understanding diagnostics

[LEEWSEE]

i posess a handheld scanner that does quite alot on 2005 vw/audi and older. with that in mind, can such a tool tell me if a seller has erased DTCs? there must be a way for the scanner to reveal whether readiness codes are set.
thank you

[old guy]

i posess a handheld scanner that does quite alot on 2005 vw/audi and older. with that in mind, can such a tool tell me if a seller has erased DTCs? there must be a way for the scanner to reveal whether readiness codes are set.
thank you

Once DTC's are erased they are gone. However, your scanner should be able to give you the status of the readiness monitors. That's pretty basic stuff for any scanner.

[Seerlah]

Another thing you may want to confirm is if the CEL even illuminates. Just put key in accessory position. But if purchased from a dealership, they should have handled that before new ownership...and possibly a few other adjustments . So, you may want to investigate odometer roll back if possible. Changing the readings can be done with a cheap ebay Vag Tacho cable. Highly illegal, yet easily done (so I heard).

[LEEWSEE]

Once DTC's are erased they are gone. However, your scanner should be able to give you the status of the readiness monitors. That's pretty basic stuff for any scanner.

READINESS CODE STATUS PRETTY MUCH LOOKS LIKE BINARY CODE...HOW DO I INTERPRET IT?
ALSO, IS CARFAX A GOOD SOURCE TO CHECK FOR ROLL-BACKS? ANYONE KNOW OF A LESS EXPENSIVE WAY TO CHECK?
FINALLY, I HAVE HEARD THAT REMOVING THE OIL FILL CAP TO CHECK FOR PRESSURE (BLO-BY) IS A GOOD CHECK FOR GENERAL ENGINE HEALTH. MY b5 HAS NEUTRAL PRESSURE WHILE MY WIFES 2017 a4 HAS ALOT OF VACUUM. I REALIZE THAT THESE TWO ENGINES ARE VASTLY DIFFERENT, BUT AM I ON THE RIGHT TRAIL HERE??
I HAVE INSPECTED 3 CARS NOW AND WITHOUT EXCEPTION THEY WERE ALL NEGLECTED - OIL LEAKS, DEFERRED MAINTENANCE, YOU NAME IT.

[MurkyRivers_A4]

Why are you yelling....

[chad99]

The following is all free!
Get the myCARFAX app, add car to your list via plate number, this will give you history of the car if reported by repair centers and if local DMV keeps records of smog check along with the mileage the smog check was done at, plus you get the vin number that matches the license plate to confirm it matches the car.

Once you have the vin number there are a few websites that will tell you if it was salvaged, sold at auto auction as salvaged, taxi use ect, again all free!

[chad99]

Readiness you want all 0s if I remember correctly

[Seerlah]

READINESS CODE STATUS PRETTY MUCH LOOKS LIKE BINARY CODE...HOW DO I INTERPRET IT?
ALSO, IS CARFAX A GOOD SOURCE TO CHECK FOR ROLL-BACKS? ANYONE KNOW OF A LESS EXPENSIVE WAY TO CHECK?
FINALLY, I HAVE HEARD THAT REMOVING THE OIL FILL CAP TO CHECK FOR PRESSURE (BLO-BY) IS A GOOD CHECK FOR GENERAL ENGINE HEALTH. MY b5 HAS NEUTRAL PRESSURE WHILE MY WIFES 2017 a4 HAS ALOT OF VACUUM. I REALIZE THAT THESE TWO ENGINES ARE VASTLY DIFFERENT, BUT AM I ON THE RIGHT TRAIL HERE??
I HAVE INSPECTED 3 CARS NOW AND WITHOUT EXCEPTION THEY WERE ALL NEGLECTED - OIL LEAKS, DEFERRED MAINTENANCE, YOU NAME IT.

Why are you yelling....

I think he missed a spot

[chad99]

Those are the only two that are suppose to be in caps lol

[Seerlah]

hahaha

Truth be told, I didn't even read the post first time around. Just seen B5 A4

[LEEWSEE]

my car displays: 00110011...many drive cycles.

[LEEWSEE]

The following is all free!
Get the myCARFAX app, add car to your list via plate number, this will give you history of the car if reported by repair centers and if local DMV keeps records of smog check along with the mileage the smog check was done at, plus you get the vin number that matches the license plate to confirm it matches the car.

Once you have the vin number there are a few websites that will tell you if it was salvaged, sold at auto auction as salvaged, taxi use ect, again all free!

thanks

[old guy]

my car displays: 00110011...many drive cycles.

More than you ever wanted to know about readiness: Clicky click®

0=passed. 1=failed