Continuing issue with my 2tr-fe

Probably, most cheap generic scan tools will not show you live misfire data.

 

I’m pretty sure the one that’s like $200 from Harbor Freight would read them. Or at least on a Ford.
I no longer have that scanner. So I can’t confirm if it would on a Tacoma.

I’m a bum. I know a guy with a Snap-On scanner.
If I need to use a “good” scanner, I borrow his.

 

Ahhh.. ok.. yeah, the nice one def did.. ill exchange it tomorrow.. I managed to get truck home which is nice because I've been riding my bike 7miles each way to it. Haha.
I pulled codes when I got back and it threw p0304 (4th cylinder) and p0117 coolant temp sensor low voltage

 

Interesting so it sounds like the miss moved, still need to see about the coolant temp sensor circuit though.

 

Any suggestion on how to go about that.. I just replaced the ect.. that's how this all started.

 

If you disconnect the ECT and turn the truck on.
It should read about -40c/-40f

What does the scan tool say your ECT is while plugged in with key on/currently?

 

If you get a scanner that can read live data you can test circuit integrity quite easily by looking at the ECT voltage, with the sensor unplugged it should read about 5v, if you short the 2 pins together it should read 0v.
If it fails either of those 2 tests you have a wiring problem.

 

I will add that a problem with the coolant temp sensor can greatly affect engine performance and driveabilty since it factors heavily into base fuel calculation.

 

Are you sure you replaced the right sensor? Coolant temp for the pcm? Some cars have 2 sensors, one for fuel calculation, one for the gauge. Not sure about those toyota engines

Have you checked all the fuses related to the efi system? Bent pins in the connector? You might have to dig into the pcm connectors, unplug them and do some resistance tests along those wires, see if they're open or shorted

That smell you mentioned in the first post sounds like a super lean mixture out the exhaust

 

2nd gens only have 1 coolant sensor for the ECM, the ECM communicates the temp to the gauge.
That's why I suggested a circuit integrity check using a scan tool.

 

I believe the 5VZ in the 1st Gen had 2 sensors.

I don’t any of the 2 Gen trucks utilized 2 sensors.

 

Yes 1st gens (and many older vehicles) had a separate sensor for the gauge, when high speed module to module communications became mainstream in vehicles most went to single sensors that were read by one module and the data transmitted to the other relevant modules.

 

Just to get clarification.. I would remove the resonator box, run the truck and disconnect coils while the truck is running, correct? By 'set coil circuit codes' you those are the codes that can be reset, correct?

 

Yes, depending on where the MAF sensor is you may have to unplug it for the truck to run with the intake hose off.
The idea is to see which cylinders are contributing and which ones aren't.
You should notice a pretty significant drop in engine speed when each one is unplugged, the one(s) that don't change when unplugged are your misfiring cylinder(s).

Yes you can clear any codes that may be set when done.

Did you also see my post about testing the ECT circuit using scan data?

 

I did.. would that be a similar situation.. the intake manifold will need to be off for me to get to the ect

 

I did.. would that be a similar situation.. the intake manifold will need to be off for me to get to the ect?

 

Oh I didn't know you had to have the intake off to access the ECT connector (never had to work on a 2TR), but the engine doesn't need to be running to do any verification tests on that.
You can look at your scan data with the engine cold and see if the coolant temp looks plausible, if it does you may try wiggling on wires while watching it and see if you have a connection issue.

 

$70 FOXWELL NT301 OBD2 Scanner Live Data Professional Mechanic OBDII Diagnostic Code Reader Tool for Check Engine Light

https://www.amazon.com/FOXWELL-NT30...ywords=Scan+Tool&qid=1647978465&sr=8-17-spons
will this one do the trick or do you have a better suggestion for a scanner?

 

The manual says it has a misfire monitor.
How extensive it it is, such as each cylinder? I don’t know.

The cheaper scanners are hit and miss.
Some makes and models have more data support.

If I were you, I would make a separate post and ask “what scanner do you have and will it show individual cylinder misfires?”

I bet there are a bunch of people with different scanners that might help you out.

 

I know this is old but what was your symptoms from coolant temp sensor going bad?