My car has been developing a cold start problem- if the car has been running, it starts perfectly. cold it turns over for about 4mins sometimes. I tried jumping it, and it starts right away. My battery had a voltage of 13 volts, and the car runs fine once it starts.

ideas?

b16 crx, daily driver for 2 years. Battery relocated to rear.

 

either a battery problem, and or the relocation problem.

 

I would check the voltage at the coil while cranking, best guess is you have a voltage drop or a grounding issue. You could get a good voltage reading at the battery, but what is the voltage at the fuse/junction box?

"Arm Chair Diagnostics", results may vary

Kirk R

 

99.999% sure you have a bad battery.

Since it starts right up when jumped you are basically taking your bad battery out of the equation and using the jumper car's good battery (or actually it's charging system) to start your car up. That also will rule out the coil issue since it starts period.

Also, the car runs fine once started so your charging system (i.e. your alternator) is fine. When your car is running the battery is used as a buffer for voltage spikes and surges that come from your alternator. You can actually start your car and take your battery out of the car and it'll still run. I highly do not recommend doing this, but it's kinda of a cool thing to see.

Anyway, your battery can have 13 volts in it, but once it's loaded (like starting your car) those volts go away to say around 2 or 3. Definately not enough to start your car. The 13 volts is called a surface charge and once you ask your battery to actually do something it shorts out internally and you have only 2 or 3 volts to work with.

Easiest thing you can do is pop your battery out of your car, or jump start your car and drive it down to either your local shop or a parts store and they can test your battery. Best bet would be go to a battery store like an interstate or Batteries Plus and they can test it, they'll say it's bad and they can sell you a new one. Or if you have access to a volt meter then test it yourself. Put the test leads on your batteries terminals, say you get 13 volts. Try and start your car if the voltage drops to less then 10 volts (this is my personal opinion, other mechanics may say a little lower, or a little higher) your battery is a gonner.

I would honestly bet 5 bucks it's your battery, so just test it. It's free. Good luck man.

 

First check your battery connections. Clean with a little baking soda dissolved in water and tighten (but not overtight). Do the five easy battery checks listed about 1/3 of the way down at http://honda.lioness.googlepages.com...alternatortips

How old is the battery in years and miles? Have many jump starts been done on it? Because draining a battery to the point the car needs a jump start accelerates battery aging. Buying a new battery may be prudent to save wear and tear on your charging system, too. Car charging systems are not designed to charge batteries from dead, and doing so will shorten the alternator's life. Interstate is an excellent brand for Hondas.

 

Wow, thanks for the legit post. Thanks to everyone else too. I'm going to test my battery now. I sort of assumed the same thing about the battery since it starts with a jump, I just didn't want to spend $80 if I wasn't 100% sure.

Thanks again gang.

 

exactly!!
13v is good enough
at work i tested plenty of batteries with good surface charges
but they turned out to have bad cells
take it to autozone get it tested...for free

 

ha! autozone tested my bat like 3 times and told me it was good all three times and so i tested it at a friends house with his little snap on tester and found out it was bad. screw autozone. but yeh,check for the voltage drop when cranking. your battery might just need some water added to the cells.