I have a 91' 4runner, and for some reason it wont start. This same thing happened last year too. When the whether gets cold, my 4runner wont start up without a jump, but once it has been running for a while and warms up, it starts no prob. Once I leave it onvernight, the same thing happens. Thinking it was just the battery, I replaced it a couple monthts ago, but it didn't solve anything. Any ideas as to why this is happening and how to fix it?

 

Hmm, I'd check and see how many volts the alternator is kick'n out.

 

Does it crank fast and just won't start? Or does it crank slow? If it cranks fast and won't start, check out this thread: https://www.yotatech.com/forums/show...hlight=rdlsz24

Rob

 

Thats just it... it doesnt crank AT ALL. Nothing happens. Its just dead until I boost it.

 

Sounds like your battery isn't holding a charge. I just put a new one in my 87 a couple days ago for the same reason. What are the cold cranking amps of your battery?

 

Connection problem? Cold weather causes metal to contract. If there is a marginal connection at the battery terminals, or on the other end of either battery cable, you may lose the connection in cold weather.

When you jump it, you bypass the battery, enough current flows after start to warm the "poor connection", so the vehicle runs, and restarts until the next significant cooldown.

That is one possibility.

An easy way to check is, next time you have the no-start connection, measaure voltage between the battery terminals, touching only the center posts. Then repeat between the battery cables. Should be identical, and about 12.3-12.7 volts before start.

 

if you dont atleast hear the starter relay click then it sounds like a battery/charging issue. get a voltmeter and check the voltage. make sure that the voltage goes up while its running, which indicates that the alternator is working.

 

The connection like stated above is also a good place to look. Mine also had a broken ground from the battery to the fender. I fixed that but the battery was still not holding a charge.

 

Clean the battery terminals, coat them with a anti-corrosion compound to keep corrosion to a minimum. NCP 2 works well for me.

 

See the following web page for a simple voltage test to help isolate the source of the problem:
- http://www.4crawler.com/4x4/CheapTri...shtml#EasyTest

 

Sweet... thanks a lot... I'll try and fix it and I'll post again and tell you the results.