1999 4Runner cylinder issues

[runi9]

https://imgur.com/a/Vr6TC8u

The check engine light is on on my 4Runner and my reader gives me these two codes.

I took it to one person and after a brief look under the hood, they mentioned changing the V/C gasket and spark plugs.

Then, I took it to an actual shop and they said they need me to drop it off (or I can wait there), so they can examine it closely.

The first individual gave me some parts and quotes on costs, but the dealer OEM part doesn't seem to be too much more. I was thinking of just getting these parts:

Engine Valve Cover Gasket | Part #1121362020 | Toyota Auto Parts
Spark Plug | Part #9091901192 | Toyota Auto Parts
CORD SET, SPARK PLUG RESISTIVE W/HOLDER

From reading other threads over the years, I know that some third party parts are the exact same as the OEM parts except for the box. I want to avoid that here, so is there anything like that applicable to my situation and parts above?

 

[spartacus]

306 misfire on cylinder 6. Replace the sparkplugs.
Denso K16TR11, NGK BKR5EKB-11, toyota part 90919-01192
Ngk TE66 wires. once you get the #6 misfire fixed the P300 random misfire will go away.

 

[mtbtim]

I agree with [MENTION=50279]spartacus[/MENTION]. Start off with the most affordable and easy options to fix the issue. The spark plugs and spark plug wires are items that should be replaced as regular maintenance anyway. If that doesn't fix the issue, I'd next perform a compression check of the cylinders and see if the #6 cylinder misfire is due to a compression loss. If the compression is good, I'd next suspect an issue with the fuel injector.

 

[Bad Luck]

I agree with both above, but don't forget to check your coil pack resistance as well if your misfire continues after the spark plugs and wires.

 

[mtbtim]

I agree with both above, but don't forget to check your coil pack resistance as well if your misfire continues after the spark plugs and wires.

Have you heard of coil packs partially failing? Since they perform double duty by giving spark to the cylinder they are located in on the passenger side and then transfer spark via a spark plug wire over to the driver side, I'd expect a double misfire if a coil pack went bad. But, maybe they could still be operating properly to provide spark to the cylinder on the passenger side they are plugged into but failing to send current over to the driver side cylinder. I don't remember hearing about a partial failure with a coil pack.

 

[Bad Luck]

Have you heard of coil packs partially failing? Since they perform double duty by giving spark to the cylinder they are located in on the passenger side and then transfer spark via a spark plug wire over to the driver side, I'd expect a double misfire if a coil pack went bad. But, maybe they could still be operating properly to provide spark to the cylinder on the passenger side they are plugged into but failing to send current over to the driver side cylinder. I don't remember hearing about a partial failure with a coil pack.

I actually experienced this with my last 4Runner. The secondary side of the coil that the spark plug wire attaches to had higher resistance than the other two coils, but was still within spec so I replaced the injectors. Misfire still present after so I replaced the coil pack and that fixed it. I expected both cylinders for that coil to misfire as well, but that wasn't my experience. I think there's to separate coil circuits in the coil pack and just one side failed. It was the original coil with about 210,000 miles on it.

 

[runi9]

I also forgot to mention that there is a strong smell of oil as well because of these two issues. Is that normal?

I assume that the OEM parts I listed are ok since no-one posted that the dealer OEM parts are overpriced and/or the same as any third party part?

 

[Bad Luck]

I also forgot to mention that there is a strong smell of oil as well because of these two issues. Is that normal?

I assume that the OEM parts I listed are ok since no-one posted that the dealer OEM parts are overpriced and/or the same as any third party part?

That's most likely the valve cover gaskets/half moons leaking engine oil onto your exhaust manifold.

 

[mtbtim]

I actually experienced this with my last 4Runner. The secondary side of the coil that the spark plug wire attaches to had higher resistance than the other two coils, but was still within spec so I replaced the injectors. Misfire still present after so I replaced the coil pack and that fixed it. I expected both cylinders for that coil to misfire as well, but that wasn't my experience. I think there's to separate coil circuits in the coil pack and just one side failed. It was the original coil with about 210,000 miles on it.

This is good to know that they can fail partially.

 

[runi9]

1. Regarding the possibility of the coils and injectors needing to be replaced also, I suppose the recommendation here is to have the individual guy do the repairs for these two errors since it will be cheaper than the shop, who will also charge a ~$100-200 fee for diagnosing the issue(s)?

2. With the individual guy option, I take it I will not be able to drive the car when the spark plugs and wires are being replaced? If so, then if the plugs and wires don't fix this and I want to try replacing the coil packs and injectors, I'll have to Uber to the dealer to pick up the coil packs and injectors.

3. Is there anything else that can be replaced in the realm of this type of repair job? I would like to update whatever I can since the labor cost is extremely expensive here in Hawaii.

 

[phattyduck]

Regarding coilpacks - first free check coil specs and MOVE the coils around. If the failure moves with the coil, you know the coil is bad.

Do that while you have quality spark plugs and wires on order...

-Charlie

 

[runi9]

Regarding coilpacks - first free check coil specs and MOVE the coils around. If the failure moves with the coil, you know the coil is bad.

Do that while you have quality spark plugs and wires on order...

I'm not sure what this means as I am not doing the repairs.

 

[Michael0789]

had the same codes . . . Denso Fuel Injector Replacement Set for 3.4L V6 4Runner Tacoma and Tundra - HP831 (Naturally Aspirated 5VZ-FE only) | MotorWest Performance these are flow matched and guaranteed injectors. solved all the injector problems. but same code... replaced wires, plugs, and boots, but same code. the 99 compluter can't solve everything. eventually tracked the issue to the throttle body, after fixing that he sounds like a sewing machine. just don't tell him I said so, OK? hope this helps someone, Ciao

make sure you get the injectors for your particular toyota, mine is a 3.4L engine . . .