Help me figure this one out. My 3rd gen 4runner with the v6 gave me a bit of a scare today.

I was parked at a store and started the runner this afternoon and it sounded like crap. It wasn't running real rough, but there were a lot of odd sounds coming from the engine. At the same time I noticed the dash brake light was on. I checked the emergency brake and it wasn't engaged. I then pulled over after driving 100 feet or so and popped the hood. The brake fluid was fine but the engine just sounded bad (not a tick, or whine, or any other old engine sound I'm familiar with). I then turned and removed the key to shut off the engine and it kept running. Not dieseling, but just kept running even rougher than before. I turned the ignition again and started it up and the starter turned and the engine started running better, but still bad. I turned it off again and it kept running. This all happened within a few seconds, so I gave it one more try to start her up and shut her down, and then the engine stopped like normal (and the brake light went out). I waited a few seconds and started it up again and then it ran fine. I tried to reproduce the problem a few times now, but it's running perfectly.

I'm just scratching my head over this one. What the heck happened?

 

You need to pull a code for us. That sounds really funky.

That's what happened back in the day when a car had a bad cat. I doubt you have that problem unless you have run leaded fuel recently.

 

Maybe something to do with the ignition system? As in... something that would keep giving the spark plugs a spark... but not a very good one.

 

My first guess is that I have an electrical short somewhere. I may have to invest in the whatchamacallit to pull the code . . . Very strange . . .

 

i thought autozone would pull it for free?

 

Cool. I'll try that first.

 

If your check engine light isn't on then trying to pull a code is useless.

Have you ever gotten a lot of water inside the cab?

Sounds like something electrical, but since the problem is gone, it'll be impossible to locate. Could be the ignition switch, ECU or wiring?

Here's a thought how much aftermarket wiring have you added, could it be you tapped into a wire that shows power when ignition is on and once you turn the key off, some how there is a bleed effect where power is still being supplied to the ECU?

Also check the wiring harness to see if any of the insulation got worn away, to me it looks like the iginition system is getting some source of power. That's the only way it could keep running, basically your spark is controlled by a computer and if it gets no power it can't send the signal to the coils.

 

Bad gas..

 

No water recently. Check engine light never came on. Just the brake light.

I've added a few accessories . . . Lights, winch, compressor, etc. In the cab I only have low-amp power going to the switches, so hopefully I'm not frying anything behind the dash. In the cab I have all the accessories run off relays and the power to the relays comes through a fused power bank. I think I have some dash pulling and bonnet probing to do. I hate electrical bugs . . .

EDIT: I just had a thought. I have constant power going to my CB. I have the 75WXST box located under my center console near the brake lever . . . Hmmmmm??

 

Update: The symptom recurred a couple times recently. I also started having starter problems (normal bad starter symptoms). I swapped in a new starter (a pain in the ass little job) and the truck starts fine and seems to be back to normal. It took me a year, but I think I've solved this case . . .

 

WOW, a year. Interesting issue none the less. Hope that it never happens again.

 

my wife reported this same occurance to me the other day, with the exception of the engine kept running. the brake light and rough running was all see noticed, then all of sudden it went away. i havent had any problems at all when i drive it. if anyone gets a lowdown on this symptom please tell us/me.

 

My 4runner just did this to me the other day. I wouldn't start then when I turned the key back, it kept trying to start???

I was like WTF????

Then TODAY, the truck wouldn't start after work... I waited a few seconds, then BAM it started fine...

I hate to take it to the stealership, but........

 

Seems like there are a few posts about these symptoms. Also starter issues seems to be common.

https://www.yotatech.com/forums/f2/my-starter-wont-stop-turning-over-help-52387/ - Starter keeps trying to start engine - bad starter
https://www.yotatech.com/forums/f16/possible-starter-problem-help-56874/ - Bad Starter
https://www.yotatech.com/forums/f2/turn-key-click-turn-key-again-vroom-20716/ - Bad starter
There are a lot more if you do a search.

A rebuilt starter is $140 (plus $50 core) and took me around 3 hours to swap. I could probably do it in around 2 hours now that I know how to get the damn thing out of the engine bay (through the wheel well - after disconnecting the brake line that's in the way). Easy enough job for the shadetree mechanic.