Hi there... it's been a long time since I've been a regular visitor to the forum, but I'm glad to see that there's still activity! I am reaching out for help and ideas to resolve a fairly recent starting problem I've been experiencing. To provide a comprehensive view of the issue, I'm going to go into detail, please bear with me...

About 6 months ago, in the middle of the day, the car wouldn't start right up. The starter engaged but sounded like it was spinning almost freely without much load, but the car would not start. After a few tries the car started normally and I was on my way. Since then, this has happened about twice a month, but since it always started, I didn't worry too much. It is after all a 12 year old car with 195,000 miles.

About 3 months ago, even though the battery was just a year old, I still went in to AutoZone for them to test it. It's still good and they tested the charging/starting system and everything checked out. So I bought a new starter, and only just installed it last month. But I'm still getting the false start every couple of weeks or so.

This past Thursday, ran out into the car during rain, and the car gave me the same false start, this time it kept cranking but not starting. So I played with turning the key at different intervals and different durations. After two quick twists on the key, so the stater engaged, disengaged and engaged again, all in less than a second, the car quit cranking. Sounded like a dead battery, or something more serious. "Damn!"

Called AAA, battery tested good, but still no cranking. Called for a tow truck. While waiting, tried to crank every 10-20 minutes so see if I could get a start going. Still sounded like a dead battery. After a 3 hour wait, the tow truck came, and I suggested that we try a jumpstart before he actually hooked me up... no problem... while I was getting the cables ready, the driver asked if he could turn on the ignition to see what lights were showing on the dashboard. And what do you know... the G started right up.

After a 40 minute drive home, I shut the car off, and it would not start again. Slow dead battery cranking sounded. After an hour, I tried again and it started up.

Friday... I did not go anywhere but did start the G to move it out of the garage into the driveway. Left it there for a few hours, then back in the garage. Each time I started it and turned it off, and back on again several times to see if maybe the battery was draining quickly. No problem.

Saturday (today) drove to Autozone to pick up sparkplugs, although I currently have NGK Iridiums installed 15 months and 25K miles ago, I figured it couldn't hurt to change them again. Started fine. Stopped at the grocery on the way home, spent about 30 minutes inside. Come back out and... no start... dead battery slow crank. Got a lift home for my Sequoia and brought my multimeter. Battery at 12.55v, after a few tries at cranking again (slow dead battery sounds), the battery is down to 12.2v. So it doesn't seem to be the battery right? Left the G there and will go back in a few hours to try to start again and attempt with jumper cables as well.

Any ideas anyone?


- thought it might have been a problem with the anti-theft chip in my key, so I put my usual key on the rack, and started using my spare key that's looks new... no change.
- looked for codes from the computer, only a P1706 (park neutral switch) that's been on and off for the last 8 years without any outward issues.
- it was suggested that the camshaft position sensor and/or crankshaft position sensor might be the culprits. The car shutting off while driving seems to be a common symptom of this, but I don't get that.

At this point, I've not found any potential solutions from the numerous online searches I've conducted. And to bring the G to a garage for a problem that's as intermittent as this, just frustrates both me and the mechanic, not to mention my wallet.
I do not have a regular mechanic, since I do almost all maintenance myself, so do not know of a good G mechanic anywhere close to me.

If you've spent the last several minutes reading this post, I do appreciate the time you spent doing so. If you can provide the solution, or any ideas that I can try, I would be immensely grateful. Thanks in advance!

 

Update...

4 hours later, and I go to pick up the G. It starts up on the first try!.

The first whirr from the starter sounded a little weak, and then returned to a normal starting sounded, then ignotion. I'm beginning to suspect that the battery may be the culprit, and will get it tested again.

In the meanwhile, I will still welcome any comments or ideas from fellow G35Drivers!

 

All of my dead batteries passed the battery test at Advance Auto,

 

I had a similar problem with my old Infiniti M30 years ago and it turned out to be a a faulty starter relay. I would consider swapping the starter relay located in the IPDM E/R. There should be two or three of the same color relays in the IPDM, swap the starter relay for troubleshooting.

 

Interesting... I will try that. Now I've only got to research IPDM E/R, not sure what that is... but I'm sure Google knows.

Thanks...!

 

chinee, IPDM E/R stands for Intelligent Power Distribution Module Engine Room. In my Coupe, it is located in the battery compartment behind the battery. Mr. Google is indeed the smartest dude I know, but a service manual goes a long way. I would highly recommend one, I picked one up on eBay (CD) for under $9.

The theory behind the relay being at fault is that the coil in the relay heats up after the first start and an open in the circuit occurs until it cools down and the circuit closes again. This is a theory and I hope it solves your problem like it did for me on my M30. The two sections of the service manual you will find info for your problem are the PG (Power Supply,Ground & Circuit Elements) and the SC (Starting & Charging System).

Adios Amigo

 

In response to your new thread "Car won't crank when hot outside", I see in your post that you say you swapped the Start and Ignition relays. Did you swap them with each other? If yes, that is not a good idea because both of the relays are in the same circuit and you simply swapped positions. I have not opened the IPDM to see what the options are but if possible use a relay from a less significant circuit, in this case maybe the headlamp or fog lamp relay if they are the same. I would target both the Ignition and Start relays. In regards to your comment that they are not for sale, I cannot validate this, but there are always junk yards out there. I would prefer new, but if what you say is true, used is a good option.

Another important thing to check is your grounds, from what you are describing, it sounds like you could also have a bad ground or weak contact in the starting system. I would clean and inspect the negative terminals at the battery cable both ends as well as the positive terminals related with the start circuit. The bad connection could be caused by expansion and contraction of materials affected by temperature fluctuations.

 

It's probably a relay: starter, ignition, or maybe fuel pump?

I'd check your ground connections as previously mentioned in my opinion the ground from the battery to chassis is subpar. I replaced mine years ago it deteriorated and was pretty cheap.

 

Chinee - did you every resolve you issue? My G35 is having similar problems - I have gone through a long list of testing and repairs with no resolution. Interested in whether you have found a fix! Thanks - Jim

 

It was simply a bad starter. After driving for a few miles, the starter would get too hot to operate. After cooling down for several hours the car would start again without a hitch. Switched out the starter and there's been no problem since.

 

the idiot who installed my sound system messed up on the grounding job. The battery light and endless surfing of forums was a nightmare. Took it to a pro audio shop and got everything re-wired, and tada all better. I definitely agree with the ground theory.

 

Used to be a very common problem with GM cars with headers. The tubes were so close to the starter they would heat it up so much it wouldn't start the car. Once it cooled off it was fine. Swapping the big block solenoid spring (which was shorter) cured it in mine. But after reading through the symptoms, it sounded exactly what I was going through and immediately thought it had to be the starter.

 

Back ti what this forum was originally started for, does anyone have a link for the switch for purchase. Thanks gents

 

Been frustrating as having the same identical problem. Two mechanics told me starter was not the issue. Can you confirm that the starter fixed your intermittent starting issue?

 

"Two mechanics"?
Take your vehicle to a shop that rebuilds starters and alternators.
They are well versed in both testing and rebuilding.
If you do have a bad starter let the shop rebuild it. They will clean & polish the armature, replace the bearings etc and make it like new.
Don't replace it with some other rebuilt POS

Telcoman