You could have a bad cell in the battery, how old is it? You may want to have someone do a battery load test to check it. I agree you could have a starter issue. That can also be load tested as well. I haven't measured the voltage drop on starting the car but I do have some experience on another car at what point trips a lot of issues with the modules in that car. You mention 10.5 volts which corresponds with that car.

On that car if I try to start the car with a battery below about 11 volts (it varies down to your 10.5 volt value) it will not make any attempts at starting. Slightly above this value it may start but often instantly fails and in the process may actually trip several other things such as the OEM security system. Now enter starting with a charger/starter. If the charger/starter sees a good battery it will back out of the picture when a start is attempted. So the battery has to still be charged up so if the charger/starter backs out the battery voltage has to be high enough to satisfy the system to remain running long enough for the alternator to keep it running. I am curious what happens if I try it on a totally dead battery so it doesn't back out.

I bring this up since I figure that the Infiniti has a minimum running voltage which may well be different for different modules. So maybe when you start your car it starts but you have dropped the voltage down low enough to trip
the modules.

What may point away from the battery is the jump start from your truck, however that may point to a need to look at the negative battery cable and how it grounds to the chassis. The same as well for the positive lead in regard to connection at the starter. Before removing anything check both of these leads, especially the negative which would be common to everything. The reason I mentioned the negative is that it is common to everything on your car and the positive (based on my car) basically splits into several paths and an issue with (short of a short) would not usually affect everything.

Assuming all look good including your IPDM which contaings your starter relay I would move to the starter. Either take the starter all the way out or move it far enough to clean how it contacts with its mounting since it gets its ground there. I am not sure how it mounts. I have had cars with the starter mounted on the bell housing side but most are in contact with the engine block. Make sure there is a good reference ground to the starter, which can be measured under load. Possibly a quick method in the case of the starter is simply to ground it directly for a test.

In any case if the battery is old, then I would consider replacing it to not only to eliminated it now but to keep it from becoming an issue soon.

 

Thanks for the quick reply! Here's an update. My neighbor had a battery load tester, and I checked out the battery. Battery tests good. Well I went ahead and found a new starter here locally and picked it up, in case I need it tonight. Right now the plan is to pull the old one and take it up to an auto parts store to have them test it. If it tests bad, then I'll replace it. I havn't really come up with a plan if it tests good... any ideas while I'm working?

Thanks again!

 

Remember to check the ground to the engine block. Probably ok since the car loads are carried through it by the power source (alternator).

 

So... the starter tested good on the bench. HOWEVER the guy doing the test and multiple friends advised me that even if it did test OK, that it could still be bad as the test is not 100% accurate since it is not under a load.

I went ahead and replaced the starter and so far it seemed that the starting issues disappeared. Starts right up, every time (15 plus tests). The engine and VDC/ slip lights disapeared (probably from battery disconnected). I decided to drive the car up to a restaurant and ruh row... it stalled going about 30 mph! As soon as it did, the all familiar check engine, VDC, and slip lights came on. I was able to coast to a side street where I parked, and started the car. It started right up, no problems! Wierd... it's never stalled before or else I would have been thinking alternator all along... Yes, all my electrical connections have been checked and rechecked. Everything that I touched is back to it's original condition... I also made sure to have both terminals on the battery disconnected while I was working so nothing would short out. Not only does the starter chassis have a good clean ground onto the block, but it even has a secured dedicated ground wire leading back up to the negative terminals on the battery.

Now I'm thinking alternator? What do you think?

 

There is a way of testing the starter under load as well but not easy to do in your case and most bench type test will not. Not sure how the Infiniti starter is designed but on older ones I have dealt with there is a bushing front and back that can affect them. Basically when I would rebuild one I replaced both of the bushings and would turn the rotor. I then would cut the communtator.

As far as the car stalling you may have to teach it a couple of things such as the idle or the ECM.

Is it idling normally? You may want to drop in and check for codes that may have been generated. It is very possible that it simply lost its 'mind' due to the battery disconnect.

 

It is also possible that there was a high resistance short some where in the wiring that you removed and replaced. Once the connections were re-tightened, all went back to normal. It doesn't take much corrosion to impede the flow of electricity to the starter or solenoid.

 

Have you pulled the IPDM to make sure that it is not corroded? All those lights came on when I had my problems. I have had no subsequent problems with battery or anything else.

 

Where is the IPDM located?

 

On the 2003, it is located right next to the battery (remove cover over battery). On mine, water collected under the battery (no drain) and spilled over into IPDM. Drain under IPDM was clogged hence the corrosion. The IPDM drain is not mentioned (that I could find) in the owner's manual. You have to take off the cover of the IPDM. My mechanic pulled it and it was so corroded that it had to be replaced (big ticket item).

 

Now that I know where the IPDM is, I'll take a look.

So I took the new starter off so I could get my money back. I put the old one back on and the car started just fine. The next day I go to move the car a bit to do some work. It hesitated to start and when it did the entire car shook and the engine ran HORRIBLY. I was terrified and shut off the car. A buddy of mine swore the issue was the cam shaft position sensor. Said he'd seen it before. So I went ahead and replaced it. The car started OK but died within 30 seconds of idling. Not good. Engine light, VDC, and slip light came back.
I'm about done with this, its gotten to be out of my league. I bet it has something to do with the computer...The only thing left I will check is the IPDM box, as suggested. I'm afraid I'm going to have to give in and tow it to the dealer tho... I'm nervous to see the bill...

 

Some of my first thoughts were towards the ECM, however based on what others have said about water intrusion into the IPDM it is fairly easy to see how what you are seeing could be occurring. If the 04 is similar to the 05 then basically all the power to pretty much all the systems you mentioned comes from the ecm relay located in the IPDM.

Are there any modifications on this car, especially grounding kits, aftermarket audio system and so on. Besides the possible issue with the drain plugging up on the IPDM as others have mentioned there have been cases of water entry based on how cables have been run in this area. I used to have some cleaner that I have used on very bad looking circuit boards that would clean them right up, that is before the product was banned. Worked well and if the issue is the IPDM and it having some water damage it is possible that you could fix it. Other wise if the IPDM is the problem you may want to see if you can find a good one at a wrecking yard or other source that doesn't have the same issues. I am a little surprised that the IPDM isn't better isolated from the battery since a failing battery that is gassing off seems like it could cause its own problems with the IPDM.

 

I replaced the cam shaft sensor, same problems...
I ended up giving in and towing it to the dealer (in laws had AAA thank goodness!). $130 just to hook it up to their computer and make a diagnosis. They said it was just a bad cam sensor. Turns out, there's 3. Who woulda thunk it? There's one on passenger side between block and firewall. That's the one I had replaced. There's another one on driver's side same place that's lets visible. AKA "cam sensor bank 2." That's the one that was bad, I had no idea it existed...
There's another one by the air filter supposedly.

Anyway, dealer wanted $450 plus tax to replace the $55 sensor. I said no thanks. I was able to make the repairs in their parking lot and drive off. lol
Works great! Been running great since last night. No check engine lights or anything after unplugging the battery for a while.

Oh, I never did find the IPDM. I have an '04. Different design I guess...

Thanks again guys. I hope my findings will help someone out there.

 

Glad you got it fixed cheaply. One suggestion next time is to post what repairs you have previously done in regards to certain problems. What prompted you to replace the other sensor?

 

So I didn't think I'd be talking to you guys again...

But I'm back!!!

No more issues with that cam shaft sensor... works great. Unfortunately I think I've got a bad alternator now. Let me know what you think.

So I noticed my 2004 G35 sedan had trouble starting a couple times. Just took a little longer. I blamed it on an older battery and the cold temperature. Well, had to get a jump start after running an errand. Started up just fine with the jump. Drove it about 5 miles, and it died. Would not start on it's own. Lights dim, lots of clicking noises.

Since it died on the highway and it was time for a new battery anyway, I ran up to an auto parts store and replaced the battery. I thought it might be a small possibility that it was just a faulty battery, but unlikely. I thought it could at least get me off the highway to a less dangerous place to be stranded.

Well, good news... got me all the way home. About another 5 miles. That all happened on Saturday and it's been sitting in the garage ever since. Tonight is the first time I've had time to mess with it... My first troubleshooting will be to use a meter to determine the voltage of the car while it's off, while it's being started, while it's idle, and while I'm revving the engine. I'm hopping that will answer a lot of questions.

Since it died while running, I instantly thought alternator. Is true or is it a myth that if an alternator is good, that the car should still run without a battery after it has been started?

What do you guys think? Time to go get greasy...

 

Not a myth. That's how I usually check alternators in a pinch. Disconnect the positive lead and if the engine dies, alternator or the connections to the alternator is not functionning correctly. Just do not perform this in wet conditions(especially with the weather now) and never let go of the positive lead as if your alternator is good and you ground out the positive, I really am not certain what would happen but it is likely not to be good.

If you use a voltmeter to measure voltages even with reving the engine, I am not sure if it will increase pass 14.5 volts or so regardless.