Need help with 4l60e lock up

[jgsg7476]

I need help troubleshooting my 4l60e. Sometimes the converter lock ups and sometimes it doesn't. It has a street bandit 9.75" 4l60e, 2800-3200 stall converter w/ls1 lock up. I can drive 100 miles and locks up fine but when I stop and then start again it will not lock up.

[SommersRacing]

Make sure the converter clutch signal valve is blocked in the valve body. This valve stock with cause a intermittent no lock up. Also make sure the TCC valve in the pump is not sticking. Matt

[jgsg7476]

Thanks.... I will check it out. I been checking the electrical side. It keeps saying trottle position sensor. I have changed it out and it still shows the code. The computer is commanding the fourth gear but doesn't seem to be going into gear. Thanks for the advise and I will check what you are saying next.