My 2000 chevy silverado 4.8 starter keeps cranking after started but only in park. i disconnected the battery to reset system and checked and cleaned all my ground wires from starter and battery hoping to get lucky but still doing it. Its been through some puddles lately and may have go something wet. Im assuming its either the starter cylinoid or ignition switch but not sure… Anyone have any ideas? Thanks.
I only had that happen to me once after having a new starter put in. I was 1000 miles from home but called the shop and they said if it happened again, they’d have to pull the starter. Never happened again but for sure it was the starter hanging up.
Only in Park? Sounds like the neutral safety switch on the transmission is bad. You’ll need a heat gun to replace it.
Power from the ignition has to pass through the safety switch while the shifter is in PARK, and the path is disconnected when not in PARK, power from the ignition can’t reach the starter solenoid. The safety switch seems to be working correctly so this makes me tend to think the problem is within the ignition switch and it is either defective or out of adjustment. Try turning the switch slightly back towards the OFF position to see if that corrects the issue while the trouble is happening. If that is no help then check the voltage of the START position of the switch while the switch is in the RUN position. If you have 12 volts there then something is wrong with the switch or its’ position adjustment.
Thanks for all the ideas. So i spent the whole day working on it i replaced the whole starter, starter relay and ignition switch and somehow still doing the same thing… I traced the wires all the way too the ignition switch to the starter and all grounds and wires look secure and fine. I dont understand???
Once again, since the starter only remains engaged in Park, and not N or any other gear, it seems the trouble has to be with the neutral safety switch. That switch performs many functions other than only allowing the starter to operate in P or N. That switch has battery voltage to it anytime the key is not off, and a short inside it can cause voltage to feed to a circuit where it’s not wanted, like to the starter.
You are certain the starter is powered up after releasing the key, have you verified this with a test light?
If the park/neutral switch is suspect as mentioned above, disconnect the park/neutral switch and temporarily install a jumper between the input (purple/white wire) and the output (white wire) and start the engine. This will eliminate any cross feeding from the switch.
Testing is much easier than replacing everything.
You can’t just look at and trace the wires to find the kind of trouble you are having. You need to check for voltage and how it is getting to the starter solenoid. You have two places the power may be coming from. Either the safety switch has a problem or the ignition switch is sending power to the START contacts even though the switch is in the RUN position. Using a simple test light probe will show the way to the trouble.
@asemaster: Thanks for the clarification on the safety switch.
I haven’t replaced the switch yet because I’ve been busy but I went down and looked at it And noticed a blue wire is just unplugged hanging from it anyone know what that does and how hard it is to replace on these trucks?
Sorry if I led you astray and it turns out to just be the switch but hopefully you would have needed a starter at some point anyway.
No worries I had the starter tested at oreillys and it was roast too
I wouldn’t replace anything until you have done proper testing to locate where the problem is coming from. Hopefully you have a test light probe to make checks with. If you don’t have one I suggest you get one. They are inexpensive to purchase.
I like asemasters idea on this I had the same problem on a Taurus. Removed the reverse lights fuse & the problem went away. The reverse lights were triggered from the neutral switch and voltage was crossed with the start circuit
Okay how would I properly check if that was my problem? And if it’s not any other ideas? Thanks
Remove the reverse lights fuse, does the start circuit work correctly now?