95 Sonoma Electrical / Starting Issue

I have a 1995 Sonoma, 2.2l 4cyl, Manual trans, 2WD that I am having trouble starting. Initially I had a problem when driving that I would lose all power and the engine would die. I would nurse it to the side of the road and let it sit for a few seconds and it would start back up, as long as my dash lights came on (if they didn't, it would not start). I found that the battery cable to the starter was loose and tightened it. I had no problems for about a month or so.

Last night, it did the same thing. It started back up and ran fine, but when I got it to my house it will no longer start. Today I checked the starter wires and they were tight. I removed the starter and had it and the battery tested, both were fine. I replaced the starter cable to the battery. I conducted continuity tests on all wires leading from the starter, alternator and into the dash and all seems fine.

The current symptoms: it will turn over fine, but will not start. The dash lights come on very dim (barely able to see) except for the seatbelt warning light, which comes on bright. All accessories work fine. It has OBD-II, but I cannot find a scanner that will read it (I guess the dealer will have to do it at some point). Any ideas?

The dim lights sounds to me like possibly a bad battery connection. Make sure that the terminals on the battery are clean from corrosion, also if its an older battery be sure the terminals are tight inside the battery. On a battery I had the terminal loosened up and completely fell out of the battery, so I got a new one since it was old anyway.

If the terminals are good then you'll have to do some checking with a multimeter and find the bad circuit. With circuits a bad ground or a faulty component anywhere can cause problems somewhere else. Better have it scanned at a dealer or somewhere to get the trouble code, then we'll have a better idea of whats wrong.

Check connections very closely, take the battery cables off of the battery and look at the connecting surfaces. Must be clean and shiny. Check the ground cable as well, both ends. Also check the body ground cable, it runs from the cylinder head to the body of the vehicle.

1995 was a change over year for OBD systems on GM S&T series vehicles. Your vehicle could have any one of 3 systems. The OBD system will not cause problems like you're experiencing, scanning for codes will not help in locating the problem.