Questions and Answers

Chevy Astro Multiple DTC's
Q. My question is concerning a 1998 Chevy Astro 2WD. I am a moderate DIY but my specialty has never been transmissions. I am getting multiple codes and I have been able to find references or literature about all except P0785 - shift solenoid malfunction 3-2 shift solenoid circuit electrical.

I also am getting P1860, and P0740. Any help on location of the shift solenoid and relation to the torque converter clutch solenoid would be greatly appreciated.

In reference to an email I just recently sent you concerning a DTC P0785, I am just finding out that there is an arc in the distributor cap or rotor and a code for a random misfire P0300.

I read many of your articles, and as I said I am not a transmission specialist by any means, but I noticed that you said it is possible to get incorrect dtc's for the trans if engine problems are present.

I am going to get a look at the distributor cap or rotor as soon as possible. Is it possible that once the misfire is corrected that the DTC's for the transmission will disappear? Any help is greatly appreciated.

A. While possible, I doubt that will solve all your problems. All shift solenoids are accessed by removing the pan. You should really try to get a service manual for these codes as the solenoid may not be the problem. It could be wires to them or junk floating around inside the valve body.