cars don't run them after modified. So most ecus you can get away without it and it will still be just fine.

 

if Q31 fried in your car, make sure you double check the IAT sensor to make sure it didnt melt out. most people plug the purge plug into the IAT sensor which burns the sensor and also Q31. replace the IAT if burnt and plug in the right plug. it should be a green wire and a red wire i think

 

yep, same happened to me about 6 years ago, im still running the ecu today, i had the IAT and IACV plugs backwards, and yes it did melt the IAT probe tip.

not much to worry about, just getting that burned electronic smell outta your car

 

would your car pass califonia smog with q31 fryed?

 

nope you won't pass emissions. q31 is for evap purge solenoid. It will run fine without it. Just don't try to use evap output to control anything because it won't do anything.

 

Thank you abk. thats very good to know

 

i noticed the same thing when i chipped my used p28 this weekend.

and as everyone here said. use it and don't worry about it.

so cheers.

 

So does anyone know where to get a replacement transistor besides a spare ecu cuz my po6 and p28 have the same transistor fried

 

here you go
http://www.xenocron.com/xenocron-q31...tor-p-335.html