Starter runs in accessory position

2016 Tundra: 93,000 miles. Truck is is excellent condition, I never off road, use it to tow a travel trailer and drive it in town maybe 3x/week.
Problem:
Three times in the past 30 days I can start my truck and drive to the mail box about 2 minute drive. Shut the truck off, get the mail and 2 minutes later when I've tried to re-start the truck this happens:
1. the engine cranks but will not start.
2. if I release the key and it returns to accessory position but the starter keeps running.
3 I have to turn the key to off position and try again.
4. The engine has started after 2-4 attempts.

One time it took 3 attempts to get the truck to start.
There are no error codes being reported.
In between these 3 events I've started the truck maybe 50 times without a problem, so this is very intermittent (so far). My concern is this is going to get worse until I get stranded somewhere.

Anyone seen this problem?

thanks,
Dustin

 

Sounds like your battery is going.

Get it tested.

 

I've never had this happen on my 2016. I did have an intermittent problem with my 2014 though.

If not your battery, could it be your ignition cylinder?

 

YEP ^^^.

Or if the battery is over 3 years old (assuming it's a regular ole retail brand battery) just replace it.

 

A bad battery would cause these symptoms?

 

Bad batteries do all sorts of weird stuff to these trucks.

 

First thing that I would test before I diagnose it further.

Starter is cranking, but not turning engine - eventually OP is able to start truck after multiple tries. Doesn't seem anything is wrong with the engine.

 

My truck (2018) was doing all sorts of crazy crap two weeks ago and then my battery went out. I was worried there was something bigger going on that drained my battery. This is a little comforting to know.

 

Thanks for the replies:
I replaced the battery Jan 2021. When this occurs the engine cranks over at normal, full speed. It's not the battery. The engine is cranking but won't won't start.

 

1. This is a mystery
2. The key is more than likely not returning to the ACC position, but to the RUN position. The starter continuing to run is normal, it is a feature known as Crank To Start and all Tundras do this. It is not necessary to hold the key in the START position.
3. Normal
4. This too is a mystery.

I too have encountered something similar. I'm kind of still in the troubleshooting stage though. I've noticed that if I rotate the key from OFF directly to START, the truck will sometimes crank but not start. On the other hand, if I rotate the key from OFF past ACC to RUN and allow the dash indicators to illuminate, then bump it to START and release allowing the key to return to RUN, the engine will start. I have kind of a hypothesis that the ECU needs a moment to "boot up" and doesn't get that moment when going from OFF to START in one motion but does if there's a pause at the RUN position. Maybe I'll try to play with this with a little more focus today....

I'd like to tag @Ruggybuggy to see if he has any feedback on my hypothesis...

 

That's interesting, I didn't know about the "crank to start" feature, so that's normal. With that in mind, my suspicion turns to either the ignition switch or the fuel pump isn't building up pressure at the fuel rail as quickly as it used to. Up till now, when I hit the ignition switch the truck will start within quarter to half a second. Thijs is so intermittent at this point I don't know how to really trouble shoot it and there are no error codes being posted.
I did a google search using the phrase Tundra and "crank to start" and there are numerous hits so I guess I'll just have to sort though all of them for the time being and see what turns up.

Dustin

 

Someone else more familiar with this would have to answer, but I don't think that the fuel system runs until the engine actually cranks. I don't think it "runs" in the RUN position before the engine is actually started. Another thing that I wouldn't be able to answer is how long the fuel system will maintain pressure after the engine is stopped. What I can answer is that after the engine is cool enough to work on and you open a fuel line, you're likely to get a face full of gasoline....

 

The ol' pop the gas cap off thing wouldn't alleviate that?

 

No, I think that the pressure in the fuel system would be maintained between the injector(s) and the pump. The pressure in the tank would be minimal in comparison and would be regulated by the vapor system. If the pressure in the tank were the same as the injection system, I think that you'd get a face full of gasoline any time you tried to fuel up.

 

Ah true. Guess it would be better to yank the relay then crank it up and let it die.

 

So I read about a dozen posts (from my google search) and most all them link back to insufficient fuel at startup. Most articles I've read say fuel pressure in the fuel rail should stay high for at least 10 minutes after the engine is shut off (so testing for a fuel pressure leak would be worth the effort).

One article said that at startup a fuel pump relay starts the fuel pump running (since fuel rail pressure is low) and after engine start up a different circuit is used to keep the fuel pump running until the engine is stopped. Different car manufacturers use different methods to keep the fuel pump running until the engine is stopped..

I think I'll add some fuel injector cleaner on the chance that some gunk is causing a fuel injector to bleed down fuel rail pressure. However, I almost ways buy gas at a Shell station up the street and shell fuel is supposed to have injector cleaner built in.

This article was interesting about how to troubleshoot fuel pump/pressure issues: https://www.counterman.com/understanding-fuel-pump-problems/

thanks for the replies, I guess I'll go stare at the engine for awhile and try and figure out how to proceed.

 

Not many miles on your truck. My Lexus has 180K and would try to start it self at times without the key even in the car. Turns out the wear particles from the contacts in the ignition switch finally saturated the lubricant/grease in the ignition switch and would short the switch. In other words conductivity would happen with the wear particles in the grease between the contacts. How my starter didn't fry is beyond me it sure did stink. Replaced switch and never had an issue that was two years ago.

mine finally got to point where engine would run with starter running. I would pull the ignition fuse to stop the starter but keep engine running.

 

@Ruggybuggy

 

I had a dumb Chevy that would do stuff like that. If it’s not the battery, I would start looking into the ignition switch. Because that’s what it was on my Chevy. I agree with the crank to start feature quote. That’s completely normal. It’s more like a button that will continue to crank for X amount of time whether you’re turning the key or not anymore. A faulty ignition switch can lead to some strange side effects if it’s malfunctioning. Also a bad clock spring can have some strange side effects as well. Confirm all your steering wheel functions are working properly. My clock spring went bad and the only thing that wouldn’t work was the horn. Just throwing that out there

 

Note to file: just because the engine is "cranking" does not absolutely insure that sufficient voltage is getting to the spark plugs.

 

what I suspect happening is he has a bad ignition switch. when it cranks it sends a signal to the starter relay but not the PCM. The PCM is what sends fuel signal. Most sensor only require 5 volts to operate on a car. If sensors required 12 volts the truck would never run.

 

Might not the PCM control the starter? The PCM might be what dictates the Crank To Start duration so that when the PCM gets feedback that the engine is running it can disengage the starter or to continue to run it to it's maximum programed time (I think I've read that it's 10 seconds). I'm not saying I know, but that might seem more logical than the signals for both the starter and the PCM being run through the ignition switch on individual circuits. The trucks are primarily CANBUS.

 

Items 1,2,3 just happened to my 2015 Tundra today, it would not start. It only has 13,900 miles on it. Used my FIXED Diagnostic Tool (ignition key turned to the ON position) to diagnose the problem and received a P1604 Startability Malfunction code. Googled that code and found a possible solution was caused by a "dirty throttle body" from a YouTube video by "Wrenching with Kenny." I disconnected the air cleaner box and cleaned the throttle body using throttle body cleaner and scrubbing with a toothbrush. Then dried with paper towels. Reassembled everything and it started on the 2nd try and runs great now.

 

Interesting, I'll have to check that out. Back in April, 2022, I added 3 cans of fuel injector cleaner to a tank of gas and the problem never occurred again since I first posted this. Since then I add two cans of fuel injector cleaner every 5,000 miles. Now have 113,000 miles. I've wondered about the throttle body. Guess I'll go clean it. Can't hurt.

Since 5.7L engine has SFI fuel injection I think build up in the throttle body could be a problem. If I understand this properly, basically fuel is injected direct into the cylinder, bypassing the intake manifold.
https://www.toyotaguru.us/rav4-car-features/sfi-sequential-multiport-fuel-injection-system.html

This appears to be the video mentioned by gamparano: youtube.com/watch?v=78PnPDi7zCE


thanks for the post.
Dustin

 

Sounds good. Hope it saves you some money on fuel injector cleaner!

Gene

 

For those interested. I cleaned the throttle plate like in the video. It was very easy. On the 5.7L engine, the throttle is in the very front of the engine, easy to access. After 115,000 miles there was very little crud. I used only one paper shop towel and a little carb cleaner. It was a 15 minute task. Given there was very little to remove I doubt this had anything to do with the original problem. Also, my problem only occurred three times over a year ago. So, it remains a mystery.

Dustin

 

My throttle body didn't show a large amount of dirt or crud either, since it only has 13,900 miles and always garage kept. It's my understanding that a small amount/piece of dirt can cause the butterfly valve not to function properly which triggers the P1604 code causing a no-start condition. What puzzled me was that the only way I could get the starter to stop turning was to turn the ignition key to the off position. I've never encountered that before, still not sure why that occurred. At first, I thought it was a starter/solenoid problem but after watching the mentioned video I thought I'd try cleaning the throttle body before messing with the starter. Maybe I just got lucky but it resolved my puzzling no start condition. Trying this simple thing first saved me $ and much frustration. Hopefully it'll do the same for others.

 

My 2014 did the same thing about two months ago after a hot round of golf. The issue seems to be the same as if the chip in the key lost connection with the computer. It too took three attempts to get the engine to start. FYI In the past I tried to start the truck with a key that has not been programmed just out of curiosity to see what would happen. The engine would not start but the starter remained engaged even if you allow the key to return to the ACC/run position. The key has to be in the off position to disengage the starter. This has not happened again since then. My two cents. BTW I did initially unlock the truck with the key verses the remote. May or may not have had anything to do with the issue. I did lock and unlock with the remote and it started.

 

Our trucks have a Crank To Start function. All that you need to essentially do is "bump" the key toward the START position and it will automatically crank until the engine starts or about 10 seconds elapses, whichever happens first. FWIW, ACC and RUN are two different positions of the key in the ignition cylinder.

 

Well, the mystery no start gremlin came back to visit my 2015 Tundra. I played with it (checked fuses and relays) and was able to get it to start for a couple of days but it kept going back to the no start condition. So, I decided to bite the bullet and drive (or have it towed) to the dealership where I purchased it new and let them deal with it. Luckily, I was able to get it started this morning and drove it to the dealership and dropped it off for a diagnostic review. The dealership just contacted me and said that a Service Bulletin was issued in 2017 or 2018 which addressed the P1604 Startibilty Malfunction Code on 2009 and later Tundra's. Apparently this issue is more problematic with Flex-Fuel engines (which I have) and requires a reprogram/reflash of the ECU to fix the problem. They also said that the $200 reprogram fee is covered under warranty, but I still have to pay the $80 diagnostic fee, which is fine by me. I don't have a copy of the Service Bulletin but when I ran a search looking for it, I did run across a Tundra forum site that shows a copy of the first page of a Service Bulletin that appears to address this issue. (See https://www.tundratalk.net/threads/have-you-ever-had-an-ffv-problem.397473/page-6)