My car is starting all by itself ! Yikes!

Tom & Ray-

About one month ago my son called me and told me his car ('95 Nissan Maxima) wouldn’t start. After cranking the car it sounded like the starter was bad. I took the starter off and took it to Pep Boys. They tested the starter and confirmed it was bad. I bought a rebuilt starter and came home and installed it with my son. The car started and all was good. The next evening I came home and my son’s car was running in the driveway - locked with no key in the ignition. We took a look at the starter and could see no shorts, or other install errors, etc. That next weekend the car started itslef about 5 times that we know of. I took the car into Pep Boys and after two days they could not get the car to start itself nor diagnose the problem. They indicated that they would replace the starter under warranty but would charge me the labor. I took the car home and the car continued to start itself randomly. This past week I had Pep Boys replace the starter. All was good until I came home yesterday and my neighbor told me that me sons car started itself 8 times yesterday while he was outside. What can be causing the car to start by itself?

Randy M.

Newport News,VA.

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Until you solve this problem, disconnect the battery cable at night. You don’t want to risk a fire. My guess is that the problem is in the ignition switch or the starter solenoid.

A failed starter solenoid could make the starter run but couldn’t energize the ignition, so the engine would crank but not run on its own.

The only thing common to both starter and ignition is the ignition switch.

As JayWB says, what you think is happening is pretty much impossible and the odds against the problem being the starter or your installation of the starter are very high. Two possibilities come to mind.

  1. If the vehicle is equipped with a remote starter, it may be malfunctioning or a neighbor may be activating it inadvertantly while controlling some other device. I don’t know enough about remote starters to know if that is likely or even possible.

  2. If the vehicle doesn’t have a remote starter, I’d look long and hard at the ignition switch. That’s the only place I can think of where electricity to the ignition system and starter solenoid are found in close proximity. I have trouble envisioning how it could fail in a way that would start the car then disengage the starter, but odd things happen sometimes.

I agree with VTCodger.
While I suppose that it is possible for this to be the result of a bad igntion switch, it is much more probable that this car has a remote starter that is being activated inadvertently.

If this car was bought as a used vehicle, there could be many things in its past that you were not aware of when purchasing it, and the presence of a remote starter is just one example. As to what might be activating it, it is anyone’s guess from this distance, but as VTCodger stated, some other electronic device in the immediate area could be triggering a remote starter.

Thanks for the replies. Here’s more to clarify. We have had the car for about three years and never had any issues with the car starting itself UNTIL we put the rebuilt starter on the car in mid May. The car does not have a remote starter. The car has started itself in VA. many times and then again 5 times while my son was visiting friends in Maryland so I don’t think it’s anything triggering the car to start remotely. Sometimes the car will start and stay running… other times it starts and then shuts iteslf off. It started/stopped itself 8x two days ago. I thought the installation of starter may have been the issue because we never had this issue until we installed this rebuilt starter. Now - Pep Boys has “professionally” installed a different starter and the problem persists. I will keep looking for the answer and will update if/when we get this problem fixed.

Thanks for all of your input,


It’s not the starter, since the car cranks, AND runs. It’s the ignition switch, OR, the wiring from it. Some one proficient with a multimeter, and with the wiring diagrams, can fix this. It’s not the starter.
Here is the wiring diagram (Fig. 7) at Auto When you get to the site, register there, come back here and re-click the link. Give the page several minutes to load. Fig. 7 shows the starting circuit. Your electrically proficient mechanic can follow the wiring diagram to the cause of the problem.

To have the starting motor and the ignition system energized at the same time is necessary to crank the car and have the motor start and run. When this happens, how long does the motor run? Does it stop by itself, or does someone have to put the key in and turn it on and then off to stop the motor?

Certainly suspect the ignition switch as the prime culprit. Wiring on these cars is very complex so there maybe a fault somewhere else, bad relay, connector, etc. Don’t see how the starting motor by itself can do this but the wiring to and or from the starter could be where the fault lies.

The remote starter may not be installed now, but my it wouldn’t surprise me to learn that one had been installed in the car at one time and removed or disabled when it stopped working. Perhaps a “backyard” mechanic installed a switch in the car’s wiring somewhere to disable the car and that was done wrong, or has gone bad.

You need to find a very good electrical guy with full Honda wiring diagrams to track this down. Otherwise you may need to rewire the starter circut to include an extra manual switch so you can hit the “off” and disable the starter. Then when you want the car to start you’ll have an extra switch to turn on in order for the starter to crank.

This doesn’t solve your problem and if the ignition is turned “on” by itself the car won’t run. The battery will run down, but at least you won’t be wasting gas.

To have the car start like you stated it surely must have a remote starter system installed in it though you may not have ever used it. I suspect when you worked on the starter the first time you may have disconnected the battery. This may have changed the programming in the unit and is causing it to act like it is now.

One of the wires connected to the starter energizes the solenoid which engages the starter… Put a push-button switch in this wire and use it to start the car…This may be MUCH easier and cheaper than trying to find the fault…

If the vehicle is equipped with a remote starter,

It seems remote starters are the cause of a lot of problems. It would appear that after market remote starters are more likely to fail than not. I would not have one on my car.

And, although the OP insists that the car does not have one, this used car with an unknown history really might have a remote starter. Just because he doesn’t have a key fob for a remote starter does not mean that there isn’t one lying somewhere under the hood, possibly in a location that is not very obvious.

Hi Randy,

10 years later but after a search online I found this thread and thought I’d reach out. I’m having the same issue with a 02 Nissan Altima that I just picked up and was wondering if you ever found the issue or did you just end up getting rid of the car? I told a few people about the issues as well as the car starting itself and they had the same replies until I showed them a video, lol. Also, stalling 8x a day sounds crazy - I’m glad this is just a backup vehicle!

Diagnosis codes picked up a bad camshaft sensor on the car. My research on that leads me to believe that may be the problem because the symptoms are similar, but I’m not sure.

If you have a minute to reply, I’d appreciate it!

Hi, did you solve the problem? I’m having the same one with my car.

Hi Randy, did you solve the problem? I’m having the same one with my car, any advice would be useful.

Today I had to get a jump start for my 1999 Lexus GS300. ( I bought it used, 15 months ago and love it!) Using a power jumper pack, we hooked it up to the battery (with no one in the car, no key in the ignition) the car attempted to start itself. I got in I put the key in to run (not start) and let the car cycle as it tries to run, only for a few seconds, then quit, then try again (ran randomly). did this several times, then just charged as normal (without ‘it’ turning over the starter.) then it did it again. Finally when it was charging as normal I turned it over and it ran as normal. The clock retained time, but I had to readjust the steering wheel.
Weird. I have had to jump-start my Lexus before, and it was a normal affair. This is a real head-scratcher, and only can wonder, does my 99 have a remote start option I don’t know about?

If you start the engine the conventional way, by inserting a keyi nto the ignition switch and twisting it to the “start” position, I doubt remote start is the cause. You car does support a keyless starting system from what I see, don’t know if that’s an option or they all have it. There’s a related tsb: SB0025-14R2. I doubt that’s what’s causing your problem though.

What I think is happening is that the car’s electronics just went haywire for a moment. When an electronics module is denied the power/voltage input expected there’s just no way to predict what it’ll do. If you start getting this sort of problem and the voltage input is correct, that’s something possible to debug. But when it happens when the voltage is low, or during a jump, grin and bear it is about the best you can do.

Change the Relay of your car, it seems that due to rain or something it got wet or drained. I’m sure it’ll help you right away cuz i had the same issue.

Caution folks. This is from 2009. Eleven years ago or so.

Never know, maybe OP is still waiting for help to get it fixed :grin:

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