teabagger

Actually it's not an Audi but you guys seem to know your stuff on this site, what usually causes high NO readings on an emission test? it was 1238 with a max of 847. I am thinkin cat but I duno.

thereedster

either cat, advanced ignition timing, or inoperative egr if the car is so equipped. nox is caused by high exhaust gas temps.

teabagger

That makes sense b/c I know she got her tbelt done a year ago and on the test it failed ignition timing, now I just gota go take a look to see if the belt is off a tooth or if the dist. is moved. When using a timing light tdc on the crank pully is when it is firing the #1 cyl.? it's been a while...Thanks.

tonyj

if so equiped to put the ECU in ignition default mode - no timing overrides.