Need help diagnosing a sudden vibration/misfire

[wtfemery]

Hi Y’all, I was on the way to fill up today, i was really low on gas (not sure if it’s related but maybe) and i had to go to three different gas stations because each one was not working in some way or another…

anyways as i was pulling up to the last one, i noticed a pretty substantial vibration while accelerating, but not while coasting. After i filled up, I noticed the check engine light came on, and i limped back home at 20mph while the whole vehicle vibrated with the engine RPM’s.

I’d be pretty upset if i’ve clogged a fuel injector or something just because the first gas station wouldn’t just take my freaking card.

Where do I start? Take spark plugs out? I don’t have a code reader. I guess I should order one…

 

[FD7683]

Start off by reading the codes - AutoZone can read them for free if you use their scan tool. If you have 2 misfires, chances are the coil pack is bad but I don't think thats the issue. You might've clogged your fuel injectors because of poor quality gas but you can start off by swapping the coil pack to another cylinder and see if the misfire moves.

Your gas gauge might be off especially if you have a 99-00 4Runner with the TSB EL010–00 problem. Maybe fixing the ground from your fuel pump can fix your gauge issue if you have one (mine did fix the inaccuracy problem).

PhoRunner Channel made a video on the gauge fix: https://www.youtube.com/watch?v=KNbMq7VvpdI

 

[wtfemery]

Start off by reading the codes - AutoZone can read them for free if you use their scan tool. If you have 2 misfires, chances are the coil pack is bad but I don't think thats the issue. You might've clogged your fuel injectors because of poor quality gas but you can start off by swapping the coil pack to another cylinder and see if the misfire moves.

Your gas gauge might be off especially if you have a 99-00 4Runner with the TSB EL010–00 problem. Maybe fixing the ground from your fuel pump can fix your gauge issue if you have one (mine did fix the inaccuracy problem).

PhoRunner Channel made a video on the gauge fix: Toyota 4Runner Gas/Fuel Gauge Fix - YouTube

I think my gas gauge works fine, I filled up with 14.8gal after the light was on for 10 miles.

I don't want to drive it anymore until I know what's wrong (because that always bites me in the ass) so I ordered a scan tool that'll be here monday.

 

[levee-11]

I think my gas gauge works fine, I filled up with 14.8gal after the light was on for 10 miles

You have an 18.5 gallon tank, I'd assume the light shouldn't come on until around 2-2.5 gallons left (Mine comes on at around 3 gallons in the tank, but reads E), or somewhere around there. This means you had 3.7 gallons in the tank still. That seems to me that you don't have a clogging issue, because 3.7 seems like enough fuel to where you aren't purely sucking in the particulate in the bottom of the tank (or the low floaters).

Have you put any additives in? I've ran a concentrated mixture of SeaFoam before, and had it give me a code.

 

[wtfemery]

You have an 18.5 gallon tank, I'd assume the light shouldn't come on until around 2-2.5 gallons left (Mine comes on at around 3 gallons in the tank, but reads E), or somewhere around there. This means you had 3.7 gallons in the tank still. That seems to me that you don't have a clogging issue, because 3.7 seems like enough fuel to where you aren't purely sucking in the particulate in the bottom of the tank (or the low floaters).

Have you put any additives in? I've ran a concentrated mixture of SeaFoam before, and had it give me a code.

no, I was actually considering putting some seafoam in there now though.

 

[brillo_76]

Is the check engine light on? If so, you need to see what the codes are. As if one cylinder isn't firing for whatever reason. They run kinda rough. No power, and your notice the misfiring and possible vibration as well.

I had that happen twice. Once was a bad spark plug. The other time was a coil going bad. If it's a v6. I have a link in my signature to the spark plug, wires and coil thread. The 4 cylinder information needs completed.

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[thezentree]

You need a code reader, there are some cheap bluetooth ones that work with your phone on Amazon.

That said, mine started doing that crap a few months back. Turns out one of my fairly new spark plug wires went bad. Confirmed by swapping plug wires around and watching the misfire code follow the bad plug wire around.

 

[wtfemery]

ran codes, cylinder 2 misfire

I wonder if this is related to the spark plug blowout that happened last year... That was way more violent when it happened, sounded like my engine exploded. I don't remember which one it was. Had it rethreaded and fixed. It's dark now, though. I'll pull the plug and look around tomorrow.

 

[wtfemery]

Looked closer today, switched #2 and #4 plugs, still #2 misfire. Switched #2 and #4 wires (on both ends, ofc) still #2 misfire.

finally, switched the coils and the misfire moved to #4.

The coil that the shop replaced a little over a year ago is the culprit. It looks just like the OEM Denso ones, but it doesn’t have a sticker on it. Still looks brand new.

The shop never asked if i wanted OEM or knockoffs, but they still charged me $117 for the coil. Kinda peeved about that. But i guess it could be worse.

Ordering a real OEM one now.

Also: Are these two coils the same?

Genuine Toyota (90919-02212) Ignition Coil

Denso- 6731201 DIRECT IGNITION COIL

 

[FD7683]

They are both the same - Toyota uses factory Denso coil packs for many of their cars. I would be cautious about ordering coil packs on Amazon/Walmart though as you could receive a counterfeit part. RockAuto has the Denso coil pack for a couple more bucks in shipping but will be guaranteed you will receive the genuine product. Buying the Toyota one will be a Denso coil pack inside the fancy red/brown box.

 

[wtfemery]

They are both the same - Toyota uses factory Denso coil packs for many of their cars. I would be cautious about ordering coil packs on Amazon/Walmart though as you could receive a counterfeit part. RockAuto has the Denso coil pack for a couple more bucks in shipping but will be guaranteed you will receive the genuine product. Buying the Toyota one will be a Denso coil pack inside the fancy red/brown box.

Thanks, that’s really weird. The link i put for the Denso coil was from Amazon but when I click it now it takes me to walmart… I went and checked the comment and it’s still an amazon.com link???

anyways… I’ll order the Denso part from RockAuto

 

[brillo_76]

I am curious if the old coil that is misfiring meets the factory service manual check as good or bad. Its a resistance check and the link is in my signature.

As its extremely rare, but I have seen a coil check out good and not function properly. Never did figure it if it was just the wire boot or the the coil itself as I was happy to get the situation resolved and just curious at this point.

 

[19963.4lsr5]

I’ve had coils on the low end of resistance on the secondary side work at idle and higher up in the rpm range they would fail and cause a missfire.


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[wtfemery]

I’ve had coils on the low end of resistance on the secondary side work at idle and higher up in the rpm range they would fail and cause a missfire.


Sent from my iPhone using Tapatalk

When i was troubleshooting, sometimes it would idle smooth or a few seconds before it started misfiring again. Couldn’t pinpoint exactly what caused it, but sometimes it would just go back to being smooth for a bit.