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--> HELP<-- Car randomly cuts off, no codes

M45 cuts off randomly and scarcely. Have cat. Codes of p430 and p420 and gear shifter code p1815. Car was brought in dealership 4 months ago for accelerator pedal recall. To note was not cutting off before then. Just started cutting off 2 months after recall replacement. Car will drive a week or two without cutting off. Has stalled on freeway doing 70 and sitting at stop light. Have changed and egr time delay, purge canister solenoid because of emission codes. All emissions codes are gone now. Never power loss, or hesitation normally. Just stalls every so often. Wife can’t drive to work if car is cutting off on freeway .

My first suspect would be a faulty ignition switch but the trouble could be with the ignition system or fuel system also.

as a test. . while stopped and idling . . . just reach over and hit or wiggle the keys .

Infiniti are push start vehicles. It’s a 2006

Trouble codes do not indicate or point to problem. Catalytic converter whether o2 sensor or Cat itself would not cause car to stall, nor would P1815 code. P1815 would cause rough shifting because of relationship to trans but not a stall, however car shifts fine.

Possibly crankshaft or camshaft sensor.

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I thought that but no codes for cam. Also tapped sensor to see if it would fail. I’ve heard it’s possible to be cam sen. With no codes but unlikely.

I’m inclined to agree with @insightful . . . up to a point

A cam sensor will generally not cause a modern car to not start. However, it will take longer to start

A cam sensor can fail after the engine is in operation, and the engine will not stall because of that

This may not be 100% accurate. There may be some exceptions, but I generally feel this is correct.

A crank sensor is a completely different scenario. If the sensor is bad, the car will not start. And if the sensor fails while the engine is in operation, it WILL stall

An intermittently bad crank sensor can be a little trickier to diagnose, naturally

And probably 1/2 or more of the bad crank sensors I’ve replaced never generated any kind of code

I also like Cougar’s idea

None of those problems will necessarily generate fault codes

Is there a way to check cam and crank sensors. And what do you guys think the of it being the accelerator pedal position sensor that was replaced in the recall

Personally, I don’t think a bad app sensor would cause the engine to cut out

What often happens is that there will be no throttle response, when you step on the pedal, if the sensor is bad

When it stalls, you coast to the side of the road, then what happens? Does it crank and start right up again and drive normally? Or ? What happens after it stalls out could provide some clues.

I’ve had a couple of cases of intermittent stall-outs in my cars that otherwise were working fine. Here’s what they turned out to be caused by

  • Faulty fuel pump relay
  • Grit-clogged fuel injection system (bad gas)
  • Faulty ignition switch
  • Bad fuel gauge, out of gas

If it won’t start right back up, that would provide a shop the opportunity to decide if it is fuel or spark. If it always starts right back up, one idea is to install a fuel pressure gauge so you can see it while driving. If that goes down right before it stalls, you’ll at least know it has a fuel problem.

I assume it starts right back up again. Its going to be tough to find. That’s what my Riviera was doing and never did find out why and got rid of it. EGR, intermittent ground, ignition switch, fuel pump, pump relay, computer, etc. etc. I used to drive it around at night with a fuel pressure tester taped to the windshield and a test light trying to figure out if it was fuel or electrical.

Lmbo wow Bing! I know your pain. Thankfully when I drive it is fine. It’s not until my wife drives it cuts off lol. Yes it starts right back up

I agree with db though, that when a cam sensor fails the engine will continue to run until it is shut off and then not start. I have had crank sensors go that stopped the car immediately and no restart, and also that gave me a chuggle so I suppose the crank sensor could do it but everything is a shot in the dark. Fuel pump would also be an issue but usually once they start they continue to run but don’t start again. I have had them though cause a stalling like that just driving down the street and the pump would shut off. Cleaning all of the grounds or a computer malfunction, bad connection, etc. Another real possibility is the coil or coil module failing when hot. I have to confess that after doing all these things in addition to the throttle body cleaning, I put a new ignition switch in (on the steering column, not where the key goes or the button), it was OK for a couple months then started again so maybe that was it and a wire or something was shorted out. Most of these things though will not throw a code and will be hard to trouble shoot without just replacing parts. Hopefully someone else will have a better idea but this has come up before. One guy solved it with an EGR.

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If it’s person dependent, then that points again to the ignition switch. She may have more keys attached to her car key. Again, try wiggling the switch, see if the engine cuts off.

OP: you never answered GeorgeSanJose’s questions …

I wish billrussell. She loss the second key few years ago. We have one key per car.

I tested egr by applying voltage. They all work. Actually I bought new ones. Then realized I could test old ones. But even with new egr and canister solenoid had the problem. But in total it only shut off 3/4 times last 4 months. I live in Houston so if not over heating. It’s always 98+ here

Bill, it’s a push button start with no key so there is nothing to wiggle. Tell ya the truth thinking about it, I’m not sure what would be used for the normal ignition switch. Maybe it just signals the computer and by-passes all of the other mechanisms.