vss issue.. no mph with scan tool
#1
Teching In
Thread Starter
Join Date: Mar 2009
Location: Utah
Posts: 44
Likes: 0
Received 0 Likes
on
0 Posts
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
I just swapped a 6.0/4L60E in a 72 chevelle and I'm having a problem.. I can't get the car to shift and I heard if the ECU does not read MPH properly it will cause this to happen. Well, My OBD II autoscanner has a live feed mode which reads out MPH and sure enough it stays at 0 mph while in gear and driving..
I checked the ecu right at Pin 21 on the red connector ( PPL/WHT ) VSS Input and it has continuity from the VSS plug itself, so why in the world would the ECU not read any MPH? I can understand my gauges not showing mph since I haven't calibrated my gauges yet with the VSS output wire but I don't understand why the ECU doesn't read the MPH since the VSS input wires are connected properly in the harness with the proper gear ratio and tire size flashed in.
Any suggestions? I need to get the MPH working next and then see if it fixes the no shift issue, But regardless, if it doesn't fix the shift issue I still need to get the MPH readout working so the ECU knows when the car is moving.
Thanks!
I checked the ecu right at Pin 21 on the red connector ( PPL/WHT ) VSS Input and it has continuity from the VSS plug itself, so why in the world would the ECU not read any MPH? I can understand my gauges not showing mph since I haven't calibrated my gauges yet with the VSS output wire but I don't understand why the ECU doesn't read the MPH since the VSS input wires are connected properly in the harness with the proper gear ratio and tire size flashed in.
Any suggestions? I need to get the MPH working next and then see if it fixes the no shift issue, But regardless, if it doesn't fix the shift issue I still need to get the MPH readout working so the ECU knows when the car is moving.
Thanks!
#6
TECH Veteran
iTrader: (4)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
A 6.0 would have originally came with a 4l80e, what harness are you using? Did you mod it for the 4l60e? Did you have the 4l60e trans segment swapped in the tune? Also you say you checked continuity on one vss wire, did you check the other one too?
Last edited by ls1nova71; 07-12-2012 at 07:52 AM.
#7
LS1Tech Sponsor
iTrader: (5)
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
What year is this engine/trans combination?
Jon
PSI
Jon
PSI
__________________
![](https://ls1tech.com/forums/signaturepics/sigpic84531_2.gif)
Your Source for LSX Conversion Parts!
www.psiconversion.com
Ebay Store
Facebook/psiconversion
Instagram/psiconversion
'Dont Let EFI Pass You By!'
![](https://ls1tech.com/forums/signaturepics/sigpic84531_2.gif)
Your Source for LSX Conversion Parts!
www.psiconversion.com
Ebay Store
Facebook/psiconversion
Instagram/psiconversion
'Dont Let EFI Pass You By!'
Trending Topics
#10
TECH Senior Member
![Default](https://ls1tech.com/forums/images/icons/icon1.gif)
Good luck. This thread is ten years old.