Ever have one of those moments, while you're working on your junk, when you stumble across something that explains a bunch issues that you've been having with it? I just did! It felt to me that, over the last year or so, my fuel economy and power were not quite at the same level as it once was. I just figured it was due to the fact that running 35's on a vehicle with almost 200,000 klm's on it, that the engine was getting a little tired. Turns out that when I went to replace my spark plugs (after 5 years), all 6 of them were loose!!! 3 of them were so loose that they were covered with soot right up to the plug wire boot and then onto the boot itself! One of the boots was almost vucanized to the plug! Needless to say, it runs a little better now. WooHoo!!!

 

Glad you found that out! I bet it feels like a whole new truck!

You may want to look into replacing the wires and plugs now, sound like they're pretty gummed up.

Fink

 

Yeah that might be an idea... I'll inspect them a little closer in a few weeks when I retorque the plugs again. Thanks!

 

5 years on a set of plugs?

hell my plug wires go out on my '86 at about 3000miles or 5000 miles..

when i say go out, i mean i can pop my hood at night...and i can see arching between the plugs and other metal parts of the vehicle...kinda weird...i thought plug wires were supposed to last for like 30,000 miles?

 

That's insane...they are definitely supposed to last longer than 3 or 5k!

Fink

 

RSPU strikes again!

(Random Spark Plug Unscrewing)

 

They were the 4 post Bosch Platinums that I took out which were, apart from all the soot, in real good shape and I could've reused them too. When I originally installed them I didn't have a torque wrench and was really more concerned about stripping the heads than the plugs comming loose. Live and learn.

 

I've seen this happen on two different 3.4's...you were lucky one of the plugs didnt loosen to the point where it could have ripped the threads right out of the head.

saw that happen on a 4runner about a year and a half ago. shade tree put a new set of spark plugs and wires on, then forgot to tighten the middle passenger side plug. owner brought it in, and when my stall neighbor popped the hood after scanning it, he found the plug out of the cylinder, still in the partially melted ignition coil, with the hold down tab broke off the coil. ended up needing the head replaced from the damage caused...all paid for by mr. shade tree.

 

Imagine what six NGK BKR5EKB-11s gapped to .043 plus a set of NGK TE66 will do for you. It will run like new. Clean the MAF, TB, and IAC while you are at it.

It is always the little things....

 

I've been having coolant bubbling in the reservoir after turning my truck off for the last year. The temp gauge would run slightly hot too. I replaced the cap; it was an after-market that obviously didn't last as long as a Toyota one. Another kicker, the cap I used was a potential original from my '92 4Runner. Everything is running great now!

 

Yea the 3.4 runs a pretty high compression so those loose plugs would have been a big power loss....

I'd stay away from the bosch... but thats just me

NGK FTW

 

Stunning factual advise that's repeated year after year.

 

I finally got my transfer case back together (replaced front output shaft seal) and took my rig out for a spin. Definitely a little more pep overall but where I really noticed the difference was just backing up the driveway. Normally I'd just feather the gas and clutch backing up (due to the slope of the driveway) because if I just let it idle up, the engine would surge slightly like I was tapping the gas with my foot, but this time when I let it idle up it went up the driveway without any change in revs. SOLID!!! Like it was if I had it in a lower gear or something like that! I can't wait to hit some trails now... Come on weekend!!!