Overfilled oil causing problems

1996 Tacoma, 5VZ-FE engine, V6

The oil was dry on the dipstick yesterday. I check it every couple months, and it was fine before. I added a little, and I ended up adding 1.5 quarts, same oil as it had, 10W-30 high mileage. I may have added past the dipstick's max fill line.

I started it and immediately the engine started shaking badly in park. I drove up the road, and the more gas I put, the more it shook. It felt okay coasting downhill, and at least driveable when level, though I don't know how fast.

The dipstick now indicated the oil was way past the max fill line, more than I expected.
I drained 1.5 quarts back out of the drain plug. But the dipstick still shows max. I don't think I should drain any more, because it was reading below the minimum before I did this.

This morning I tried it again, and it started off shaking badly in park, then smoothed out, then started shaking again, then smoothed, but with RPMs still higher than normal. I tried driving it, and it barely moved, blasting out smoke and no power.

I have an appointment with my mechanic in 4 days.

Is there anything you can tell me?

Should I tow it to the shop to prevent damage from driving it there? It's downhill and level to the shop, about 2 miles.

Edit: Forgot to mention, fault code is P0306, cylinder 6 misfire.

 

Your truck was on the level and the engine had been shut off for at least 10 minutes or longer?

You only Check the oil every few months I check mine every time before it gets used.

It very well may be your Misfire causing your poor running engine.

 

A little over the fill on the dipstick will not cause shaking and missing. You have a different issue.

 

At which point in my steps are you asking about the engine being shut off for 10+ minutes? If you mean before checking the oil level again, yep.

If it isn't already clear, my knowledge level on this stuff is very low! I had to look things up online just to realize where the oil drain plug is.

 

Oh lord, someone accidentally drained the transmission fluid again............

 

Ok, I'm quite capable of doing something dumb like that. I drained out of the big pan in the middle! I'll take a pic and post...

 

Let’s hope not.

Just drain all the oil from the ENGINE.
Start fresh. It’s easier to add oil than drain a little out.

 

Yes. Pictures.

The big one in the middle sounds like the Transmission.

 

I drained the fluid from the bolt right in the middle, in the big flat pan. Is that the transmission fluid?? Yeah, I'm that ignorant. I can pour it back in through the transmission fluid thing on top. Is that okay to do? Then I can see about changing the oil.

That would explain why it looked red and not a clear or brownish color...

 

You are looking for this drain plug.
https://www.tacomaworld.com/threads/3-4l-5vz-1st-gen-oil-change-guide.48136/

 

That’s the transmission.

 

You need to check the trans fluid and fill it back up.

Then drain the ENGINE oil.
Put in 1 quart less than the books says.
Then slowly pour in the last quart.
Check the dip stick frequently while adding the last quart of oil.

Once full, start the truck. Turn it off, let it sit for 10 mins. Check it again.

Do all this while on level ground.

 

Don’t worry man. This isn’t too bad.
Luckily you have a 1st gen. They have a transmission dip stick.

Us 2nd Gen guys don’t have one. It’s a pain in the ass to check the trans fluid.

You’ll be fine. I don’t think you need to take it to a mechanic.

 

Ok,

When I drained the transmission fluid, I poured it into empty engine oil quart containers, which I'm sure had some oil residue left in them. Should I definitely go buy fresh transmission fluid now and use that, or will this stuff be okay to re-use, at least for now?

After that, as far as the oil, would it be reasonable to drain a quart (from the ACTUAL oil this time), check the dipstick, and test drive? Or is that a risky thing to do and I better do a full oil change now before driving again? I haven't done one myself before, but I might be able to get a friend to help with that and the oil filter (which I know would normally be replaced but that's about all I know).

 

Yes, I would go buy some new automatic transmission fluid to fill it back up. I would not try to put the old back in, especially if its wasn't' 100% clean of any other material or fluid.

Hopefully you have another vehicle you can use to get some transmission fluid. You should not drive it at all with transmission fluid being drained/low and oil overfilled.

 

Will do. Now that I think about it, the negligible cost of new transmission fluid to be safe is a no brainer.

 

Yep, in doing that, you basically completed a transmission fluid drain and fill, which is a good thing!! Some mistakes, are not always a bad thing .

Not sure what you planned on using for transmission fluid, but i have had great results with Valvoline Maxlife.

https://shop.advanceautoparts.com/p...0-P?vehicleIdSearch=147212&isAllVehicle=false

Good luck!

 

Your transmission fluid is Dexron III, not expensive.

 

UPDATE -

I got a mechanic friend to help me change the oil (to synthetic) and filter, add some transmission fluid, and add some power steering fluid. Runs better than the other day, driveable, but still running pretty rough when gas is applied, and a burning smell, check engine light still on, and it flashed several times at one point. He confirmed it felt like a cylinder was misfiring like the fault code had indicated.

Leading up to this it has not been burning oil (maybe now it is, with the smell?).

There is an oil leak somewhere, with oil on some parts so the source isn't obvious. Sometime this week I'll bring it to a shop. As per my friend's recommendation I'm using foamy cleaner myself first to clean it up and help the shop find the leak when they look at it. He suggests that the shop will check a bunch of stuff to find the leak and why it's running so rough but it might mean a new engine. I hope not.

Anyway I'll keep reading this thread if anyone has more thoughts to share. Thanks for all the great replies so far.

 

Probably not a new engine. P306 code means that there is a misfire on cyl. 6. It could be one of about 10 or so things. Easy ones- bad spark plug, bad coil pack or wire, bad injector.
The spark plug should be looked at first. It also could be a wiring issue (to the coilpack). hard ones- burnt valve, stuck valves, head gasket leak.