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New User
Posts: 6
Joined: 02/12
Posted: 02/29/12 06:43 PM

every thing is going to be ok now  

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Posts: 194
Joined: 02/10
Posted: 02/29/12 07:59 PM

i would have answered you earlier. but my desk top computer was apart for service..

since you have An OBD2 car..  that monitors all kinds of stuff..

what codes is it setting..  

instead of just reprogramming the computer..   Reflashing the computer is what it is called...

they should be taking the car for a test drive with TWO mechanics...   one to operate the scan tool..  the other to operate the car...    the scan tool should be set to the record data stream mode... so its constantly monitoring the data stream...  when the car fails.. the passenger pushes the button to take a snap shot of the data stream..

a drivability tech who really knows his stuff .. should be able to page back and forth through the recorded frames of data stream to see what failed..

i personally would like you to run a test... your self..   do you have a hand held digital volt meter...

set it to 20 volts DC scale...      start the engine and turn on the headlights..

1.   measure from the POSitive battery post.. to the NEGative battery post...  14.1 to 14.8 volts is expected..

2.   measure from the NEGative battery post to the engine ...          0.04 volts is expected..

3.   measure from the NEGative battery post to the body...      0.02 volts is expected.

4.  measure from the ENGINE block to the BODY..       0.02 volts is expected...

if you get 0.00 on tests 2, 3, 4   set the meter to 2 volts DC scale..   recheck 2, 3, 4....

this takes less than 2 minutes to ***

i have had terrible problems with the ground wires on the core support..  they are on either end of the radiator core support.. there is usually one near on the inner fender panel..

when a LOT of modifications get done.. sometimes ground wires get left off..  or end up being too short..  sometimes they get installed on painted surfaces..

one had to realize.. that ON ALL CARS...   the ground wire is HALF the circuit..

each separate ground wire is for a different circuit.. they are NOT interconnected...  except where they are attached at the body...

what really sends a curve ball.. is the electrons actually flow from Negative to positive...

if you loose a ground connection.. you won't have enough electrons to operate the circuit...  kinda like the your computer power wire falling out of the wall socket..  no power..  no POWER...

run the test above...   post results..

digital volt meters are cheep.. decent ones under 22 bucks..

does every mechanic know that test.. NOPE..   its usually taught the first week of autoshop.. when nobody understands anything yet..  

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