DrCreosote

I've been chasing this problem for a while and it is frustrating with the intermittence of it all.

It's a 1990 4Runner 3vze, auto trans. Occasionally it will only click when I try to start it. More often, it will click, hesitate, then crank, but close to 100 degrees and it won't ever get past the click unless I jump start it. It always starts fine with a jump start.

I've replaced the starter twice and the replaced the starter contacts on the new starter at least twice. It has a new battery and new battery cables and terminal clamps.

when it does this, I can fix it in one of two ways: 1) jump start it, 2) when I wait for the outside temperature to drop.

Any help figuring this out is greatly appreciated. I'm hoping someone has encountered this before and can maybe tell me exactly how to fix it.

rustypigeon

When you replaced the battery cables, did you replace the ground cable that bolts to the engine?

Is the click comming from the starter?

Did you do a voltage drop test?

voiddweller

Wow.. That's really weird. The first thing I thought of when I started reading your post was the starter, however if jumping it with a different battery fixes it, I'd look at the battery itself, there is a chance it's not cranking out enough amps to start?

Heat causes battery life to shorten. Check fluid levels in the battery if it isn't a sealed type?

Bad Voltage Regulator?

DrCreosote

the click sounds like it comes from the starter.
Are you talking about the ground between the body and the engine? If that's the case, then no, I did not change that, though it is an interesting thought and an easy next step.

It's on its second battery. O'Reilly's said the battery tested ok, but replaced it anyway. I don't recall if I had the alternator load tested, but I could do that.

Mr.Utah

x2 on the battery. It could be a bad new one.

rustypigeon

I am not too familiar with the 3vze, but on the 22re there is a cable from the battery negative to the air conditioner bracket. This is the main ground cable for the engine.

Do a voltage drop test on your cables before replacing them. No sense in replacing parts that you have not checked. Do a google search on how to do a voltage drop test if you are not familiar with this procedure.

Mr.Utah

I had a similar issue with a Montero. When it got hot, it would not start. Ended up being the starter. I would make sure your connections are corrosion free by taking off the positive and negative cables and clean them up. Then clean the metal mating surface on the motor and starter. Also clean the terminals on the battery so there is only metal cable ends to the lead battery terminal. I have fixed many starting issues by just doing this.

scope103

If jump starting "always" works, it's not the starter (or the contacts). Most likely a problem in the connections from the battery (either to ground or to the starter or both).

The voltage drop test is trivially easy; do it first. Just put your trusty digital voltmeter on the battery. Should read "around" 12.6v (its temperature dependent). If it's around 12.1v or lower, given that you have a new battery, I would suspect a charging problem.

Have someone turn the key to start. (assuming no crank) If the voltage hardly changes, you have an open in your wiring. If the voltage drops below 12v, you probably have a bad battery.

RAD4Runner

We've discussed this before. Same truck, correct?


Toyota screwed up the wiring on this, just like it did the 22RE 86-88.

Current needed to actuate the starter solenoid runs a "convoluted path" (4Crawler's very own words); from battery, back to cabin, through ignition switch, to transmission, through neutral safety switch, back to engine compartment to the starter solenoid. Neutral safety switch and ignition switch contacts are probably corroded/pitted from repeated exposure to 12 Amps for 25 years, and that path is way too long = too much resistance = lots of voltage drop on wires = not enough power to consistently and completely close solenoid contacts at all time = intermittent.

Recommended solution:
Add a starter relay (i.e., 30-amp automotive relay),
Disconnect Blk/Wht wire from neutral safety switch from starter solenoid coil,
Wire Blk/Wht wire of neutral safety switch to positive side of ADDED starter relay so it turns relay on when IG is on and trans in neutral,
Wire supply side of relay contact through 12gage wire , through fuse , to battery.
Wire output side of relay contact to starter solenoid coil.

CHEERS!

DrCreosote

Yes, I was having this problem last summer as well. It is determined to teach me something I am apparently resistant to learning.

As I understand it, the NSS is part of a large switch assembly on the side of the transmission. I took it apart and cleaned it up good and greased it with conductive grease and that was about the time the problem went away, so I sort of suspected that might have been the culprit. After cleaning the contacts, nothing appeared to be too heavily corroded or pitted, but there was obvious wear and a lot of crud buildup.

I'll spend the cool part of the day checking cables and connections and if that looks good, I'll put in the relay.

ThanX guys.

DrCreosote

Rad, just to clarify, the NSS is still going to be an active part of the circuit, but the difference will be the bulk of the current will go through the relay?

If the NSS is already giving me trouble, will I need to replace it as well, or is the problem just that it is trying to manage 25A?

DrCreosote

Update:
I installed the relay, it works perfectly. A really hot day coming up tomorrow, supposed to be 107, so that will confirm all is well.

ThanX guys!

RAD4Runner

[QUOTE=DrCreosote;52276115]Rad, just to clarify, the NSS is still going to be an active part of the circuit, but the difference will be the bulk of the current will go through the relay?[QUOTE]
Correct

If problem is intermittent, good chance NSS will still consistently be able to supply the very low current needed to energize the relay coil.

Awesome! Looking forward to hearing good news.