so I still cant figure out why my car hesitates at 3.8-4k rpm in tip tronic when I step on it. I plugged in a friends match obd scanner and no codes came up. But when my buddy checked the systems perimeters like fuel and such. Fuel said complete but cat converters said incomplete as well as I think emissions. Other than that everything was complete. Anyone know what could be wrong or is this normal for these scanners

 

Have you reset the codes recently? Or unplugged the battery?

Usually the system monitors get reset when the codes are erased. It takes a period of time for them to reset and if they don't, you get a CEL light eventually once the fault is found.

Does the scanner you use have the ability to check pending codes? These are intermittent codes that the computer has not collected enough info on to display the CEL just yet.

Without knowing exactly what the monitors were that were INC, it's hard to speculate.

 

I'm willing to bet one or more of your O2 sensor's are gone.

My dads truck did the same thing, and I told him to check his O2 sensor, but he brought it to a mechanic instead who said it just needed a tune up. $400 later and his truck still hesitated around 3k rpm. I borrowed his truck for the weekend, swapped out the O2 sensors and the truck ran like it was brand new. Returned the truck with the bill for the O2 sensors and told him the gas I used was for the hour in labour I spent swapping them out.

 

I would also venture it's an O2 sensor issue. However, there would be a code for that.

That's why i'm asking about the "pending codes"

 

My dads truck threw no codes either which is why the mechanic told him "it just needs a tune up".