Need help with possible coil issues

The truck has been shuttering hard and quick (like running over a rumble strip), and more long and drawn out like running out of fuel. Only when it upshifts and is at low rpm with minimal pull. If I gun it, it works fine. I changed the spark plugs, and it is much better, but still shutters at the same times. Not throwing any codes either. I recently changed the fuel pump as well. It ran great for several weeks after that. Not sure if the two are related. The symptoms were different as well. Please help. Thanks in advance.

 

Try cleaning the MAF sensor

 

How? Blow it out? I did try pulling it out, and the engine died. I assumed that meant it was working. But I’ve never tried to clean it.

 

https://www.youtube.com/watch?v=MLDTRHmBKC8

Good idea also do the TB.

 

It doesn't work that way. The MAF sensor measures the amount of air coming in the engine and promts the ECU to adjust the air/fuel mixture. A dirty or failing MAF sensor can cause idle/acceleration delays or issues. You should also change the air filter too if dirty.

 

Just checked the air filter. It’s good. I’m going to clean the TB and MAF. Then I suppose next step is to change the coils. I forgot to mention, it has 235k miles on it. I’ve never changed the coils. Bought it with 86k on it. Likely has never been changed.

 

I cleaned both the MAF and the TB. Both were quite dirty. But still does the same. Is there a chance that the coils are just worn out, only disfunctioning when there is a light pull at low rpms when accelerating? No codes, so maybe all are firing, but not good enough?

Before and after...

 

Auto or manual trans? ever changed the fluid?

 

IMO, it is unlikely to be a coil pack issue, so i wouldnt just throw money at it until you're able to isolate the problem

 

Is it throwing any codes? that's where i'd start

 

Transmission fluid is one thing to check for sure

 

No codes. Automatic. No coil pack. Individual coils.

 

It’s not a transmission issue. It’s hard to explain, but it’s definitely fuel related. I’ve had the same type of issue in all my Fords over the years. It always ends up a coil issue. Even when it shouldn’t be. Weird. ‍♂️

 

I just had this issue with my work truck. It has the same motor as your tacoma. It was rumble stripping while driving at low rpm but slight load but it wasn’t throwing a check engine light. Then on monday I went to start it and the check engine light started flashing finally. Was a cylinder 4 mis fire so I put in a new coil pack and it’s driving good again.

 

So I need to wait till the coil finally throws a code? If I only change one coil, doesn’t that basically ruin all the others in a short time? I’ve always heard it’s best to do all at the same time. Plus, I’m traveling 2,000 miles in two weeks from now. If it is very likely a coil going bad, or more, I think I should change them all. Right??

 

You can change them all if you like. I have heard that about coils but honestly on this truck my boss is cheap so we only do one at a time. So far I have never changed one then had all 5 break within a short period of time. I replaced one two years ago and 2 have given up this year. I am sure the other 3 will give up soon but I am on 359,000 miles so it’s to be expected.

 

That sounds like a good way to do it. But I don’t have much time to wait for a code. I’m leaving a week from Saturday. I may give it a few more days.

Is there any other way to tell which coil is acting up?

 

You could buy one new coil, put it in one cylinder at a time test driving after and seeing if the issue goes away. Time consuming but without a code thats thd only way. Also when you do pop a code don’t be alarmed if it gives you a p0300 and a specific cylinder code. That’s what mine did. P0300 and p0304, changer cylinder 4 coil and all is well now.

 

I like it! I may try this out.

 

Another way to test the coil would be to unplug the connector from the coil while engine is on. If the engine shutters the coil in that cylinder is good. If the engine does not change. Swap the coil out.