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Timing belt, water pump, idler pulley, tensioner and pulley, accessory belts, upper radiator hose and coolant replaced. I used the stickied t-belt write-up and had very little difficulites. The biggest hang-up was trying to get the rear bolt of the belt tensioner. I found 1/4" gear worked very well since it is smaller. I fished the 12mm socket on a swivel that I wrapped with electrical tape to limit it's wobble and a bunch of extensions gives access from below. Another hiccup was in threading the timing belt. Being in the cold and rain must have slowed my brain as I mixed up my left and the motor's left and could not for the life of me figure out why the cams would line up but the crank was 6 teeth off. Flipping the belt facing OUT made everything line up straight the first time thru. And yes, if you put the upper radiator hose on backwards, the fan will grind a hole in it. So either plan on buying a new upper hose, or mind which way it's facing.
Also to those that say "I have XXX,000 miles on my original timing belt"... yes your timing belt may be holding together. Mine had 120k miles and still looked decent:
But it isn't always just about the belt.
Here is a pile of red coolant scale from the weeping water pump that was totally hidden behind the covers and waiting to fail and strand me somewhere or cause exponentially more damage and cost.
random blinking green/amber 4wd indicator while driving (now constant blinking)
successfully shift into 4LO with LO range gearing in transfer case and e-locker engagement
Checks:
Vacuum from manifold thru check valve to both VSV
can manually shift A.D.D. by applying vacuum to both sides of actuator with mighty-vac
VSVs appear to be working, vacuum from brown one in 2wd and blue one in 4wd (This has changed, I get vacuum out of the blue VSV all the time now)
Front diff switch shows open and closed on meter when pushed in or out
I still need to check the switches on the transfer case to see if it isn't sensing that it shifted or should shift. I'm also going to replace the vacuum lines that go from the VSVs to the front actuator. When I put the gauge on them, I get vacuum from the 4wd line (in 2wd and 4wd mode) but no vacuum from the 2wd side. Plus vacuum line is cheap and these runs are 16 years old.
I'm happy that I can switch the front axle manually.That can get me out of trouble if I ever get stuck in bad weather unprepared. I'm happy that the transfer case is shifting, that actuator is like $1k and used xfer cases are like $600+. If it ends up being a sensor, they are like $30 each and there should be 5 total. I don't know how much a 4wd module costs, that's the current only unknown.
On my 96 one of the metal vacuum lines that sit atop the front dif has a leak so that particular line has been bypassed completely by running the rubber tube all the way from point a to point b. Just saying don't discount that part of the vacuum because they're metal.
I ran 2 new legs of vacuum hose to each side of the front diff actuator. I had it in the shop and wanted to eliminate that steel lines from the equation.
I removed the 2 switches on the transfer case actuator and tested their continuity. The rear most had spots throughout the throw of the plunger where it would loose continuity. I cleaned it thoroughly with contact cleaner and worked its range until it had spot consistent signal. The front sensor closed circuit quickly and smoothly, but I cleaned it as well since I removed it.
No improvement and constant 4wd blink
I verified that shifting the j-shifter to 4HI locked the front driveshaft.
I checked vacuum out of the 2 VSVs. Regardless of shifter or M/M switch position, I have vacuum from the blue VSV and not the brown VSV.
Removed, cleaned, and verified function of the switch on the front diff. Also verified the actuator shaft in the front diff is moving by cycling the actuator with my Miti-Vac and checking if the shaft moved at the bottom of the switch hole. It does.
I also unplugged the front switch and the 2 switches on the transfer case actuator one at a time to see if the blinking light would stop.
So far the only variables I have left are the 2 top switches and the 4wd ECU itself.
So what has been the bane of my existence for the better part of 2 years has finally come down to a bad contact.
I followed the FSM flow charts, I took switch/sensors out and cleaned them, checked them, metered them. I replaced the vacuum lines to the front diff. I checked VSVs. I checked pins at the 4wd ECU in 2wd, M/M, 4HI, 4LO, rear diff lock and unlocked. I compared voltage and continuity to the EWD. I subscribed and downloaded a new EWD in case the '01 one was different. I hooked up the relay and a battery to the Transfer case actuator.
Everything pointed to my needing a new actuator at the cool bargain of $1000. When power was directly applied to the actuator it didn't move or make noise. The 4wd lights would blink on the dash and no matter what position the shifter was in, the transfer case and the computer were not jiving. Thinking I had nothing to lose, and having already shopped a used 135k mile trans case on eBay, I figured I would take the cover off the motor and take a look. Sadly I didn't take a picture. It was caked in dried yellow brown grease. No doubt original and 17 years old. The copper contact tabs were tarnished green with corrosion. I scrapped away all the old grease, sprayed everything with contact cleaner, and shined up the contacts with emery cloth. Re-assembled everything. Fired it up and shifted, Kah-clunk, lights blink and the go solid. I backed out of the driveway and could hear and feel the front end push around being engaged.
Here are some pics to help explain. Here is the inside of a new and clean actuator It is packed full of the yellow grease seen here on the motor drive wheel. These 3 contact pins ride along contact tracks in the cap which determine limit for shifting 2wd -> 4wd. These tabs were coated in a green tarnish. This is the cap with the contact traces. There was a dried and caked yellow grease and green tarnish on the contacts
There are a lot of people I want to thank for posts and comments along the way to my repair.
@99SC4Runner for starting the original 4wd blinking thread 10 years ago
@TheDurk for uploading EWDs and explaining a lot of the pin functions
@Rock Slide for pictures of the switch locations and explaining that you can disassemble the motor cover
@Kolton5543 for quickly pointing me to components
@aowRS for offering parts
@Habenero for following
@FunRunnerGal for youtube videos
and basically anyone and everyone that contributed to the thread. Everybody's information, experience, pictures, diagrams, etc. is what makes repairs like these tolerable.
Flushed power steering system with new Dex 3 trans fluid and installed Wix 58964 magna-filter in the return line. Now that I've rounded the corner and repaired everything that I know was wrong with the truck or was a known issue with 3rd gens, I'm taking steps towards long term maintenance and preventative acts. Next up will be a trans flush and magna filter install in the cooler loop.
Here is the filter on the return line from the rack to the reservoir
Last edited by fierohink; 11-28-2017 at 10:43 AM.
Reason: added a picture
I bought a 5 gallon bucket of Dex 3 ATF last winter in hopes of changing/flushing my transmission. I don't think the previous owner every did since it wasn't listed in any of the maintenance logs I got when I bought the truck.
Here is my crash course write-up on DIY transmission flushing: Dirty Smear of fluid to begin. At every fuel fill-up I would check my fluids and this never had a burnt smell, but has been slowly getting darker. I drained the pan first. This was a lot worse than I thought. It's basically black. Fresh ATF The final purge. This is the final purge of fluid. Still a little dark, but it is nearly red when poured against something. Clean Smear of fluid after the flush
Summary of flush:
Drain the fluid from the transmission pan and measure it for quantity.
Refill with fresh DEX 3 ATF the amount you drained from the pan.
Disconnect the cooler line that runs from the transmission to the radiator (or in my case external cooler, you do not want to milkshake your trans)
Direct the cooler line into a container.
I used a gallon milk jug that I marked in 1/2 QT increments
Start truck and cycle through the gears for about 20-30 seconds.
Check you jug and measure how much fluid came out and refill your trans with that amount of fresh ATF
Repeat starting the truck for 20-30 seconds -> refilling trans until you have either clean red fluid coming out (or in my case, you run out of ATF)
Oil change with 5.5 qts Valvoline High Mileage and toyota y3 filter.
Tire rotation which has caused some problems that I put on the tire shop that installed my tires. I purchased 5 tires with the intent of maintaining a 5 wheel rotation. When I bought the truck I glanced underneath to verify that I had a regular rim instead of a steel wheel spare. I never gave it much more thought than that. My spare, as it turns out, is a split 3 rim. This doesn't match the solid 5 rim of the other 4, which as it turns out doesn't fit over the Tundra Brake upgraded calipers.
Spare rim Other 4 rims and an extra I had in the garage
I say I blame the tire shop, is they didn't mention that my spare rim was different than the other 4 and I had a matching spare rim in my garage which could have been swapped in and the resulting problems made moot.
While I was trying to rotate my tires, I was also trying to install the dynamic wheel balancing beads into each tire. Wheel balancing can be either static or dynamic, static being the conventional weights that hook onto the inner and outer rim edge, or affixed to the inner dish, dynamic is a loose bead (plastic, ceramic, metal, etc) that is added to the air space inside the tire/wheel assembly that can move around thru the centrifugal forces at play naturally offsetting imbalance. With bigger off-road or truck tires, the manufacturing process can lead to irregularities and significant balance issues. Some to the point where you just can't add enough weight to a rim to correct.
OTR trucks use dynamic balancing a lot. Most use a disc that bolts between the hub and the wheel with metal shot that can spin around a track (think hula-hoop) and help to balance.
I went with E-Z Tire Beads and 6 ounces of ceramic beads per wheel. I also replaced the valve cores with the filter style to allow air pressure maintenance. And here is my little write-up:
Included Valve core removal tool. Dynamic ceramic beads and filler bottle Remove original valve core Standard valve core on left, filter core on right Filling the bottle with beads, 6 ounces do NOT fit in the bottle at once Slowly adding beads to tire with included bottle and tube. Beads clogging the tube
The good and the bad. The good, the dynamic tire weight improves vibrations from 10-55mph, over 60 the shimmies and shakes start to come back and are noticeable above 75. Maybe I shouldn't cruise and commute at 75-80?
The bad, the wife took the 4runner to the store because we've gotten a bit of snow. She called me after 15 minutes or so of driving about something unrelated and asked me "how long has your check engine light been on?", to which I replied, it isn't... when did it come on and what did you do?
So I scanned the truck when she got home and I have a p0304 and p0300 miss. I've had misses with a blinking CEL before and turned out to be some injectors that died. I still have 2 spares from that ordeal and will swap #4 out tomorrow at work and see how things go.
Swapped the ignition wire from 1-4 with the 5-2 wire. CEL miss moved to P0302 for a #2 cylinder miss. NAPA replaced/warrantied my wires. I changed them out in the parking lot and so far on the ride home had a significant improvement in performance. It still has a slightly hesitation, but I'm attributing that to clearly out the CEL codes and not having driven enough for the computer to fill out it's parameter tables.
11-08-2017, 12:43 PM
