Engine will not turn over

Hello,

Is does sounds like the ignition or neutral safety switch has gone bad. But to confirm the problem we must test for power at the neutral switch and ignition switch. Here is a guide to show you how:

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester

and

https://www.2carpros.com/articles/how-a-neutral-safety-switch-works

I thought I would include the starter wiring diagrams just in case. (Below)

Cheers!

Do not remove the starter to have it tested. That is a lot of work for something that is not likely to be the cause of the problem. Doing guesses like that often causes new additional problems with broken wires and twisted off electrical terminals. They often check fine on the bench when there is no load on them. Remove and/or replace parts only after testing and diagnosis proves they are defective.

You know it is not a starter motor problem if you are not hearing the starter relay click. Battery connections are not the problem if the dash lights are working. If the dash lights go out or the head lights get dim or go out when turning the ignition switch to "crank", then suspect battery connections or starter connections. GM likes to tap off the large battery cable at the starter motor to feed other systems on the truck so if the lights dim or go out, Then check the large starter connection.

For a do-it-yourselfer, a quick check of the starter system is to pop the cover off the starter relay, reinstall it that way, then squeeze the movable contact. The system can be broken down into three circuits, the low, medium, and high-current circuits. If the starter cranks the engine when you squeeze the contact, you'll know the medium and high-current circuits are working and it is the low-current circuit with the neutral safety and ignition switches in it that has the problem. If it still does not crank you will know it is a waste of time to investigate that low-current circuit.

When all else fails check the neutral safety switch.

https://www.2carpros.com/articles/how-a-neutral-safety-switch-works

Please let us know if you need anything else to get the problem fixed.

Here are some more diagrams I found (below)

Cheers, Ken

Electrical problem
1986 Chevy Truck V8 Four Wheel Drive Automatic 130K miles

While driving down the road there was an audible "POP" from somewhere in the front center part of the cab. I believe it was from the firewall since I did not smell or see anything else. The truck immediately had symptoms as though it was running out of gas and died. I pulled over, checked the obvious ie; fuses, battery cables, starter wires. I had to tow the truck home, it was the first time the truck laid down in the 24 years I owned the truck. After arriving at home I realized that everything worked except the 1. emergency flashers 2. radio 3. dash "idiot" lights 3. ignition. Any help would be appreciated. My wife says "SELL IT FOR SCRAP."

Does it crank ok? If so, have a helper crank it, while you visually check for spark at the plugs. Check the voltage feed at the ignition switch, red wires, should be hot, gets feed from battery fusible link.

The truck will not turn over at all. There is no sign of the ignition even being turned over on the instrument panel, gauges and all. I am dead on the side of the road...

Yeah, I'd start by checking feed to the ignition switch. Maybe you can get somebody to help you drag it home, tow rope, or call a tow-truck. Then you can work on it at your leisure.

Electrical problem
1986 Chevy Truck 6 cyl Two Wheel Drive Automatic 150000 miles

I turn the key. It makes a clicking sound, but it will not cranck up. How do I make it start?

Check the battery condition and connections if okay could be one of the following starter,park and neutral switch and ignition switch

I have narrowed it down to either a bad ignition or wire that runs from starter to the key. I know this because I ran a wire from the starter ignition point to the battery and it fired right up. So either wiring is bad or something in the steering column. Any suggestions?

check the fusible links that run off of battery for being burn up see pic

Engine Mechanical problem 1986 Chevy Truck V8 Four Wheel Drive Manual Hello. I have a rebuilt 1986 chevy 1/2 ton 4x4, with a 305 engine. anyway my problem is i flushed and re did the antifreeze. some antifreeze spilled onto the engine and i used a garden hose to wash the engine. now when i turn the key it will not start. I just replaced the ignition module and made sure the inside of the distributor was dry. but i still have no luck..... any ideas??? Oh and before you ask there is plenty of gas in the tank, and i could smell and see a spray of gas into the carburetor. Thanks for your help!

are you getting fire to the plugs?

I got her running. i cleaned and gaped the spark plugs and WD40 on the ends.

Cheers!

I have a 1986 chevy with a newly built 350. The engine itself has 0 miles on it. I got it running but then had some starter problems. I removed my old starter, installed a new one (properly shimmed) and attempted to start. The truck behaves as if i have a dead battery and my voltage guage does read low. however i do know that my battery is good. When i turn the key the starter engages, but then the truck acts like the battery is dead and nothing happens. I'm feeling like somewhere there is a bad connection, but have not been able to locate one. I hope you can give me some suggestions.

[quote:239298790a="Laker160th"]I have a 1986 chevy with a newly built 350. The engine itself has 0 miles on it. I got it running but then had some starter problems. I removed my old starter, installed a new one (properly shimmed) and attempted to start. The truck behaves as if i have a dead battery and my voltage guage does read low. however i do know that my battery is good. When i turn the key the starter engages, but then the truck acts like the battery is dead and nothing happens. I'm feeling like somewhere there is a bad connection, but have not been able to locate one. I hope you can give me some suggestions.[/quote:239298790a]

Check all connections from the battery to engine to starter-do a voltage drop on the cable

Or could be a tight engine that needs help to crank over such as removing the plugs and spraying WD-40 to loosen it up. I just hope its done right rebuilding it. I've seen 283/307/350/454/351/360/390/460 won't even budge when crank over because the rebuilding process wasn't followed accordingly. Its like the engine seiged or frozen stiff.

Good Luck

Good Luck

Electrical problem
1986 Chevy Truck V8 Four Wheel Drive Automatic unknow miles
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When I turn the key all dash messages come up as normal and I can hear the starter solenoid switch, yet the starter and engine will not turn over. It appeared that I had full electrical power before cranking but after, I have no power whatsoever. After a few minutes, power will come back on, but the same thing happens when i try to crank again, i lose power. As if the battery was disconnected. I used a simple voltage detector to check that the battery has power and it does. I have power going to the starter and alternator and a good ground at the battery. I removed the starter and jumped it off the battery and the solenoid seemed to engage the starter throwing out the armature and all. Could a badd starter/solenoid cause the complete loss of elec. power like that? What can i do to fix the problem or even point me down the right path to find out what the problem is?

Do a battery capacity test-disable the ignition -use the starter as a loading device-hook the meter to the battery terminals-now crank engine for 10secs-while you read the meter-it should read 9.6volts or better within that 10secs if not replace the battery.

i have already changed the starter multiple times, the solenoid has also been changed just as many times, changed batteries, even tried a battery from a tractor trailer, checked all wiring and everything is hooked up, changed ignition switch, the motor will roll but not fast enough to create a spark or fire

Did you put all the shims back? Slow crank can be that or timing too far advanced, bad battery cables.

My boyfriends 1986 Chev Sonoma s15 has problems starting. It cranks over and eventually starts smells like its flooded. He replaced the fuel injectors and now it is losing fuel what is going on?

How long since a tune-up? Any applicable mil codes? You can check those, yourself. Use a gage and check fuel pressure.

If it cranks good but won't start, have a helper crank it, while you check for spark at the plugs. Do a compression test.

What do meant by this: He replaced the fuel injectors and now it is losing fuel what is going on? leaking or just using a lot of gas

My husband was jumping his car with his truck and the positive cable touched the truck. It killed the engine right away. There is power on accessory but it won't turn over. What would be the problem?

Check the main fuse under the hood.

Hello,
I am new to the forum and am in dire need of assistance.
My truck is a 98 K2500 standard car 4X4.
I replaced the dash and main wiring harness with a dash and harness from a 97, same model truck.
Every molex plugged directly in. The only difference between the trucks was the 97 had air bags. The yellow (airbags molex) plugs are not plugged in.
Every single thing on my truck works perfectly for the testing, but the truck will not start or even turn over......
Any ideas on what I should check?
The security lights stays on and I tried resetting it, but I have found multiple opinions on how I'm supposed to reset it?
Any help would be greatly appreciated.

Well, on the now crank, you will have to start with power to and through the ignition switch. Then, through the neutral safety switch, and down to the starter selonoid. If you can get it to crank, you will probably have spark and fuel also. You may have to plug in "cheaters" in your air bag connectors. It may be telling the ECM that your airbags are deployed and locking your crank, spark and fuel. I'll have to do a little research on this and get back to you. Question off the top of my head. Why did you have to change wiring harness'? Hope this helps.

James,
Thank you for the quick reply. I'm a custom car builder by trade and I am really stumped on this one.

I purchased the truck used, someone used it as a work truck and the interior was trashed.
The motor and trans were in great shape.

I purchased a new dash for my truck and the wiring harness was integrated into the inner portions of the dash. All of the molex plugs were exactly the same (except for the extra airbag plugs and one black molex), so I went for it. Now the dash is completely in 5 hours+ install time, and the truck will not turn over.
What is really weird is how all of the items on the truck work perfectly, lights ac radio wipers et ect.

I really dont want to tear the new dash out and all apart just to load it with my old harness.

I was able to get the security light to go out by leaving the key on for 15 minutes.
However, the truck will not turn over.

Over the last couple weeks I have some issues getting it started... Mainly when it was really cold. I would turn the key on and have to hold it for a couple secs and turn it on and off a couple times to get the starter to turn over.
Could this be a related problem and coincidentaly gotten worse with the new dash and wiring?

Let's not panic just yet. From the way you describe it, you have a starter or solenoid problem. I would have someone turn the key to start while you test for power at the solenoid (small) wire. If the problem is intermitent, you may have to jury rig a bulb from the solenoid to the inside of the cab so you can see what's going on at the starter. If the light comes on, but no crank, it's got to be the starter. Let me know what you find.

Alright.
I did some testing. I have voltage present on the crank fuse in the fuse panel with the key turned over. I also have voltage on the ignition and ecm fuses with the key turned over.

Per your suggestion, I checked the small red wire at the starter solenoid and do not have voltage when the key is turned over.
I do have constant 12 volts on the larger + positive terminal.

Thanks again for your assistance.

OK, under the hood is a start relay located on the fuse/relay block. This relay works between the key start system and the starter solenoid. If the coil in this relay is weak, it will do as you described. Let me know.

James,
The relay in the fuse block under the hood is not getting power.
Also, I discovered another difference in the two trucks. The one I got the dash from is a manual trans and mine is automatic.

OK, on the wiring harness you installed there should be a 2 wire connector for a clutch switch. If you jumper this whitch out, it should start. If need be, I can give you wire colors, but it should be easy enough to see. Let me know

James,
There is a black molex plug in the vicinity where the clutch would be that did not have anything to plug into. It is black plug, with 2 purple wires, 1 purple/white stripe, and 1 brown/white stripe.

The diagram for a '97 shows a purple and a yellow wire. For a '98, it shows 2 purple wires. Look at the base of the starter relay and see if you have a color match to what you have. The wires go directly to the relay.

Ok,
So the clutch switch wires go directly to the starter relay? The starter relay does have a purple wire on the bottom of it that looks like the coil trigger.

There are two purple wires at the clutch switch molex plug.

So you are suggesting i jumper the purple wires at the clutch switch molex to a 12v ignition wire to act as a trigger?

Just jumper the 2 wires together under the dash at the connector. This will do the same thing as a closed switch. It should start right up.

James,

Ok. On the black molex plug that I assume is for the clutch switch, there are 4) wires. Two purple, one purple/white , one brown/white.

2) wires have 12volts with the key on. I tried jumping each 12v wires to the other side and it would not fire.

If you have 2 wires with 12 volts, key on. Be sure they are only hot with"key on". If only one is hot with key on, this is the one you want to use. Jumper this wire to the purple wire going to the start relay. Does the relay close? If the relay closes, does the engine crank? I'm going to look at a different diagram to see what the other 2 wires are for.
Update: The purple and the Brn/wht wires are for the cruise control. That should leave the other 2 for start relay.

Thank you very much for your help.
You were exactly right. Jumping the left side of the molex purple wire (switched 12V) to the purple /white white did enable the truck to start.

I have a new problem. The automatic transmission does not want to shift out of first. It does park neutral drive ect, but does not shift going down the highway.
When it rains , it pours . :)