Randomly shutting off, won't start.

Hello, long time lurker but first time poster.

I've been having ongoing issues with my Tacoma for about a month now. it's a 2016 SR manual with about 59,000 miles on it. It has a few aftermarket things on it like better speakers, subwoofer, amp, a bar light, and spot lights - but all of these things have been on the truck for the past three years I've had it without problems.

The first time I had an issue I had been driving about 30 minutes in the city and came to a stop sign and the truck suddenly cut off, it was like I just took the key out, no sputtering. It took like ten attempts to get it to start back up, it cranked but wouldn't do anything else until finally starting. It was also extremely hot and humid this day so I thought it was possibly a fluke. Eventually it happened again and it was also idling rough, it would jump between 900 and 500 RMPs and the indicator was jolting around erratically like it was getting stuck on something so I made an appointment with the dealership.

On the way to the dealership this happened several more times but I got it started again each time. Eventually I was going about 50mph down a highway and the brake override light came on, the truck died, bump started itself, another time it died just about every light was flashing randomly on the dash, eventually the truck decided to fully die and I couldn't get it to start again so had to get it towed the last five miles to the dealership.

Dealership told me it was a fuel pump issue, I told them I was skeptical that was the issue but trusted they knew what they were doing. I drove home 20 miles without issue, but it just didn't feel right to me. Later in the day I drove it again for a few miles, parked a few hours and drove home. As I parked at my house -backing into a parking spot - the truck died, it would not start again. The truck was towed again to the dealership where they said it was a blown fuse and lose wire that fed several safety features on the truck - this sounded more plausible.

This time I drove it about 150 miles and the brake override light came back as I was driving 50mph down a highway, truck bump started itself, the light goes away. it's still idling rough between 500 and 900 RMPs. I drive it one more time, about 5 miles away to meet a friend, against my better judgement, this issue happens 1 or two more times, but it never completely dies. The truck sits for a few hours and I go back out to start it and as i'm about to pull away the dies, I try to start it intermittently for about a half hour before giving up. The next day the tow truck driver said it started for him.

Now it's been at the dealership for 4 days this time and they still haven't figured out what the issue is. They said it died for them once, but they didn't see the brake override light flash from what they've said. They said they're going through and disconnecting all my aftermarket lights and stereo but curious if anyone else has any ideas, I saw a few other posts with brake override issues but never a solid resolution other than a fuse which they said isn't an issue they've found this time around.

 

yours is a 4 cylinder right? Sounds like it could be similar to the 2016 V6s that had a Crankshaft Position Sensor (CPS) issue early on but I don't think that was common on the 4cyl

I'm curious what others think....

 

Yes, it’s a 4 cylinder

 

My 2016 v6 is not starting yet but I’ve changed the crankshaft position sensor twice and now I’m waiting for a new gas pedal and sensor assembly. After that if it doesn’t work I’m trying the fuel pump.

 

Aftermarket taillights or anything messing with tail/stop lamps?

 

I don’t think the alternator can keep up with all of the extra accessories and the battery has to pick up the slack until it can’t. When the truck shuts off, check the battery with a VOM. It should be at least 12.5 volts.

 

No aftermarket parts. From what I can tell at the moment it’s the gas pedal (throttle position sensor). I’ll know more tomorrow

 

you said the brake override came on. do you drive two-footed?

 

Lol. No, the brake malfunction override is on and now when trying to start the truck it shakes. I’m guessing that the next step is to check the fuel filter and pump. Any other ideas?

 

Was the recall work done on the fuel pump?
I would get it to tech rather than randomly swapping parts,,, that gets expensive and time consuming quick.

GL

 

As far as I know it wasn’t a recall item on mine, but thanks for the advice.

 

Any evidence of a squirrel or mouse nest under the hood? Mine did all sorts of weird stuff after a tree rat decided to have a snack of a few wiring harnesses.

 

No signs of any rodent activity.

 

Got it running but won’t shift above 4th gear. Taking it to the dealership now.

 

Dealership says it will be weeks before they can look at it. Any other suggestions on what to check?