09 Prerunner Spark Plug Change

I recently completed the spark plug change of my newly acquired Taco. It went fairly easy but it did take about a couple of hours given I have never worked on a Taco. My bear sized hands got scratched up just a little. The driver side got interesting when it came to unhooking the ignition coil harness on that side but I got it done without breaking anything.

This Taco has 213k and by the looks of it the spark plugs have been in there for quite awhile. I replaced them with some NGK Ruthenium HX’s. Before the I swapped them out the motor was sounding kind of like a diesel engine. I also discovered one of the coils was missing the rubber grommet that fits between the valve cover and the top of the coil. The motor sounds 90% quieter than before. Here’s some pictures of the old plugs. They’re pretty worn.

 

I’m willing to bet they have NEVER been changed.
They come from the factory with 2 different brand plugs.
Just like you have pictured.

I don’t know anyone that has put back in the 2 different brand plugs.
I personally like the Denso. So that’s what I use.

Impressive to say the least, those plugs are shot.
But the truck still ran

 

Wow. Given the wear I wouldn’t doubt it. Really appreciate the interesting facts. I disconnected the battery to reset the computer it can relearn the air/fuel ratio with refreshed plugs.

I’ve always been a Chevy fan and have not been attracted to Taco’s and until now. I always thought I was above them . I got the itch and it’s time to scratch.

I’m planning on spending some money on it in the coming year to make it off-road capable. Nothing too crazy. Given how unmolested it is I think it’s a solid foundation.

 

The Tacoma has a good reputation for starting and running.
And up until the 3rd Gen, they were fairly simplistic too.
Nothing special about them. And a basic set of metric tools and you can repair just about everything on it.

 

Yikes! What’s the gap on those plugs?

 

I have a feeler gauge but I’m not sure how to properly use it. I still have them and will try getting those readings.

 

As noted above, those are most likely the original plugs. Astounding to me that the engine still ran, and a testament to how forgiving the engine is.
I can't recall ever seeing plugs that worn out, with such a wide gap.

 

Wow original plugs. 3 are denso and 3 are ngk

 

It’s true. I drive it up from the SF Bay Area up to Eastern WA not too long ago. The little V6 has some balls on it. I used it for about a month with the old plugs. The only thing I noticed that it sounded like a diesel engine which I knew wasn’t right. Now after changing plugs, PCV valve and adding back the missing coil grommet it’s quieted down 90%.

I’m going to hold onto to the plugs as proof of what these trucks are capable of. I surely will not lack on the maintenance. I already have an appointment so the Toyota dealership can go through it and tell me what’s recommended. There’s a oil leak on the passenger side front area right of the valve cover. From what I’ve read it will need a new timing chain gasket which is likely going to be expensive.

 

LOL... you know the plugs are old when you need to measure the gaps with a tape measure instead of a feeler gauge!

 

Do you have any service history for the truck? Seeing original plugs at over 200K does indeed make it likely that other maintenance items have been neglected. All of the fluids of course, including the brake fluid which, if old, has absorbed a good amount of water by now. Read up on changing the tranny fluid, most recommend draining the pan, dropping it and checking the magnets, clean or better yet replace the filter screen then put back in the same amount of fluid that came our or do the level check procedure.

As I recall reading, you may find your oil leak is in a specific location that’s prone to this. If so, you may be able to use a little RTV dabbed on the leak point externally and put off the gasket change for a long time. A couple of people in this situation reported good results with this “hack”. Can you tell how bad it is?

I did all of my fluids shortly after I got the truck, as well as idler pulleys and tensioner bearing. Then the alternator told me in no uncertain terms that it needed to be replaced (froze up, ruined my nice new belt, dagnabbit). Most stuff is easy to do, the biggest potential frustration is a stuck drain or fill plug. You’ve got a couple fewer of those in your PreRunner, so hopefully it’ll all be nice ’n’ easy.

 

I have info that the ATF has been serviced at lear 30-60k miles ago. That will be on the list to get done soon. The coolant was also serviced about 30k ago but will refresh that sooner than later. I checked the diff and it was at least at a solid level and the fluid looked decent but will change it out myself soon. The power steering and brake fluids will also need to be done since I’m not sure when they were done. I’ll likely have the dealership handle them since I’m not so comfortable doing those jobs. I took care of the front wheel hub assemblies last weekend which was fun. It gave me a chance to take a look at the brakes and the other components which didn’t look bad or needed servicing.

There’s a shudder when the transmission goes from 4th to 5th gear. I’ve read in a TW forum that there’s a solenoid that might need and adjustment/cleaning along with a fluid change that takes care of it. Before I spend some bucks on the fun stuff I’m going to need to resolve this. Supposedly it’s common so I’m not that worried.

I’m seriously considering lifting it and lightly armoring the bottom but need to take care of all the maintenance before I make that jump. I knew Toyota trucks were good but now that I have one I look at them with a new found respect.

 

Must be some robust coils to jump a gap that large.