99 s10 ecm issue

[metallica21156]

i have a 99 s10, 4.3 manual trans with 4x4. the issue i have is the abs and ses light is on. connected snapon mt2500 scanner, i can read abs fine. as soon as i ask it to read data or codes from ecm it blanks out and restarts. i even completely unplugged the ecm, same thing. any ideas? any wires to check for shorts or grounded? basically the engine idles ok and light throttles ok but under heavy load or acceleration it missis but no blinking ses. so i need to read the codes. i tried using the scanner on another truck and it read ecm fine.

[MT-2500]

Originally Posted by metallica21156

i have a 99 s10, 4.3 manual trans with 4x4. the issue i have is the abs and ses light is on. connected snapon mt2500 scanner, i can read abs fine. as soon as i ask it to read data or codes from ecm it blanks out and restarts. i even completely unplugged the ecm, same thing. any ideas? any wires to check for shorts or grounded? basically the engine idles ok and light throttles ok but under heavy load or acceleration it missis but no blinking ses. so i need to read the codes. i tried using the scanner on another truck and it read ecm fine.

Are you using obd 11 or engine vin setup on scanner?

Can you run by AZ and see if there scanner will read the engine codes?

[metallica21156]

it will let me enter vin fine. then i get to the main screen to select to read codes or data. when i select anything it restarts.

[MT-2500]

Originally Posted by metallica21156

it will let me enter vin fine. then i get to the main screen to select to read codes or data. when i select anything it restarts.

Try for OBD11 codes.
Let us know how that goes .

[metallica21156]

it read the codes on obd2 mode so i dont know why it wont otherwise. it came up with o2 sensor bnk 1 sensor 1 no activity. found it unpluged. truck still runs bad no ses yet. the only thing ive noticed is that bank 1 sensor 3 doesnt seem to be working. do you know where that might be?

[MT-2500]

Originally Posted by metallica21156

it read the codes on obd2 mode so i dont know why it wont otherwise. it came up with o2 sensor bnk 1 sensor 1 no activity. found it unpluged. truck still runs bad no ses yet. the only thing ive noticed is that bank 1 sensor 3 doesnt seem to be working. do you know where that might be?

Did you clear codes and drive it?
Does bank 1 and bank 2 sensors work now and read the same/even?

Did you drive several miles and get it to go to closed loop?

If senor 3 not working check wiring plugin and switch or replce that sensor and check for working.

I would also go by your auto parts place and get them to check it with there computer tester.

[metallica21156]

well i told scanner that truck was a 98 and it works fine now. i did how ever find that both o2 sensors were stuck reading lean. changed them out and alot better. now need new u joints. driven several times and no ses so it should be good. still seems to be lacking power past 3000 rpm. by the way its a 5 speed.