We heard you like OBD codes so we added codes to your codes

[thinkCooper]

I've got a 2000 SR5 4X4 5 speed, with 120K miles that I've owned since new. It's pretty much bone stock aside from Bilsteins, Tundra front disc conversion and air bags in the rear for helping with towing.

After sitting in the driveway for a few weeks in the Santa Cruz rain, I took it out today and got a flashing Check Engine light. Got the truck back home and threw an OBD reader on it. P0306 (#6 cylinder misfire) was the first reading. Cleared it, added Seafoam to a full tank of fuel, then drove a few miles. The Check Engine light reappeared.

The second OBD reading showed a P0301 (#1 cylinder misfire), a P0300 (multiple cylinder misfire) and the original P0306. Cleared them, drove a few more miles and codes have reappeared and been cleared a couple of times, sometimes just the P0306 popped back up, sometimes the P0301. Once the P0300.

After sleuthing here a bit on the original P0306, that seems to be related to a potential head gasket leak at #6. But seeing as how I've had that P0301, at the diagonal opposite corner of the engine, it feels more likely to be another condition.

For reference I had the timing belt changed this summer along with water pump and thermostat. I did not have the dealer do the plugs/wires/coil packs, so those are original.

Any diagnostic input would be welcome. I love the truck, it's our rPod tow vehicle and sees light duty use, so it's in pretty remarkable shape for a 16 plus year old truck.

At burningman 2016 - with old dusty dude blocking the view of the rig

 

[TheDurk]

16 year old plugs and wires and you're asking for diagnostics? I wouldn't even start on that until I had changed those.What's your mileage?

Look carefully at the old plugs and keep track of which came from where. They can tell you a lot. Post a pic with them numbered if you want some help with that.

 

[LittleCaesar]

+1 with Durk.

Look under the hood when dry. Start the 4runner and look for arching around the plug wires and coils.

I can't believe you have been a member for 13 years and have ten posts. Love the trailer.

 

[thinkCooper]

+1 with Durk.

Look under the hood when dry. Start the 4runner and look for arching around the plug wires and coils.

I can't believe you have been a member for 13 years and have ten posts. Love the trailer.

I'm one of those quiet types, aside from screwing around with industrial flame effects. Wires and plugs are a better starting point than head gaskets...

Edit: now I'm up to 11 posts

16 year old plugs and wires and you're asking for diagnostics? I wouldn't even start on that until I had changed those.What's your mileage?

Look carefully at the old plugs and keep track of which came from where. They can tell you a lot. Post a pic with them numbered if you want some help with that.

120K miles on the rig - should've done plugs before now, but the wires look almost pristine. Looks like a good project for the weekend.

 

[Tyler James Inc]

Woah woah woah- you have 120k miles on the original plugs?! [emoji43] I wouldn't have even ran SeaFoam through before I changed the plugs. Having eroded plugs may have stressed your coils, and that could be causing a misfire. Maybe you'll get lucky, and solve the misfire with just new plugs. I would definitely do new wires while you're at it.

 

[thinkCooper]

Woah woah woah- you have 120k miles on the original plugs?! [emoji43] I wouldn't have even ran SeaFoam through before I changed the plugs. Having eroded plugs may have stressed your coils, and that could be causing a misfire. Maybe you'll get lucky, and solve the misfire with just new plugs. I would definitely do new wires while you're at it.

I'm thinking a full set of new coil packs, wires and plugs are in this weekend's forecast, along with a break in the rain.

 

[amalik]

I'm thinking a full set of new coil packs, wires and plugs are in this weekend's forecast, along with a break in the rain.

This isn't some Ford 2-door hooptie from the 90s.

The coil packs are expensive as you should only go with the OEM Denso's. You don't want to replace 3 of those unless you absolutely have to.

 

[thinkCooper]

This isn't some Ford 2-door hooptie from the 90s.

The coil packs are expensive as you should only go with the OEM Denso's. You don't want to replace 3 of those unless you absolutely have to.

Expensive is relative; are Densos approximately $120 X 3 at the highend maybe?

But the whole hooptie thing has me intrigued...

 

[amalik]

I don't know part number on that. A search will reveal it though.

Do you need plug and wire part numbers? I have them somewheres, but search also does

 

[jgue467]

Flashing CEL?! Pull over.....

...got a flashing Check Engine light. ...

A flashing CEL is Really trying to tell you More than I've got a code to share with you.

The flashing indicates to IMMEDIATLY let off the throttle or continued use will cause significant damage to the engine and/or cats (way too much unburnt fuel is passing thru!).

As others sais sounds like you need a major tune-up before you kill that thing. Luck and enjoy. :cowboy:

 

[mtbtim]

I did not have the dealer do the plugs/wires/coil packs, so those are original.

Dude, what were you thinking not changing your plugs for that long? At most, you should have changed them at 75,000 miles. It's no wonder you're having check engine codes popping up everywhere.

If you keep on treating your rig this way, we're going to have to pull your 3rd Gen Membership Card and give your rig to someone who will take better care of her. I'm sort of scared to ask how well you maintain the rest of your rig. I'm hoping the plugs were just an isolated issue and you actually renew the fluids like engine oil, trans oil, transfer case oil, differential oil, lubricate driveshafts, etc.

 

[thinkCooper]

I don't know part number on that. A search will reveal it though.

Do you need plug and wire part numbers? I have them somewheres, but search also does

Thanks for the offer. I can dig 'em up. Any prefs on plugs? Denso as well?

 

[thinkCooper]

Dude, what were you thinking not changing your plugs for that long? At most, you should have changed them at 75,000 miles. It's no wonder you're having check engine codes popping up everywhere.

If you keep on treating your rig this way, we're going to have to pull your 3rd Gen Membership Card and give your rig to someone who will take better care of her. I'm sort of scared to ask how well you maintain the rest of your rig. I'm hoping the plugs were just an isolated issue and you actually renew the fluids like engine oil, trans oil, transfer case oil, differential oil, lubricate driveshafts, etc.

Been on top of the oily stuff like tranny fluid, diffs, axle seals, brakes, filters, oil changes, etc. Plugs, not so much...

 

[TheDurk]

Thanks for the offer. I can dig 'em up. Any prefs on plugs? Denso as well?

Denso or NGK. Both are OEM. I've used only NGKs since the beginning and have never had a misfire at 170k. But I change every 30k...

I use NGKs because I use get them at NAPA with plugs for all the machines I maintain. I also run the NGK TE-66 wires.

 

[octanejunkie]

I agree with the consensus to change plugs and wires and do your scheduled maintenance.

A nice NGK wire set is about $28 on Amazon

The genuine Toyota wire set with clips is about $45, if you need the clips

Lots of opinion on plugs. I am running NGKs with good success so far, but may opt for Denso plugs on my next tune up

I'd replace the air filter and clean the MAF Sensor at the same time, then drive it to see if your codes clear

If you do need coil packs, I got Denso 673-1201 Ignition Coils on Amazon for under $59 each

FWIW, I had the same P0300 code along with a few cylinder specific codes. I tried plugs and wires, etc, but the codes went away after I found and replaced a faulty coil pack. Process of elimination and scheduled maintenance.

Best of luck

 

[185Runner]

90919-02212
$86 per pack on camelback

 

[TheDurk]

90919-02212
$86 per pack on camelback

OEM Denso 6731201 $59 on Amazon Prime.

https://www.amazon.com/Denso-6731201-673-1201-Ignition-Coil/dp/B002Y39NFY

or Rockauto for $53 plus shipping.

RockAuto

Same coil. No red box.

 

[JZiggy]

If the plugs really are original, please post some pics!

I changed a friend's plugs on a big ol Mercury something or other with the Ford 4.6 since it was pinging pretty much all the time. The electrodes were worn to complete nubs, easily 3x the factory gap. Fresh plugs made a big difference as you can imagine

 

[Renegade_Medic]

Plugs...

I had no codes, but a distinct lack of power through the mid-range while driving, when I bought my 4runner. It had around 248k miles on the clock. First place I looked was the spark plugs (and wires, hey theyre cheap, why not?). Here is how mine looked. No idea how many miles on them, but the picture speaks for itself.

I don't remember which plugs I used. I think it was NGK. Make sure they are the 2 prong style like this. I have a sticker on my timing cover stating this as well. No need to gap them, obviously.

I'd bet it's a good place to start and unlikely you have a bad head, especially since you have half the mileage I have on mine.
Good luck, the drivers rear is a pain!

 

[Beaumont67]

thinkCooper - Nice looking Gen3, with trailer...gotta love the scooped hood.
Is your hood from Toyota or OEM? Like to get one for my 2000 SR5, but fit must be next to perfect.

NGK Wire Set:
Stock # 4412 || Part # RC-TE66 || A8B6 Made in Japan

Plugs:
NGK Iridium IX Spark Plugs BKR5EIX-11 Part # 5464...think gap is 0.044"