Truck has 190,000 miles. OK, I promise this is happening. First, every now and then the truck won’t start. Turn the ignition key to the start position and nothing happens - like the battery is dead. Turn the key back to the off position, wait maybe 10 - 15 sec. Try and start again - starts right up. This maybe happens about half the time I start the truck. Always seems to start first start attempt of the day. Only later does it start to behave this way. I took it into a repair shop and they claimed it was the starter relay. After the repair (about two weeks) it seemed fixed - started all the time. Then a couple of days ago it began to do the same thing again. Only now, maybe 10 - 20% of the time doesn’t want to crank (vice 50% or more before the repair). Doesn’t seem to be the battery because when it cranks it cranks very strong and starts right up. Now additionally, today, the truck just dies while driving. Doesn’t stall or run rough just before dying - just dies - like turning the ignition switch to off. Interestingly, it starts right back up after this - no extended cranking, etc., just starts right up. I have tried “jiggling” the start switch to see if maybe it is failing, but it has no effect. That is, when the truck won’t crank, “jiggling” the switch won’t make it crank, and “jiggling” the switch while the truck is running doesn’t cause it to die. Sometimes, the waiting 10 -15 secs or so between crank attempts doesn’t work - that is, it doesn’t crank, but if I open up the hood and take the starter relay out of its socket and put it back in, it cranks.
I know, I know, sounds crazy, but I have duplicated this scenario many times. Now, as to the truck just dying, that only started today and I guess maybe has nothing to do with the cranking issue.
The first thing I check when a GM owner complains of an intermittent electrical problem is the side mount battery terminals. Especially the positive terminal.
Remove the battery terminals. And on the positive terminal peel back the red rubber cover to expose the terminals. If you find a lot of corrosion under this red rubber cover, replace the positive battery cable assembly.
I do not know if you are mechanically inclined enough to want to do some testing like jumping the starter stud, but try using only 1 key nothing on a ring for the ignition, changing the steering wheel tilt a bit and see if it helps. I lean twords a failing ignition switch. Just curious how many keys on your keychain?
No worries, I fully believe you. In fact I’ve had problems like this on my 1990’s Corolla before, and the first time it happened all of the following were faulty and in need of replacement
ignition switch
clutch safety switch
starter solenoid contacts
battery
The under-dash starter relay was the only part of the start circuit that was good.
I expect you’ve found one of the problems, but still have multiple problems remaining.
The first thing to do is clean and tighten the battery terminals. If it continues, the best way to address this is to measure the two electrical terminals on the starter motor during attempted cranking. If both measure 10.5 volts or above (measuring terminal to starter case, everything connected), replace the starter motor. If either measures below 10.5 volts, work backwards from the starter motor towards the battery to find out why.
The battery terminals may look clean and free of corrosion, but did you actually remove them and clean them up. Pretty and shiny on the outside makes no difference…it’s the inside that counts.
This sounds like a classic corroded battery terminal problem. And the first thing is making sure the connections are clean and tight. Then move on to the repairs that may cost money.
Without clean and tight connections, none of the other tests listed are even valid.
Battery connections are the first place to begin when you have a “No Crank” situation. Even
if you have a new battery, if the connections are loose, dirty or corroded, you will not be
allowing the full flow of current to pass thru the connections. The connection may be
enough to turn on the lights, but not enough for the huge flow that is needed to operate the
starter. This is where many people say that they know the battery is good….”because the
lights come on”. This is no more a battery test than licking a 9volt battery. It only tells you that there is electricity…not how many volts or the amperage that flows from the battery.
Jump starting may have wiggled the terminal just enough to allow the current to pass and start the engine, but tomorrow you have the same problem.
First remove the cables from the battery and use a wire brush to remove any corrosion and dirt from the battery posts and the cable terminals. There is a tool with a round wire brush for this purpose, found at any auto parts store for less than $10 http://shop.advanceautoparts.com/p/kd-tools-terminal-battery-brush-kdt201/25980576-P?searchTerm=terminal+brush.
Before connecting the cables, apply a coating of di-electric grease to the battery posts this will keep oxygen away from the connection so that it will not corrode as fast.
It is just as important that the other end of the cables also have a clean connection. Remove the positive cable from the battery again so that you do not short anything out. Follow both cables to their far ends, remove this connection and wire brush the connection and the cable terminal clean and retighten these connections.
If there was work done recently, there may have been an “engine to body” ground that was not installed following the work. These grounds normally run from the rear of the engine to the firewall and are uninsulated and most are a braided wire. If any of these are found unattached…reattach them.
Remember….this is not a “Sherman Tank” don’t over tighten the connections.
Tight…tight………………too tight…broke!!!
We have many GM trucks of your vintage in our fleet
And I’ve replaced a few ignition switches for symptoms IDENTICAL to yours
Since you already said your battery connections are clean and tight, I’m not going to dwell on that
I’ve seen a bad ignition switch cause trucks to die cold turkey while driving. No warning whatsover
I also think the crankshaft position sensor is not an issue in this instance . . . because when the truck acts up, you can’t even crank the engine over. A bad crankshaft position sensor would not prevent the engine from cranking over
I just fixed an intermittent starting problem. It would just click three or four times when I would turn the key then it would start I knew the battery terminals were clean. I tested the battery and the starter both tested good the starter sounded dry I thought maybe there was a dead spot on the starter so I replaced it. Then all it would do is click. I was checking the negative cable were it attaches to tranny in this case. the bolt head fell off in my wrench. All this to say check both end of your ground cable.
Here’s a tip: Provided you measure the starter voltages between the terminal and starter case during attempted cranking, that will catch ground problems like this.