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So I was getting ready to go to Portland and going to get gas for the truck. I have a brand new battery (2 weeks old). The truck started fine (fired right up). About 3 blocks from the house it started stumbling and running like it was missing. The battery gauge was showing about dead center which is just below normal range. I figured I'd pull off to the shoulder...it was showing erratic reading on the tachometer but didn't appear to reflect the actual engine rpm....jumping from 1-2 k on the tach but engine was idling normal. I shut off the truck and when I tried to restart nothing...no clicking of the starter (normal low battery stuff) it did have one click like the relays and switches were activating but nothing after that. I had my wife come by and I tried to use jumper cables on it with no effect...I did get starter clicking when trying to jump it but no actual cranking...it was on there for 5 min with the jumper car engine running. Anyone have any issues like this??? I noticed the stumbling about 3 blocks from the house as I turned on the headlights....the stereo was also turning on and off. After I noticed the strange running I turned the headlights and stereo off.
Some kind of electrical gremlin....please help. Starter? Alternator? Relays? Ignition switch? Fusible Link?
Fuses all looked good... I also tried rocking the truck in gear if the starter was jammed. No Check Engine Light
Last edited by green2man0; 12-02-2016 at 04:55 PM.
Sounds like a bad cable connection somewhere. FIrst thing to do is grab a multimeter and measure your battery voltage right on the battery terminals (not on the cables). Should be close to 12V with the switches off. Next, make the same measurement while an assistant tries to crank the truck. If the battery voltage drops dramatically, or if it's much less than 12V with no load, you've likely got a discharged or defective battery.
If the battery checks out good, keep your negative probe on the minus battery terminal and start measuring the voltage on the positive cables while a helper tries to crank the truck. Keep moving your probe away from the battery and closer to the starter until you find the point where the voltage drops dramatically. That's your bad connection. If you don't find the problem on the positive cables, reverse the procedure by putting the positive probe on the plus battery terminal and measuring the ground connection as you move away from the battery.
Like Ron says ^^^...
Bad connection somewhere. Make sure battery connectors and posts are clean. Good connection means bare shiny metal contacting bare shiny metal
I replaced the negative cable with a larger 4 gauge and soldered a heavier gauge 6 (I think) in place of the 8-10 gauge 3 crimp job the last owner did that goes from the positive to the fuse box on the passenger side fender. I'm putting a charge on the battery now...hooked it up to the meter and was only getting 11.93 volts. Update to follow once the battery is fully charged. If that doesn't work I'll move on to a new positive cable. The negative was frayed out of the rubber coat on both ends and the contact point on the block had alot of grease on it (wire brushed the new one).
Oh and the old 3 crimp wire from the positive to the fuse box was loose enough to move it back and forth slightly
Last edited by green2man0; 12-04-2016 at 03:03 PM.
I think it's the alternator. 12.6 volts when I put it back on. Fired up fine and immediately went to 12 volts. Let it run a bit and it just kept getting lower and lower... I shut it off at 11.8 volts (running) tried holding 3k rpm for a minute and no change. Does that sound right to you guys? If it is the alternator like I think is there an upgrade to do as long as I'll be pulling it out??? Let me know if that sounds right or if you think it may be anything else. Thanks
BTW, what model-year are we talking here? It always helps to specify.
Originally Posted by green2man0
... soldered a heavier gauge 6 (I think) in place of the 8-10 gauge 3 crimp job the last owner did that goes from the positive to the fuse box on the passenger side fender. ...
Oh and the old 3 crimp wire from the positive to the fuse box was loose enough to move it back and forth slightly
Did the "8-10 gauge 3 crimp job" look like this? (Again, it helps when you tell us what truck you have in front of you because we may be thousands of miles away.)
If it did, then it's not a "8-10 gauge 3 crimp job". It's the fusible link wire, and it's there to protect your wiring from overloads / shorts. I suggest you put it back.
You did not say whether you cleaned the battery terminals to bare shiny metal. That matters a lot.
1990 toyota pickup dlx 3.0 ext cab 4wd 5 speed. all terminals are clean, battery is new, ground cable is new, looks similar but the 3 crimp from the positive to the fuse box was for sure a home job...not factory...different wire size and cheap crimp connectors.
there was about 6-8" coming out of the box...looks factory...everything after that to the battery was a non factory deal.
Last edited by green2man0; 12-04-2016 at 07:18 PM.
While there are a handful of other tests you can do; around here the local parts stores will do an alternator test for free. So pull it out and trek off to the store. But first --- the whole point of giving away alternator tests is so they can sell you a new one. So check out the prices first (RockAuto has remans for as little as $70). Then you'll know just how much you're paying for the convenience of going home with a replacement in hand.
If your alternator tests okay, we'll talk about testing the harness.
I tested the ground also...multimeter positive on the negative and negative on the alternator housing and no drawn down...like .01-.02 normal specs(while running). all the alternator connections look good as well...no corrosion or loose wires
Side note....I was really hoping it wasn't the starter...I have headers on the truck and it looks like the passenger side has to come off to do that....which would suck
Last edited by green2man0; 12-04-2016 at 07:03 PM.
If you narrow it down to the alternator, you might want to check out this link http://www.4x4wire.com/toyota/mainte...nator_brushes/ on replacing the alternator brushes (part 27370-35060). Brushes cost about $15.
I looked into that Dallas but I found one for 80$ shipped so I ordered it and it should be here in a few days. Thank you for the link though....It's cold (25 was today's high) here so I didn't want to have to mess with more than I had to.
Here's some pictures of the old alternator...I took it off this morning. I'm no expert but the shaft and brushes defiantly look worn. It looks to be the original Denso Toyota unit. 170,000 miles on the truck
The little chips from the brushes are my fault by the way...I tried to pull them out with a needle nose pliers to check the depth...the camera flash did that for me.
Thanks for sharing the pictures. Looks worn to me too. I have my alternator out, but have not taken apart yet, so will be interesting to compare since similar mileage...1992 with 188,000. You put back a re-man alternator?
I also broke the alternator fuse 80a I think trying to check it.
Here's where I'm at: New battery, New Alternator, New ground wire, All battery and ground terminals are clean
What else could it be, first I need a new alternator fuse...7.5 amp charge fuse is good
Also what's the length of the positive battery cable??? 38in? like the ground or longer
Also is there a special tool for getting the 80a fusable link out???I've broken it to bits trying
Last edited by green2man0; 12-09-2016 at 02:18 PM.
12-02-2016, 04:52 PM
