Truck not starting properly occasionally it starts by hotwire or occasionally with key

2002 CHEVROLET S-10

212,519 MILES • 2.3L • 4 CYL • 2WD • MANUAL

PHIL SPIRES

MEMBER
2 POSTS

Truck stopped started. Put key in ignition, turn the key and the dash lights up but no starter noise. So initially I thought my issue was the clutch safety switch so I cut the 2 wires and spliced them. That did nothing. But then after a little more patience and turning of the key, miraculously the truck just decides to start like normal. Okay, next day I try to start truck and same problem. No start, but dash lights up. So I looked up how to hot wire truck then do so, I pull the relay and shove wire in it’s place and nice or starts up. Okay, so starting the truck that way got me through a couple days. Now hotwiring the truck does nothing. But occasionally I can get it started through either the hot wire method or sometimes by even the key. I’m stumped. Please help.

Thanks

Apr 6, 2021 at 12:59 PM

KASEKENNY

✓Experienced Mechanic
18,907 POSTS

This could be a number of things but what we need to do is check the voltage at the starter on both wires when this is happening. You should have 12 volts on both wires when cranking the engine. I suspect you will not have 12 volts on the purple wire when this happens.

Here are some guides that will help with this and this issue:

https://youtu.be/dCjmRL3p4Cs

https://www.2carpros.com/articles/how-to-check-wiring

If you do not have 12 volts on the purple wire when cranking the engine then we need to go to the relay and check voltage. If you can jump power from pin 30 to 87 and it cranks then you may have a relay issue assuming you have voltage on pin 85.

Let me know what questions you have and we can go from there. Thanks

Image (Click to enlarge)

Professional Diagram for 2CarPros Members
Click here to log in and view diagram.

Apr 8, 2021 at 8:35 AM

Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.