imcody

sorry if im not posting this in the correct place im new here.

so here is the problem, i have a 2000 toyota tacmoa and last week it started idling weird. while at a light it would almost stall out and then go into really high RPM's. sometimes it would even just stay in the high RPM's.

today while driving it stalled on my for the first time. it will start up just fine but the moment i apply brakes, put on a turn signal, turn on the headlights or turn on the wipers it dies out. i can start in in neutral and then put it in drive but still the moment i do any of the things listed above it dies.

i then let it idle and it did the almost stalling and then goes into really high RPM's. i applied brakes and they worked, i also tried the turn signals and they worked. i turned the truck off and now it wont even turn over. it comes close but just cant actually do it.

bad ground? wiring? ignition? brake booster? vaccum problem? im so confused on where to start any help will be much appreciated. thanks!

rworegon

Start here ^^^. Dies out? As in stalls and engine shuts down? Are you popping any fuses? Is the check engine light on?

What engine?

BTW, welcome aboard.

imcody

"Dies" as in stalls and Engine shuts down. no fuses are popping. Engine is a 3.4L. It all seems like it's multiple issues somehow. Im unsure of why it would have an electrical problem that would effect the rpms. I've had this truck forty only about 6 months and I honestly don't understand newer trucks very well. I've had an 88 Toyota pickup for the last ten years and that thing was a breeze to work on.

rworegon

Any work been done on the rig recently? Check the ground wires under the hood, dash, kick panels etc.
What have you done so far as additional diagnosis?

imcody

I checked for leaks from the brake booster couldn't really find one checked all the fuses and that's really it. Chasing grounds is gonna be super fun haha! I haven't had to do any work on it since I've gotten it. Has a ton of miles on it but ran great until now. Maybe the guy knew there was a problem. Guess it's mine now. I'll look for grounds tomorrow and get back on here

rworegon

Do the signals, light, wipers, etc. work if the truck is not running? Do they continue to work once the engine dies?
Any aftermarket wiring would be a place to look too.

And, you got my 3,500th post.

TheDurk

First, you need to do an overall check of your battery and charging system. Without a solid, steady 12V+ supply, any modern engine will have heart palpitations.

1. Fully charge and load test battery or swap with known, good battery from another vehicle. A good, charged battery is absolutely essential for any electrical trouble-shooting.

2. Verify 12.5+ volts at battery engine off, 13.5 to 14.5 volts engine running, both with headlights, A/C fan, rear def, wipers, all on and also off.

3. Inspect and clean both battery terminals. Replace if insulation is pitted (means corrosion underneath) or if bolt-on terminals have been added. Don't just look and tug, take 'em off and reattach.

4. Likewise verify engine ground by diagnostic plug and the battery ground on fender wall.

Once that is all done and problem persists, THEN you start looking for a specific cause. Don't do it backwards, you will likely waste your time.

wyoming9

iTrader: (1)

With all that is going on I can not believe the MIL is not on!!

I wonder is the bulb not working??

Yes I too liked my older trucks when I first got my Tacoma same year as yours it is quite a learning curve the diagnostics section alone is quite thick and without at least a code reader your always running someplace to get it done.

No charge light on all the time as well??

It seems to me the electrical system is challenged be it wiring(grounds connections) battery or alternator and the ECM is going into save my butt mode and shutting off the engine.

The fact the MIL is not lit is really not a good sign. ECM about to die the final death causing all sorts of issues when mine quit I had about 6 DTC`s

Be nice to see how this plays out

Good luck

offset442

I have a 2000 Tacoma, I can tell you the interlock system is evil, the brakes, shifter interlock, abs and ecm are all tied into a common sensor line that ties into some other modules as well, I had a similar situation that was causing the ecm and abs, to malfunction when i turned on the head lights or turn signals or when the brake swtich was closed, there was some other symptoms as well, but no stalling however if the problem was worse I could see the ecm register the the brakes as being applied then running off the lookup table when the sensor data doesn't jive. in my case I found the cause to be a leakage current of 1.25 MA was on the common sensor line when no current should have been flowing which put the common line into a "grey" state, i fixed this by grounding the line threw a 10k ohm resistor, the easiest place to do this is at the automatic shifter housing as it ties into the shift interlock switch, I removed the shift inter lock linkage and added the resistor there and the problem has been gone since then (about 7 years now), but I still don’t know where the leakage current came from. I was working in the field 1,300 miles from home so the shunt option was the best i could do at the time, it was not easy finding a circuit board to donate a resistor even, sorry i didn't take the dash apart and test for the offending current source, in your case i thinking its more than 1.25 ma if its closer to 12v then you might have the problems described. the weird thing about 4 gens is that multiple modules tie together with he ecm and can cause all sorts of havoc, just go look at the wiring diagram and your will see what im talking about.

just want to add to find the sensor line, its ited into the brake sensor switch on the pedal above the brake light switch its a n/c push button on a bracket, when you step on the brakes, it it ties the line into 12v and lets the abs and ecm know you are stopping, once you find this line of the secmatic follow it from there

madcanvis

Im with the Durk on this...
Pick the low hanging fruit first:
Battery and it's terminals -> Charging system -> Fuses -> Then chase the grounds