Misfiring Cylinder #3 or Slipping Transmission

Clearly in the OP's case something is broke and needs fixing.


You certainly don't want to flush the system, as that could break free particles and they can clog the system or cause further damage, but what is your aversion to putting in some new fluid?

 

Why not simply drain and fill the ATF. In the meanwhile order via Ebay a set of 6 injectors for less than $50. A truck with 240k miles and a questionable maintenance history could stand to use both.

 

ATF drain and fill is a good idea but I would not recommend cheap Chinese ebay injectors...something as important (and not so easy to change out) as your fuel injectors you should spend the $$$ on good quality. Lots of horror stories over those cheap ones on here.

 

It isn't the oil it is the additives they are highly detergent it will clean the deposits off the clutch packs that is the only thing that keeps a high mileage unit moving. If I haven't seen this a hundred times I would say go for it. He has a misfire code not a trans code kind of like replacing a fan belt because the heater motor is squealing. Fix the immediate problem see what happens then move on.

 

I think you have more than one problem. A misfire will cause the engine to run rough, but it shouldn't cause the truck to hesitate like that. Unless that 1 cylinder is causing you to lose enough power that it can't keep up with your demand. Sounds like the torque converter or tranny is slipping as well. But I'd just tackle one problem at a time. Fix the misfire first since there is a code, then tackle whats left.

 

I tend to think your mechanic should be able to diagnose the issue. On the P030 code, it could be a bad fuel injector. Also, I think ignition is worth mentioning as well. If the plugs and wires have not been changed, maybe it is time. An iginition coil could also be the issue. You could swap the suspect coil with another coil. If the error code moves to a different cylinder the coil is the issue. When changing injectors or coils I usually do the full set with an oem name brand.

On the symptoms you describe while driving, it does sound like the trans could be flaring. I have not experienced the issue on my Tacomas, but have had similar symptoms on other vehicles. When you are driving, does it feel like the engine is no longer connected to the wheels?

 

Wow, thanks for all of the responses. This is super helpful.

The engine still feels connected, I guess the best way to describe it is a slight loss of power, like it's lagging behind. I said in my original post that it feels like the back tires are spinning on wet pavement or snow.

 

UPDATE: My mechanic started by pulling out all the spark plugs and noticed that they were very worn and plug #3 had black scoring on it. He replaced all six plugs and now it runs like new again. I'm very happy that solved the issue. Now I suppose the next thing to tackle is the transmission... Here's a picture of what the fluid looks like. It's not the best lighting, but in person it looks almost rust colored. I think this is because of the fluid I added to top it off mixing with the old stuff because before I added anything it looked like engine oil. It seems like the majority of you suggest a simple change and not a flush so I think that's my next move, but I'm also a proponent of "if it ain't broke don't fix it." Thanks for all of the advice!

 

Fluid changes are normal maintenance, the 'if it ain't broke don't fix it' doesn't apply there...not changing the fluid is going to shorten its lifespan. Would be like not changing the differential oil because it runs fine, eventually it's going to crap out on you earlier than it normally would have.

I'm talking about a drain and fill, not a flush...you are correct about not flushing it, but a drain and fill with ATF won't hurt anything and will likely help it.

 

There is likely still the underlying issue of what caused the plug to get fouled up in the first place, especially if ONE plug is way worse than the others. That's not normal.

The fouled plug is a symptom, not the cause...

 

Could a fouled plug be caused by a bad fuel filter? Also, 95% of the time I fill up at 1/4 tank of gas, but maybe four or five times I've let it get to around 1/8 and one time since I've had it the gas light has come on. Could this have caused some sediment or particulates to get sent through the system causing this fouling?

 

I’m not really a subscriber of the “must never let it get below a 1/4 tank” thing, but that couldn’t fowl your plugs anyway. If anything, that would clog your fuel pump. And if your engine was otherwise functioning normally, it wouldn’t just fowl one plug.

 

while you are at it clean the MAF [if not already clean], dirty maf can cause all sorts of buggery with the ecu