I have a 1995 chevy tahoe 5.7 350 TBI, that keeps giving me the code 42 on it I have replaced the coil.spark control module, distributor cap rotary button plugs wires and it still give me this code and will surge foward when I stop after about 50 miles of driving I have replaced the injectors throttle body and any plug that is under the hood can anyone help me please, Thanks Larry

 

is this obd1?

 

Yes It is the OBD1 connection on it ,I have tried to remove the battery cable to clear it but it comes back on, after about 20 miles or so once I shut the motor off it will even go off its self sometimes but it will develop a skip when it comes on ,it runs good untill the light is on I have looked at the wires under the hood for bad ones and even sprayed the connector cleaner in them Thank you for the quick reply back

 

What I read on that code is something to do with ignition bypass circuit. I don't know on a 95, but, earlier models with hei had a bypass circuit of the starter solenoid. When the starter was engaged, the post (facing starter solenoid) on the left contacted, and put full battery voltage to the distributor. After the starter was disengaged, there was a resistor circuit that then supplied a reduced battery voltage to the distributor. I'd look at that, again, I am not sure on a 95 model.

 

Thank you so much for your reply I will take a look at this and check all the wires and connections you have gave me a lil hope in this case and I will let ya know how it goes once again Thank You so much for your time and kindness Larry.