Quick question:

If my truck throws a DTC code, then I go and have it erased at AUtozone, if the problem still persists, will it throw the code again?

Reason Being about every other month I get the same code 1135 1152, I clear them and forget about them then a month or two later it re-appears. Is that only becuase it took a month or 2 for the problem to resurface?

 

Partial answer.......I am sure Chris will clarify.

I know when you throw a soft code the CEL will not come on right away. The same occurance must happen (I beleive) 2 more times before the CEL will illuminate.

--Joe

 

sometimes the pcm needs to see the concern several times before it will store a code and illuminate the check engine light.

it's not a hard fault, like an open or shorted circuit or the light would come on much earlier.

it's also possible that you have an intermittent concern, or that the concern is borderline, and it only exceedes the acceptable perameters or range that the pcm condsiders to be normal once in a while.

it depends on how much you drive your truck.

it could be lots of reasons.

I would recommend using an NGS or similar scan tool to actually monitor the hegos and fuel trims while driving and see what the pcm is really seeing.

a wideband meter would also be a nice thing to have in a case like this to see if the truck is really running rich, or there is a problem with the sensors.

good luck.

later,
chris