Starting issue...battery or starter?

[Party Cat]

Hey all! I have an 03 fx35 125,000 miles here in Hawaii. When I bought the car 2 months ago I went for a test drive then signed the papers and bought the car. Hopped in to drive home and the car wouldn’t start. If would weakly turn over once or twice but not start. Seemed like a bad battery. I had a mechanic next door try to jump it with a mobile kit and then with a new battery (still with wires not replaced). No good. The previous owner said she was surprised and hadn’t had a problem before.

Next day I went back and it started no problem. I had the battery tested by two shops and it shows good. I cleaned the terminals and wires to the terminals with sand paper.

Couple months late have had no problems but have not driven much either. Still it started powerfully every time.

Today it suddenly wouldn’t start. Same as the first time. Would turn once or twice but not start. Ironically I was at a mechanic getting my safety check. They couldn’t jump it either and said let the starter cool off maybe it’s going bad and the heat soak was causing it to act up...waited about 30 min and they got antsy to get my car outta the way. They were too lazy to help me push it and I still wasn’t getting a start just weak turn over and dead clicks. One guy decided to put the bigger jump set to it and try with more amp and we got it started luckily.

I went to the dmv about 10 min drive and waited an hour and got my registration done. Car started just fine after that.

Now I’m wondering if it’s likely the battery or the starter or both? Any thoughts? Much appreciated as always!

 

[kahlilj]

Hey all! I have an 03 fx35 125,000 miles here in Hawaii. When I bought the car 2 months ago I went for a test drive then signed the papers and bought the car. Hopped in to drive home and the car wouldn’t start. If would weakly turn over once or twice but not start. Seemed like a bad battery. I had a mechanic next door try to jump it with a mobile kit and then with a new battery (still with wires not replaced). No good. The previous owner said she was surprised and hadn’t had a problem before.

Next day I went back and it started no problem. I had the battery tested by two shops and it shows good. I cleaned the terminals and wires to the terminals with sand paper.

Couple months late have had no problems but have not driven much either. Still it started powerfully every time.

Today it suddenly wouldn’t start. Same as the first time. Would turn once or twice but not start. Ironically I was at a mechanic getting my safety check. They couldn’t jump it either and said let the starter cool off maybe it’s going bad and the heat soak was causing it to act up...waited about 30 min and they got antsy to get my car outta the way. They were too lazy to help me push it and I still wasn’t getting a start just weak turn over and dead clicks. One guy decided to put the bigger jump set to it and try with more amp and we got it started luckily.

I went to the dmv about 10 min drive and waited an hour and got my registration done. Car started just fine after that.

Now I’m wondering if it’s likely the battery or the starter or both? Any thoughts? Much appreciated as always!

Not sure if it's the same issue exactly, but did you see this recent post?
Fx45 2004 Battery Drain from BCM

 

[Party Cat]

Thanks for that! I did rad that. I don’t have any battery drain though. Most times the car starts no problem on the first turn. Battery seems strong even after not driving for a few days. Only didn’t start twice but similar situation where jumpers didn’t help. On the second time the big booster set (non portable) seemed to give a little extra power and kicked the starter over...

 

[TheMole]

If the battery is new sounds like it could be the starter. Although it trying to turn over makes me think otherwise. Have you checked the voltage at the battery and had the shop do a load test?

Assuming the check engine light isn't on, do you have a code reader to see if there are any pending codes? Reason I ask is because either of the (2) cam or (1) crank position sensors can cause starting issues. I had an ultragauge installed on my previous G35 and there were a couple of times where it took 3 or 4 cranks before it started. Ended up being the left cam position sensor as it threw a pending code when it happened. Just something to look into if it isn't the starter.

 

[Party Cat]

Interesting...definitely not a new battery. Looks like an old weathered battery but tested good twice. Had the code scan many times over the past few weeks so no codes related to that.

I’m thinking the starter is going out and the battery too but wasn’t sure if anyone had experienced both or something similar. Probably start with a battery and see from there as it will eventually need one or if not I’ll have a spare...