For the past couple of years I have had a reoccurring problem resulting in a check engine light after following other trucks on dusty roads. I have removed the mass airflow sensor (MAF) for cleaning enough times that the o-ring gasket that goes around the MAF was stretched-out and not sealing. Engine vacuum was drawing dirty, unfiltered air from between the MAF and the intake tube, as evidenced by the amount of dirt around and downstream of the MAF. Eventually the MAF would get dirty enough to build up on the sensor and trigger the check engine light. I always knew before the light even came on that it was happening--engine idle would be fine and low throttle input was also fine, but medium to hard throttle would cause the engine to bog.
Last year I got a check engine light on the trail, so I pulled the MAF out and found the o-ring so stretched, I had to cut it in two, remove a section and use antibiotic ointment from my first aid kit to hold the gasket in place while I reinstalled the MAF. (Hey, it was all I had other than toothpaste!) I later found that Toyota does not sell the 3rd gen 4Runner o-ring gasket separate from a new MAF, which costs somewhere around $150.
I did, however, recently learn that Toyota sells the o-ring separately for the 4.0L V6 4Runners and Tacomas and 4.7L V8 4th gen 4Runners. I did a google image search and found that the MAF for the 4th gens looked the same as the one for 3rd gens. I headed to the Toyota dealership and they were nice enough to try the 4th gen MAF o-ring on a new 3rd gen MAF sensor. It fit perfectly.
The MAF can be removed and reinstalled in well under 10 minutes. The trick is to remove the 3 10mm bolts that hold the cruise control actuator to the passenger fender and fender wheel well and move it aside without disconnecting anything. This provides easy access to the MAF screws, which can easily be buggered up if you're trying to squeeze a tiny screwdriver or 90-degree driver in place. Next, unplug the MAF and remove the two philips head screws that secure the MAF in place. While the MAF is out, spray it down with electrical contact cleaner to remove dirt off the sensor bulb.
The cruise control is the aluminum and white box--in the photo I have already moved it aside:
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Broken o-ring with new one:
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O-ring installed, fits like a glove:
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The MAF o-ring costs $2 and is part number 90099-14141.
Lightbar wiring the hard way. I tried all of the easy ways, such as running the wires down the window channel, but those methods did not give me a clean install. Sometimes the best way to do things is to drill holes. Two of them, in this case.
I elected to use a single cable entry gland to get the lightbar wiring in to the cab.
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Rather than drill three additional holes for mounting screws, I used 3M VHB (very high bond) tape to adhere the cable gland to the roof and also act as a gasket. That has worked great on my Sprinter van solar entry gland.
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The entry gland sits behind the roof track--if the rack were ever removed this wouldn't be super noticeable.
The wiring comes out under the headliner and I have it passing into the C-pillar through a conveniently-located hole. I tried to get the wiring down the B-pillar but the wiring is too thick.
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The wiring for the LedExtreme lightbar is quite thick, partly because it's a dual color version. Because of that I decided it would be cleanest to drill another hole in the floor and route the wiring under the chassis to the two relays and fuse box, rather than route it all through the firewall.
Enter hole 2 in the floor in the recess of the floor pan where the fuel pump wiring is located.
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I had to cut the wiring harness in multiple places. It had to be extended a bit, and other parts cut because they were too long. I used my own switches as well, which meant cutting off the connectors to avoid drilling a massive hole in the firewall to get the wires through.
I dremeled the lower section of the dash to fit the two switches (one for the amber part of the lightbar, one for the white and one for my existing HID fog lights)
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It was time to finally add an accessory fuse block under the hood. I already had my Cadillac horns, ham radio and wideband O2 sensor tied directly to the battery and knew I also had an upcoming air compressor install that would necessitate it. So I added the Blue Sea circuit breaker and fuse block with enough space for a couple of threaded knobs so the aluminum plate could be removed from the factory fuse box if I ever needed to read the printing on the top. (There are nuts JB-welded to the underside of the cover.) I was concerned the screws could loosen on washboard, so I went in later and added a safety pin so the whole shooting match couldn't go anywhere.
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The two relays are mounted in the back corner near the clutch master cylinder.
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And then there was light.
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Complete parts list: Kit
Have fun!
Looks cleaner than you'd find it at the factory....beautiful.
Thanks for keeping this thread updated. I was wondering about the relay used for the horns. My dad used to drive Caddys when I was growing up and I always got a kick out of the way these horns sounded.I like power. And apparently that includes horn power too. I have always been amused by the horns on the massive Cadillacs, they sound more like a train than a car. Some quick research revealed that some 1970s Cadillac Broughams were equipped with an optional "trumpet horn package" that included 4 giant horns as opposed to just the standard two horn arrangement. While at the junkyard I scoped out the biggest car I could find, thinking it would have all of the bells and whistles, so to speak. The car ended up being a 1970 Cadillac Fleetwood Brougham d'Elegance Royale Landau Signature Series, a name as long as the car.
Looked like this:
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...only rusty.
And in that house-sized engine bay I found the elusive trumpet horn set.
I will let you guess which belong to the Cadillac and which were OEM Toyota. Following a de-rustification and painting:
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These horns are enourmous, so I mounted two in the stock location behind the grill and two more adjacent to the battery. On Cadillacs, they are mounted in a similar location on either side of the car.
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You must use a relay with these, they pull an un-godly 22.2 amps.
Looking down from above:
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The trumpet horn package has one A note, one C, one D and one F note. They sound fabulous. It doesn't just sound loud, it sounds awesome.
I will leave you with a quick video/audio of them installed:
<iframe width="420" height="315" src="//www.youtube.com/embed/ljZWstarTsc" frameborder="0" allowfullscreen></iframe>
Thanks for keeping this thread updated. I was wondering about the relay used for the horns. My dad used to drive Caddys when I was growing up and I always got a kick out of the way these horns sounded.
My wife does crash injury potential work for a consulting firm and she tells me stories about car accidents where loose cargo is the cause for injuries and deaths as opposed to the actual car accident itself. Hearing these stories was enough to encourage me to do something about it. Now that we have our first newborn baby riding with us, addressing this issue was moved up the priority list.
I realized there were some very specific places I needed tie-down points to secure our camping gear. I usually place the ice chest and kitchen stuff (packed in an Action Packer) between the wheelwells, so I wanted to secure those with a strap across the center of both. Previously I used the four factory tie-down points in an X-pattern, but it was a pain getting to the rear cargo loops and everything in the cargo area was a different height and thus not very secure.
I discovered that Jeep Wranglers do not come from the factory with any cargo loops (surprise surprise) and the popular Jeep mod is to use 4Runner tie down loops. The 4Runner loops have friction in them and don't flop around and make noise like many of the other aftermarket cargo loops, so I bought eight more (!!) and started installing them where they were needed.
One added on each wheel well:
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Overall cargo area view:
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Inside the wheelwell I installed a small 2x3" 16 gauge steel backing plate between the body and the nut on the bottom. It's more reinforcing than the factory used and if you were in a really bad accident it would help prevent the nut and washer from pulling through the sheet metal.
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I have a few more going in on the floor of the backseat area to secure other heavy items like our water jug and daycooler.
Hopefully if the unthinkable happens, we will be a little more protected from our heavy cargo.
Lightbar wiring the hard way. I tried all of the easy ways, such as running the wires down the window channel, but those methods did not give me a clean install. Sometimes the best way to do things is to drill holes. Two of them, in this case.
I elected to use a single cable entry gland to get the lightbar wiring in to the cab.
![]()
Rather than drill three additional holes for mounting screws, I used 3M VHB (very high bond) tape to adhere the cable gland to the roof and also act as a gasket. That has worked great on my Sprinter van solar entry gland.
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Man, gotta love search engines. Came across this old post and had to give you props for drilling into the roof skin.
I'm in the infant stage on installing my SP9100, Duel Battery, and exterior accessories. Although ran through fiberglass, I know of a jeep owner who's installed a Seaview Cable Gland and completed the mod successfully with zero issues so far. I have some serious decisions to make before drilling into the outer skin but these cable glands put my mind at ease. Hey, if these "off grid" vans can have permanently mounted rooftop solar with these type of pass thrus then it's something to look into instead of wiring coming out of hatches..etc. Cheers, BRPNW4R
...So I added the Blue Sea circuit breaker and fuse block with enough space for a couple of threaded knobs so the aluminum plate could be removed from the factory fuse box if I ever needed to read the printing on the top. (There are nuts JB-welded to the underside of the cover.) I was concerned the screws could loosen on washboard, so I went in later and added a safety pin so the whole shooting match couldn't go anywhere.
Have fun!
This looks like a clean and simple way to mount the plate to the fuse box. Do you know where you found those threaded knobs?
Love the look.. I just replaced my tires with 265/70/r16 again because I like keeping it simple. Wanting to switch to 99 talls and hope the 70 looks alright and I won't wish I'd have investigated 75s. Anyway yours is minimal and functional.. good work
Woopsies, someone crossed a solid white into my lane taking out my stock front bumper.
Damage to the 4Runner is pretty slight: (the flare used to extend all the way down)
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The offending vehicle didn't fare quite as well:
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I got estimates for insurance reasons and the repair shops indicated the fully boxed frames in the 2nd gen and 3rd gen 4Runners are some of the strongest around, and there would be zero chance mine is bent or misaligned in any way. Either way, the bumper manufacturer requires doing a test fit before painting or powder coating so you can return it if there are any problems.
Torn-down, test-fit went as planned
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And did the flasher relay today to prepare for the LED turn signals so I don't get hyper-flash.
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With that done I want to find some brighter LED turn signal bulbs for my LED Eagle Eye taillights. Any recommendations?
Today I picked up the new bumper, fresh out of powder coating...
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Thinking I may as well do a full front end swap. 2002 color matched grill, and some sort of projector LED headlight upgrade. Probably DIY on the latter since I'm not about to wait 22 months. You know how it goes, one mod leads to 5 others...
Torn-down, test-fit went as planned
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Is that the original under cover-thing on your hood or is that some ingenious aftermarket solution? Mine is destroyed.