Need help diagnosing an issue

I have a 2017 v6 access cab with 97k km on the odometer. I have not done any mods, the truck runs stock-size tires and I have owned it since new. I had just completed a long road trip 1000km+.

I was starting the truck after it had sat for a few days and it turned over but didn't start. After a few tries, it kind of sputtered to life. I have been having some strange problems ever since. It seems to rough start 1/5 times. I took the truck to Toyota dealer after about a month hoping something else would pop up making the issue easier to diagnose but they said nothing was wrong. I've run 2 tanks of seafoam through it hoping it was a clogged injector but it didn't seem to do much.

A few of the things I've noticed.

ROUGH idle. Jumps around and flutters while idling.
30%+ reduction in fuel economy.
No low-end power makes it hard to hold cruising gears
Already present gear hunting is much worse
There is a new clicking sound coming from the driver's side of the engine.
I know this sounds funny but the engine just sounds different. Almost like a diesel idling with an uneven lope.



I am planning on changing the spark plugs in a week. I'm going to put a bore camera down the plug holes and see if one of the injectors is leaking.

Does anyone have any idea of what this could be or what next steps I could take to figure out what's going on?

If I get some suggestions I'll try and keep this thread updated when I'm able to fix the issue.

 

Spark plugs would be a good start

 

X2, and check your battery and its connections.

 

Just out of curiosity, on your trip did you continuously try to squeeze as much gas in the tank as possible after the pump clicked off when filling the tank?

 

Checked the battery and the alternator charging. Doesn't seem to be out of the ordinary.

 

No I just fill until it clicks.

 

It sounds like fuel pressure or spark related. I am surprised there are no codes and the dealership released it back scratching their heads.

 

This thread may help:

https://www.tacomaworld.com/threads/2017-tacoma-ticking-sound.466301/

Specifically this post: https://www.tacomaworld.com/threads/2017-tacoma-ticking-sound.466301/#post-13968605

" said its the spring on the injectors due to the high pressure and they all make this racket."


This site may help too:

https://www.toyoheadquarters.com/threads/2016-2017-tacoma-with-ticking-noise-3-5l.480/

The ticking sound is a result of the self-cleaning direct fuel injection systems activation and is a normal characteristic of normal system operation. No repair is necessary to remedy this condition.

 

Lets hope it's not a valve issue.

Have you had the fuel pump recall done? Have you, or a dealer, replaced the crankshaft position sensor?

Barring those major items, I'd check the battery, clean the throttle body and mass air flow sensor, and then replace the spark plugs.

 

https://www.toyota.com/recall

 

I have a crankshaft position sensor on order as it's not an expensive part. My vehicle isn't listed as requiring a recall but that doesn't mean the issue isn't present. Ill clean the MAF and the TB when changing the plugs.

I'll add the fuel pump to the list.

I'm hesitant to jump to valves as I don't have the smoke usually associated with bad valve seals.


Any other ideas?

 

Plugs and clean before ordering any expensive parts

you may take a very long screwdriver or metal post and hold your ear to the end while placing the tip on the various pumps and pulleys in the bay to try and zero in on where the sound is coming from - how I found my Fd buzzing PS pump

 

So I changed the plugs this weekend and I can't believe how much better the truck drives! All of the strange noises seem to have resolved themselves. I did bore scope all of the cylinders and found they were pretty sooty and the plugs smelled like gas. They were not fouled with oil. Seems like the problem was just old plugs after all. Will probably change them a bit sooner next time haha.

Thanks, everyone for your suggestions. Glad this was an easy fix.

 

Great news!

Now go get yourself some nice aggressive oversized tires, and enjoy the fuck outta your Off Road!

 

o2 sensors can cause that problem. Gas smell and poor mileage.

 

Here is more info on the fuel pump recall.

https://tfltruck.com/2020/10/toyota...-million-vehicles-includes-tacoma-and-tundra/

 

sweet, glad you go it straightened out. Do you ever put your foot to the floor? I give mine the good ole Italian tune up every day on the interstate on-ramps

 

All the time hahaha. Gotta take it to 11 every once and a while.

 

What plugs did you go with and how difficult was the shange? Happy it worked out for you.

 

I ordered the denso OEM plugs. I've heard of people going with NGK plugs but I don't think it would be worth the money.

As for the installation, it took me about 4 hours to do. A lot of manuals tell you to pull the manifold because it's difficult to access the coils. Do not listen. They are lying. Leave the manifold in place and unplug and wiggle the wires around until you can extract the coils and plugs. Treat yourself to a good set of extensions that have the flex ends and you'll be fine. If you are curious you can grab a $20 borescope and stick it down the cylinder to get an idea of what's going on in there. Don't forget the dielectric grease.