2019 Tacoma With RANDOM MULTIPLE MISFIRES

Has anyone ran into this issue?
I was driving on the highway 125kmph and the check engine light started flashing so I pulled over.
Truck went into "Limp Mode" and would not rev passed 2000rpm.
After sitting and Idling for 1 hr, while i was waiting for a ride, I turned off the truck and turned it back on and the check engine light was off. I still did not drive the truck as directed by Toyota Service.
I had it towed to dealer at this time the the check engine light was now off.
They scanned the system and found the following documents pending:

P030027 - Random Multiple Misfire Detected (Emission) signal Rate
P030085 - Random Multiple Misfire Detected (Over temperature)
P030300 - Cylinder 3 Misfire
P160500 - Rough Idling

They essentially could not duplicate the issue as it was not happening while they had it.
They checked all coil packs and cylinders and said they were fine.
They cleared the computer and I drove it back home, about 800kms, with no issues.
Should I be worried? Maybe Bad Fuel?
Should i take it to my dealer and have them check it or just drive it as i was?
Is this why my truck feels very "gutless" even after the OV Tune because of the weak 3rd cylinder?

Any info is appreciated especially if you have encountered this issue.

 

Misfires are determined by two ways:
1. The VVT sensor motors the individual cylinders.
2. The crankshaft position sensor measures variations in the crankshaft speed. If the crankshaft rotation speed exceeds the predetermined levels, it will flag it as a misfire.

Misfires have a weird logic in Toyota vehicles. Misfire counts are stored in 16 bit binary (max decimal value of 65535) and "normal" for the 6 cylinder engine is 0-600 misfires counted (100 per cylinder).
When a high number of misfires are counted in one cylinder, like your cylinder #3, fuel injection is stopped for that cylinder to prevent the catalyst from overheating.

It looks like all but the rough idle code use a 2-trip detection logic, so this issue did not just pop up, but has been there at least on the trip before you went into limp mode.

I have provided some data to help you with your issue(s). But, Toyota should have done more as these codes store freeze frame data that they could have pulled up and examined.

 

Loose spark plug?! #3 is notorious for that

 

Dang you were driving 125k mph

 

Kilometers per hour

 

Many things could trigger this. Definitely keep an eye on it. My last truck had an issue with the catalytic converter which caused it to not be able to rev past a certain RPM and would trigger a multiple cylinder misfire and flashing check engine light. I suspect that isn't the case here, but I wanted to mention it anyway.

It doesn't hurt to have your dealer look at it. Maybe they have access to more data. Worst case scenario they say they can't replicate it.

And your truck feels "gutless" because it is a part-time, direct-injected V6 which is geared for fuel economy. It's not a V8. It's not a sports car. It's not a turbo. More importantly, it isn't supposed to be any of these things. These trucks don't have the low end torque but they do perform well accelerating while already at speed.

 

Something similar just happened on my 2019 TRD Pro 6 speed manual with just over 55,000 miles. I started the vehicle after it had been sitting all day and the engine light came on flashing immediately. It was definitely running rough but no real difference in performance. I drove it a few miles to a car parts store and had it diagnosed with a code reader, it threw these error codes:

P0300, P0301, P0302, P0303, P0304, P0305, P0306. All point to cylinder misfires on all cylinders. I started the car again and the engine light is now off - it seems to be running as it was, but now I’m worried something is definitely wrong. I’ll try and bring it in over the weekend and see what happens.

Any suggestions of what it could be? I’m fairly handy and would like to replace the spark plugs first as it’s probably time. I’ve heard the ACIS (Acoustic Control Induction System) can have a small tendency to break and let the flap fall into the intake. The shaft end may also get logged in the #3 intake/exhaust valve area, as described here:

https://www.toyoheadquarters.com/th...celeration-also-p030027-p030085-p030300.2368/

However, hoping that isn’t the case! Any guidance would be appreciated!

 

A flashing MIL is typically a sign of something very bad. Definitely avoid driving during those situations until you have verified the issue.

P0300 means random/multiple misfires were detected.
P0301 is cylinder 1, P0302 is cylinder 2, etc. A flashing MIL indicates a catalyst damaging misfire has occurred. So what you're seeing is all 6 cylinders are flagging the error (as you stated).

The repair manual mentions low pressure fuel pump. Have you had the recall performed? Just want to rule out the easiest first, especially if it's something you may not need to pay for.

Otherwise, the repair manual points to the PCV hose connections as well as other intake vacuum leaks.

The fact that it cleared itself is a bit odd though and kind of sounds like an intermittent connection. But the repair manual also states that it is a permanent DTC and that it shouldn't clear on it's own (flashing may go away but the CEL should still be illuminated).

I have attached a document to hopefully provide some extra help. A lot of the steps in this document requires Techstream, which you may be unable to perform, but it can at least provide you with further details on what is going on, or what the truck thinks is going on.

 

Excellent information, thanks for passing it along. I’ll definitely get an appointment booked asap with the local dealer and see what they diagnose, apparently they don’t have appointments until May .

I have not yet had the fuel pump recall so I will definitely look at that first.

 

Did the dealer find the source of the issue? I am having the exact same problem.

 

FYI; this guy and OP have not been back in well over a year.
Typical, people come for help, and can't be bothered to type a follow up to help others,,, and possibly the ones that attempted to help them in the first place.
Don't be that guy.

 

Sorry guys kinda late to the party I'm dealing with that issue right now I have a p0300 just did recall on fuel pump, just changed spark plugs, (pass side plugs had sum oil buildup) changed pcv valve, blueish smoke on startup only, and after a long downhill idle, other than that truck seems to run ok other than the smoke n random stalls

 

I’m having same issue…after a long coast downhill when I accelerate it’s sounds like it’s backfiring thru the intake….big puff of blue smoke then it runs fine…runs fine on a flat or uphill….seems like it’s not making a successful transition from Atkinson to Otto cycle via vvt…..did you get a fix?

 

how did you fix it?

 

FYI, P0300 ended up being bad injector as per here