Changed spark plugs, now truck shuts off seconds after starting

New to the the site and I’ve searched for threads about this and haven’t found much pertaining to this.

I was working out of town, came home and wife said my Tacoma (2003 3.4l TRD off-road double cab) was idling rough.
I assumed it was old spark plugs so I swapped the spark plugs and my truck would start and shut right off in seconds. I then swapped out my coils and spark plug wires with no luck.
After that I went to try and run a code so I ordered and obdll scanner. The scanner would power on but wouldn’t connect, I plugged it into my my jeep and my wife’s van and it connected to both those vehicles just fine. Checked all my fuses and everything was solid.
The only thing I can think of is maybe it’s the ECU.

If anyone has had this happened or has an idea of what could be causing my truck to shut off, let me know.

Thanks in advance!

 

Air tube from engine to maf (air cleaner) hooked up correctly?

 

Enough gas in tank?

 

Welcome to Tacoma World. The most expensive free membership you'll ever have.

 

Happened to me once when I changed plugs and wires. Turned out to be one of the wires was not seated correctly into the coil pack.

 

Check your ground wires

 

Plenty of gas in tank, I’ve double and triple checked that everything was hooked up correctly. Not saying that it’s still not a possibility since I usually have extra bolts when I swap something out anyways But I feel confident I’ve ruled out bad connections.
Maybe ecu got reset when I disconnected the battery?
Also I noticed when I start it there’s a really strong smell of gasoline. Is it possible that a bad o2 sensor or air/fuel ratio sensor could cause the engine to shut off?

 

Igniter on the passenger fender plugged in all the way?

My truck would randomly stall and it ended up being that it wasn't fully clipped

 

The computer doesn't use the O2 sensor until it's warmed up, so no, the O2 sensor wouldn't cause this problem.

The circuit opening relay (fuel pump relay) will turn the fuel pump on whenever the key is in the START position. To keep the fuel pump on in the ON position the computer needs to know the engine is running. I can't remember if it knows the engine is running by the crank/cam sensor and/or feedback from the igniter. I'm not saying it's definitely this problem, but the way you describe it starting then shutting off made me think of this, that maybe the fuel pump is stopping.

Wulf mentioned igniter but this may be built into the coil packs on the 2003.

Since it was already running rough before the spark plug change it could be something unrelated to spark plugs or ignition.

 

My experiences with your description I’d say maf sensor bad or functioning incorrectly. You can try cleaning it with maf cleaner do not touch the element just spray it with the cleaner on the element ... that don’t work might consider replacement one. Symptoms you describe sounds like maf.. but the computer not linking could be just that scanner not all work on some vehicles sad to say. Keep picking at it. Good luck and let us know...

 

and try checking fuel pressure confirm your getting fuel..

 

Try putting the old plugs and wires back in?

 

I fixed my rough idle on my 2008 by doing a good throttle body clean at the same time as changing my plugs, as for your new issue definetly check for broke or loose wires hoses or something you damaged, some people crack their insulators on their plugs when they tighten them...doubt that would be your issue but never know.

 

Went to take a pic at my igniter and this. Anyone know what may be going on here? I do know that my truck has an aftermarket remote start maybe this yellow wire could be that. Beats the hell out of me

 

I know if my autostart does not sense my truck started the starter gives up, and it senses this by a wire which if my memory serves me right is yellow and in the engine bay somewhere...not sure if that would shut the truck off while running though but who knows

 

Someone cut that wire and connected it to the other wire. I was going to ask about any security systems you have. Maybe you have a kill switch somewhere. Try to trace that wire and see where it goes. Maybe someone can look up what that wire is for from that pin in the igniter.

 

Looks like pin 5. That wire is supposed to go to the ecu. Pin IGT3. Which is the ecu input for the Ignition timing output to Igniter for coil pack #3.

 

If the ECU doesn't receive the signal back that the coil fired repeatedly then the ECU cuts the injectors. This other wire must be tricking the ECU somehow, and now stopped doing whatever it was rigged to do.

 

So that black wire near the connector broke away from the yellow wire with the bad connection/corroded, so just re attach so all three wires are connected again if that makes sense....whoever did the autostart install did a poor connection that corroded, you might have just given it that little final nudge to break it apart. The yellow wire is what the auto start uses to see the pulse to know the engine is running thats why they tapped into there.

 

My god, have these people never heard of electrical tape, shrink wrap or caulk?