no scantool signal

[klcsmooth]

Im not getting signal from scanmaster was working fine until I changed wiring harness and computer. Was driving fine lost signal car started running rough then it cleared up but no scantool signal. put in a new computer got signal from scantool drove fine for a couple of minutes same senerio lost signal ran rough cleared up no scantool signal. Now I have two computers that dont send signal to scantool. I dont wont to buy {waste my money}another computer until I solve this problem. Could there be a wire grounded that should not be? Any ideas will be helpful.

 

[Dan Thompson]

I would disconnect the scantool until the car is running correctly.

Which scan tool is it?

 

[topfuel]

Clean and tighten the grounds on the rear of the passenger side cylinder head.
Same thing happened to me recently and it went away after
reconditioning the grounds.